 Welcome to another seminar series from the Blue Mountain Natural Resources Institute. I'm the Institute Manager, Larry Hartman. The Blue Mountains Natural Resources Institute is a part of the Pacific Northwest Station of Forest Service Research and is also funded by the Pacific Northwest Region of the National Forest System. Our territory includes all of the Blue Mountains, including 10 counties in Oregon and four counties in Washington. The Institute achieves its success by working with its partners, which include federal, state, tribal, and local government agencies, as well as industry, environmental organizations, private landowners, and educational institutions. The Institute does three main types of activities. First, we offer educational activities and technology transfer, including seminars like this one. Second, we do research management tours, publications, videos, and we even sponsor conferences. Second, we conduct applied research, which is designed to meet real-world resource management problems. Third, the Institute serves as a neutral forum for discussing environmental issues so that people or organizations with differing opinions can get to understand one another better. This presentation exemplifies the Institute's goal of putting science to work. It's part of our ongoing commitment to bring science results to resource managers and to the general public. This seminar series is entitled Cottonwood and Aspen, Managing for Balance, Ecology, and Management, which examines the importance of cottonwood and aspen as components of ecosystem diversity. The second of the three sessions examines two subjects. Cottonwood and Aspen is wildlife habitat, a focus on birds, and silviculture and management of aspen in the west. I hope you find it interesting. We'll get started. Our first speaker this evening is Josh Tuxbury, and Josh is a graduate student with the Montana Cooperative Wildlife Research Unit in Montana. He's in the Intermountain Research Station in Missoula, and Josh has a Bachelor of Arts degree from Prescott College in field biology, currently a student in organismal biology and ecology, and that's a heck of a mouthful. I don't know. I don't think I'd put that on a business card, Josh. Josh's research background has been on butterfly distribution in central Arizona. He's also worked on breeding bird productivity in cottonwood and aspen habitats in western Montana, and he's also worked on nurse plant ecology in the Sonoran Desert and in the Midrian Mountains. These are places I've never been, so I really don't know how to pronounce those. But this evening Josh will address the cottonwood and aspen as wildlife habitat, diversity, importance, and impacts. Let's welcome Josh Tuxbury. Thank you, Bill. I appreciate it. Okay. Well, I've got a focus today on the latter part of the research there. I'm actually currently still doing the work on breeding bird biology in cottonwood and aspen, and I'll use some of that data from the first year of work we've done there in this presentation. Deciduous riparian communities in the western United States dominated by aspen and cottonwood support some of the most diverse and abundant wildlife throughout in the western United States. From reptiles and amphibians spending most of their life cycle in these communities up through dominant herbivores such as elk grazing or browsing on a lot of the lush vegetation and in winter using the aspen themselves, eating the inner cambium of the bark, we find that these communities are truly the aorta of an ecosystem. They're really where wildlife is most abundant, especially in the west. This is particularly true for birds, like cedar waxlings here. A large number of bird species spend most of their time and particularly breeding in riparian habitats. And if you're walking through an aspen grove in the western United States in the summer, you might see an American red start up in the canopy or flitting around in the understory bushes. Red starts and over 50% of the other birds we see in riparian areas are what are called neotropical migrants. These birds spend most of their time on their wintering grounds down in here and in the west, that's in western Mexico and Central America, and then move up to the breeding grounds for breeding. Notice for most of these species, the breeding range is quite a bit larger than the wintering range. And this may reflect greater and more specific resource needs on the breeding grounds where they have to set up shop and raise a family, as it were. So, I actually didn't pan it out. In fact, what we find is that most of these birds have very strong habitat affinities. And a large number of them choose to breed in riparian areas. Fully 60% of the birds that breed in the western United States or the bird species that breed in the western United States breed primarily in riparian habitats. And this is really amazing when you consider that riparian habitats make up less than 1% of western land area. So clearly this is a critical resource for breeding birds. Additionally, these riparian habitats are some of the most impacted zones in the western United States. And as an example, some western states have proposed that less than 5% of the historical riparian vegetation still exists today, and Arizona has, for instance, stated that. So it may be caused for alarm here, given that we have a habitat type that's so rare, so critical, and has undergone some considerable impact in the last 200 years. What I'd like to talk about today is two general topics, is basically the importance of these riparian habitats to wildlife, and in particular to birds, and then move to the threats we see to the quality of these habitats. I'll start with the importance here. Why are these habitats so important to birds? What is it that makes so many birds congregate in these areas? And the first thing is productivity. These habitats are far and away more productive than any of the other non-riperian areas we see in the western United States, and this goes for both Aspen and Cottonwood along river valleys. And if we look in terms of plant diversity and plant abundance, a large amount of plant species are in these areas. And to understand this productivity, it's useful to look at the interface between aquatic and terrestrial environments. Plant areas define that interface in the western United States, and we see abundant nutrient exchanges going on right here at the interface between these two habitats. Additionally, well, this then in turn creates the environment for lush vegetation to grow, plenty of available soil moisture, and we get the communities we see there complex vegetation, and with the complex vegetation come many, many bird species. The reason for all these birds congregating in this area, there's two primary causes. One is the insect abundance that we find here. Moist environments, open water, complex vegetation provide excellent habitat for an abundance of insects, and this is the primary food of most of the birds that we see in these habitats. Additionally, birds specialize on nest sites. Not every bird puts its nest in the same place, and that's evident when we look at anything from Robbins to Woodpeckers. So in a complex environment like a riparian area, there are many more opportunities for differing nest placements, so more birds can congregate in one area, especially when we can compare this to upland vegetation, which is structurally much more simple. There's only a relatively few number of places where you could place a nest and avoid a predator, whereas in the previous slide, there's many, many places. The second thing we want to think about when looking at the riparian habitats and all the birds they have is that not all birds are in one riparian habitat. In fact, habitat diversity is a key to why we see such abundance of birds in these areas, and from just a structural standpoint, cottonwood and aspen habitats focusing on here are quite different, and cottonwood and aspen habitats normally have a single layer canopy and relatively thick understory bushes underneath them, whereas cottonwood areas often are multi-storied with tall shrubs underneath the cottonwood canopy and providing different resources than the aspen areas. So birds oftentimes will specialize on a certain type of habitat there, taking resources from one and not another, and therefore the total diversity of birds we see in riparian areas is actually made up of very diverse pockets that are quite different from each other in aspen and in cottonwood. Furthering this difference is the topographic location of topographic differences between cottonwood and aspen. Where I'm working in western Montana, aspen occurs on these slopes up in here, and cottonwood is along the large river valley in the bottom. There's only about 400 feet difference in elevation, usually quite a bit less, yet even with this small elevation difference we see consistent temperature differences throughout the day in these areas, and especially in the daytime and you can see in this slide cottonwood habitats are substantially warmer than aspen habitats. This is temperature here in just the hours of the day on the bottom axis here. At night these habitats are also, they look quite similar here, but when we account for structural differences and take measurements at nest sites, we find that nests in aspen up in only slightly higher environments are cooler. And this might be, this might further the difference in bird communities and influence the success of birds in these different areas, simply because nestlings and eggs are very sensitive to excess cold and heat. And we see differences in between species and their ability to cope with heat stress and with excess cold. So these two things combined, looking at may both influence bird diversity and differences in bird communities between these habitats. And in the first year of data that I collected, and I realize that these are probably quite a bit too small to see, we found considerable specialization in bird communities, such that the species up in here, and I'll read some of the names here, this is like song sparrows, spotted sandpipers, western wood pewees, house wrens, blackbirds, nests almost exclusively the black here is cottonwood habitat, with only a very few number of nests if any found in the aspen area here. Conversely, things like solitary verios, chipping sparrows, dark-eyed juncos, dusky flycatchers, American redstarts, McGillivry's warblers are found almost exclusively in the aspen zone. And the other thing I want to point out about these habitats is just the sheer diversity in bird numbers that one year of searching for nests can come up with. We monitored nests for 71 different species of birds in these habitats. It's unlikely that any upland habitat supports near that number of birds. So the importance of habitat is pretty clear to bird communities, and the different types of habitat are important to different birds. Species make individual decisions and responses to different habitat variables. At this point I want to talk a little bit about the habitat quality, what allows these birds to successfully breed in these habitats, and threats to that quality. The first one I want to speak on is fragmentation. Research on fragmentation and bird response to fragmentation has been done almost entirely in the eastern United States, where deciduous forests have been fragmented, and you get a lot of negative effects on bird communities. The difference here with these western riparian systems, cottonwood gallery forests, aspen communities, is they're naturally fragmented ecosystems. You see here they make linear strips along river valleys, and cottonwoods are found in small pockets, snow pockets, along small streams. So these naturally fragmented ecosystems may not respond to fragmentation in the same way. And at first we may expect them to have a less of an effect to continued fragmentation. But in fact, the larger stands consistently support more species, and this is true for both aspen and cottonwood. Because they're naturally fragmented to begin with, but because of the area requirements of some species and resource requirements of others, we see consistently larger stands supporting more species, and drainages in the case of aspen that are larger, larger drainages having more species. So both at a landscape level and at a stand level, area has an important effect on bird diversity found in these stands. Additionally, natural disturbance has played a key role in rejuvenation of these communities, both in cottonwood and in aspen. And there's much less natural disturbance happening in these habitats than historically prevailed. For cottonwood, flooding seems to be the primary mode of regeneration of cottonwood seedlings. Rejuvenation of sandbars allows regeneration of small cottonwoods much like plowing your field allows you to then plant a crop. So without this flooding, there's reduced regeneration in cottonwood stands, and the stands become much more simplistic, and you don't get a lot of the small cottonwoods. Aspen on the other hand is not concerned so much with floods, but it does have but natural disturbance in the form of fires seems to play a key role, especially in the serral aspen stands or in western Montana that I work with. With where I'm working, we're seeing a continual decline in the abundance of aspen on the landscape. And the process that is causing this seems to be an increase in conifer species moving up through these serral aspen stands, shading them out, and then causing basically the community changes into a coniferous riparian area. Conifer riparian is a very beautiful habitat, but it doesn't support near the number of birds or other wildlife species as the deciduous areas. Additionally because deciduous areas are so rare to begin with, their value can't be overemphasized. So we've talked about fragmentation, lack of natural disturbance as both potential threats to the quality of wildlife habitat of aspen and cottonwood forests. Grasing in the western United States has had numerous effects on riparian areas. And the damage that grazing can do comes in four basic forms, soil, soil compaction and there we go, I'll just zoom in on this first part, soil compaction, foliage removal, physical damage to vegetation here, and elimination of riparian habitat outright through channel widening, erosion, and lowering of the water table. However, the impacts of grazing depend a lot on the intensity of grazing and the season. And it's been pretty clear that summer grazing, and intense summer grazing especially, is much more detrimental to bird species than is late fall grazing, and perhaps even early spring grazing before the growing season has gone underway. And a recent review of work that's been done on birds in grazed and ungrazed habitats found that almost half the birds in these habitats show significant declines with grazing. And whereas 30% increase with grazing, so there's a very, again, species specific changes between each species' response individually to grazing. The nature of the species that decline is quite a bit different from those that increase with grazing, and as we would expect, species dependent on lower vegetation levels are decreased with grazing, and oftentimes these are specialist species, species that either specialize just on a certain vegetation level, and more importantly, often specialize on riparian habitats and aren't found in other areas. In contrast, species that increase with grazing tend to be more generalist in nature. They're aerial foragers that like open habitat like bluebirds, and they're also open area associates. Robins do just fine with grazing, and so we see a general change in the bird community associated with these grazed habitats. Visually, the difference in grazed and ungrazed habitats is pretty clear. This is an ungrazed site along the Snake River, and they can see that vegetation extends right to the water, and there's a complex multi-story canopy in these habitats. Contrasting that with a moderately grazed site, you can see that there's very little vegetation density around the base of the trees, where a lot of your lower nesting and ground foraging species would normally be. It's also, it looks a lot drier, and that's maybe because of soil compaction, and so the differences between grazed and ungrazed sites are pretty extreme. The last issue I want to focus on here is the surrounding landscape use. We know that these three issues here are all three on-site effects, as I call them. There are things that happen directly to a landscape, grazing on the landscape, fragmentation of a certain habitat patch, or disturbance affects the area where the disturbance happens. However, the use of surrounding landscapes may also play a role in determining bird abundance and the health of bird communities in riparian systems. This is where I focused my research recently, and it seems to be a little more less cut and dry than grazing and other issues that have been studied quite a bit more. Cottonwood Valley bottom forests are typically surrounded by a matrix of agriculture and urban development. Out here, it's a lot more range land than where I work in less cloud fields, but this is normally because these large river valleys have some of the best soils available in the West, so we see a lot of encroachment on these systems. In contrast, this is an aspen stand, one of my study sites I'm working in, surrounded by coniferous forest. This is typical where I work as the aspen is largely in the conifer forest, and aspen is largely in the conifer forest, and somewhat buffered from the effects of agriculture or some of the buffered from the agriculture by this forest. Taking a more explicit view, this is just a vegetation coverage map of a lowland cottonwood site that I was looking at birds on, and the orange is the agriculture around this site. Red represents more deciduous cottonwood-dominated habitat, and the greens are forest. This is a range land out in this area on the east here. It's real obvious right away that agriculture makes up close to 40% of this area directly surrounding the site, and this is in dramatic contrast to the aspen sites that I'm working on, which are surrounded mostly in green by forest lands, and the red here is other aspen stands. It's important also to note that I still see quite a bit of agriculture creeping up not too far from this. The question I'm really asking is, what affected these dramatically differing landscapes from here and here have on the bird communities that are breeding in these sites right here in the cottonwood and the aspen sites on the landscape, and specifically on the health of the birds breeding there? How successful are they when they breed? The first process I want to discuss regarding that is changes in predator communities. We may expect predators associated with the forested habitats to be different than those associated with areas surrounded by agriculture and urbanization. Things like fox, coyote, squirrel, all three are efficient nest predators, and when I'm talking about predation, I'm specifically talking about predation on bird nests, and so those are very effective nest predators, and they may be more abundant in a forested landscape slightly removed from agriculture. But in contrast, things like ravens and crows, and especially magpies, as well as house cats, raccoons, are typically associated with agricultural landscapes, and magpies are especially good nest predators, and they're also highly correlated with the presence of agriculture because they feed on everything from dog food to field insects and nest primarily along the edges of riparian areas. So when looking at these things we see, when looking at the effects of these different predator communities, what I'm showing here is simply the top graph is the number of nests we found in the different habitats. The black bars represent cottonwood, excuse me, the white bars are aspen habitats, and again the aspen habitats are surrounded by coniferous forest, and these are much more surrounded by agriculture. The top graph represents the number of nests found, and the bottom graph is a measure of success of these species here in the different habitats. The first thing, the first generalization that is important to look at is that high nesting density, where you see the most birds, doesn't necessarily mean that's where they're the most successful. We see this situation in both the yellow warbler that nests almost exclusively in cottonwood groves, yet does a little bit better in the aspen when it nests there. We also see it in the warbling vario that nests slightly more often in the aspen, but does over twice as well as far as nesting success in the cottonwood. Additionally, I want to point out a couple of species that these species only nest in aspen zones, the American Red Star and the Swainsons Thrush, but their nesting success is quite low there. So predation invokes an individual response. Different predators are better at finding the nest of certain species, and we see, therefore we see each species responding differently to changes in predator communities. Now we're going to continue to study that over the next couple of years to try and get a better handle on how these different species are reacting. Another process that might help explain differences in success of these species comes through when you have agriculture, you often have cows, and with cows we get cowbirds. So nest parasites, they have developed an interesting evolutionary strategy. They seem to have decided that it's a lot of work to build a nest and it's a lot of work to raise young. So instead they opt to lay their eggs in the nest of other bird species. And this works out great for the cowbirds because the other species take the egg on as their own and raise it to completion. But it's often at the detriment of their own young. This is a cowbird egg and this is actually a bunting egg in here, indigo bunting. And what happens is the cowbird egg hatches much more quickly and the cowbird young grows much faster and is much more aggressive than the young of say yellow warbler, a bunting or whatever else species that is parasitized. Therefore it starves out the other nestlings and it's kind of a sad sight to see a yellow warbler feeding a cowbird three times its size near the end of the nesting period. But where you have abundant cowbirds, that's often the case. And in some areas where cowbirds are particularly abundant, we've seen local extinctions of species. For instance, there's no buntings down in my sites anymore and they used to be quite common there, down in the cottonwood areas. Historically, it's definitely a part of their range. What about parasitism then in the different sites? In valley bottom cottonwood areas around agriculture and in foothill aspen zones surrounded by coniferous forest, we see in some species that there's definitely a difference in predation rates between these areas. Yellow warblers do quite a bit, get parasitized much more often in the cottonwood than they do in the aspen when they're removed from agriculture. And this may explain some of the differences with this species in success versus where they want to nest. We saw before that they almost always nest in the cottonwood. Perhaps that was the best site for yellow warblers, but with the introduction of cowbirds that the success of the nest has declined and now they're actually doing better in the aspen because there's less parasitism. However, it doesn't explain what's going on with the warbling vario because high parasitism in both areas. What this points to and what the general occurrence of parasitism in the aspen points to is that you may need to be further away from agriculture to get away from parasitism. Now if we just look at both these study sites that I was just pointing out before on one landscape, this is the one in the valley bottoms. Again, this is agriculture here in orange and the green is coniferous forest and this is the foothills site dominated by aspen up here. Notice you're only a couple kilometers from the agriculture. Cowbirds feed almost exclusively in feedlots, in fields, around cows, they grew up with bison. That's their general habitat or they evolved with bison. So they have moved in with the increase in agriculture in the western United States and they need this kind of habitat for feeding grounds. But we're finding that they don't have much of a problem flying two or three kilometers to find good areas to lay their eggs. This is a troubling finding given that it's pretty hard to further isolate stands of aspen once agriculture is close. So in general, in wrapping up the landscape section, it seems to be quite a complex issue where predation and parasitism affect different birds in different ways and there's no sort of blanket management decision we can make to reduce parasitism and predation on all species at all. I want to kind of bring this around the end here to talk about some basic management recommendations that stem from the threats or impacts on riparian areas, that some of which are applicable to landowners of these areas and others of which will require cooperative work between agencies and dip between landowners. As far as addressing fragmentation, a pretty simple recipe is to try and preserve stands of the largest size possible. And at least a couple of studies in Cottonwood, they found that stands of seven hectares or greater support pretty much the entire complement of birds that would be found there. You don't get a lot more species when you get above seven hectares as far as the size of a stand. You do lose species when you get below that. When we look at disturbance, the remedies may be different for aspen than they are for Cottonwood and I think that the disturbance in aspen will be addressed somewhat more by other speakers. But indeed, in aspen it may require some thinning of conifers that are growing up through these sterile stands or in some cases managed fire has been used pretty effectively where I've worked in keeping the aspen on the landscape where normally it is disappearing. It's hard to manage floods and that's really what Cottonwood needs. Rivers are usually controlled by dams and most of our rivers are dam pretty heavily. So from a landowner perspective, it's hard to do much about flooding regimes. However, a couple of things we can do and the first seems a little counterintuitive and I say manage for beavers. Beavers ring Cottonwood trees and so first thought would be that they would be detrimental to the health of these systems. But recent evidence and some really interesting research has shown that when Cottonwood trees are ringed, they put out a whole bunch of nice little sprouts, they're suckers that come off the bottom of the Cottonwood trees and we see that on our sites. And some work has shown that it actually can increase the lifespan of a tree by suckering like this after a beaver kill and it definitely increases the heterogeneity of the landscape or of the Cottonwood Grove because you get these small clumps growing up underneath tall Cottonwoods and without regular regeneration, those form the shrub layer in some areas. So beavers, the basic take home message with beavers is they're not all bad for Cottonwoods. It's pretty new as far as how good they are but it's definitely food for thought. Managing for flooding, as I said, would be difficult but one thing we can do is trying to discourage building on the floodplain because we can't get floods on a floodplain if people's houses are there, the loss of personal property and such. So decreasing building on the floodplain can help us then go ahead and introduce or we'll be able to sustain higher water levels and help regenerate Cottonwood. And this also will allow for sandbar creation, let me zoom this in a bit. Talk about grazing here. Grazing is something that we can do a lot of management to really help out the interaction between grazing and wildlife. The first thing is whenever possible just to exclude cows from riparian areas. That's not always possible but it's certainly the most straightforward way of minimizing grazing impacts. When cows need to use riparian areas for water and for forage, eliminating the summer grazing may be most crucial and what this requires really is just managing your riparian areas separately from your surrounding upland areas and incorporating late fall and early spring grazing in riparian areas but trying to keep cattle out of these areas during the most critical growing periods for the riparian zones. Additionally, we can use things like restrictive access fencing and alternative water sources to help keep cattle out of these areas in high densities. In many cases what we need is riparian recovery and some regeneration, rehabilitation of these habitats through complete rest from grazing until we can manage both for grazing and for wildlife diversity. And there's certainly a case to be made that those aren't mutually exclusive. It will require a lot of work and cooperation among both conservationists and biologists and landowners and to try and pull those two activities together. Surrounding land use is pretty hard to move your farm or move someone else's farm but there's certain things we can do to reduce the number of cow birds on the landscape and potentially reduce the abundance of predators around agriculture. One thing we can do is just try to keep feedlots at a distance from riparian areas. There's definitely been shown that cow birds will parasitize more nests closer to where they feed and there's a decreasing function of parasitism as they get further from the feeding areas. Additionally, buffers around riparian systems in terms of forests will help some species. It won't be a cure-all but it will help some species as far as parasitism is concerned. The other issue really is reducing predator trash and that's when I say predator trash, I'm speaking of the things that like your dog food and other things that you can leave out that left out increased predator abundance by providing them virtually unlimited food sources. This is for things like magpies, raccoons, crows, ravens and just reducing that will help reduce predator communities and reduce predation rates. So in closing, I've kind of given a broad brush of some of the important aspects of cotton wood and aspen riparian zones to wildlife and talked about some of the threats to these zones, grazing, surrounding land uses, fragmentation and lack of natural disturbance and then some basic management recommendations for how we can better manage these areas in the future, see the same diversity of wildlife in these areas that we enjoy there today. That's all I have. Thank you. We have questions from the audience. Let's take some from our local site here first and then we can go to the remote sites and see what we have. Any questions for Josh? Boy, Josh, you didn't really answer all the questions. I couldn't have. I mean, I just barely skimmed on a lot of them. Someone's got to have a question. Sure. Did you look at cavity nesters as well? I know you have to push down your button. Did you do it once? I'm sorry. Quick wishing my button fell. Okay. Yeah, we did look at cavity nesters. What we do is we monitor nests for all the birds on the sites and so cavity nesters, we do see quite a bit of difference in the cavity nester communities between cotton wood and aspen sites because aspen provides excellent areas for a lot of your woodpeckers. They seem to bore preferentially in aspen trees and they have, species definitely prefer different, they're choosing the softest trees to find and to bore their holes into. So there's definitely differences in the woodpecker communities and then secondary cavity nesters such as chickadees that use those holes afterwards. So we did look at those, yeah. Yeah. I had a question. Josh, did you notice in your censicing of songbirds in aspen and conifer, where was the highest number of species? Was it in pure aspen or in mixed stands? I asked this question because that's what a couple of researchers in Colorado found a number of years ago. Yeah. They found that the highest diversity was in the mixed stands as I recall. And I have not sensed a gradient of coniferous mixed and then pure aspen. So I can't address that directly, although we have done censuses in the conifers and in the aspen and there's a much greater diversity of birds in the aspen. But looking at the interface between those, I can't address that very well. I'm not sure. Some of our sites have quite a bit of coniferous in them and through next year's data we should be able to address that. That's a good question, though. More questions from LeGrand? How about our remote sites? Do we have our audio bridges up? Yeah, go ahead, John. Yeah, I have a question about have we got any experience with artificially creating flood conditions for regeneration of cottonwood, perhaps using different kinds of site prep methods to create that seed bed that's similar? I'm not sure if we have too much direct experience with it, although there's been lots of work done recently on regenerating cottonwood habitats through planting of seedlings, lots of work in the southwest that I know of and there may be quite a bit up here as well. I don't know about creating flood conditions. I do know that a lot of work has also been done on decreasing the rate of water flow through these areas because when you have high water flow you end up getting a lot of erosion and it takes away the sandbars that are crucial for cottonwood establishment so when we put up barriers to water flow we can recreate sandbars and then in that way help with cottonwood establishment. That would also raise the water table, too, in doing that. Indeed. Raises the water table, definitely. Any other questions from remote sites? Go ahead. Yeah. And if so, what species did you notice that they... The prenation by these squirrels? Is that the question? Yep. By squirrels or flying squirrels? We have flying squirrels and red squirrels, tree squirrels in our habitat as well as quite a bit of chipmunks. I don't know the effect of flying squirrels. They're pretty rare where we are. But they do exist there. The squirrel predation, it's difficult to observe a squirrel preying on nests, but we did actually end up seeing quite a bit of that this year. And they're throughout the landscape and we're doing some work to see if predation rates are higher closer to squirrel middens and areas where they pull apart the pine cones and stuff like that for feeding to see if predation rates are higher in that area than further away from squirrel activity zones. So we're mapping squirrel abundance and their distributions and then trying to correlate that with predation rates. And so don't have the answer to it for that yet, but hopefully later on this year we'll have some information on that. Okay. Other questions from remote sites? Go ahead. It's a really good question and there's not been a lot of research to really pin down what aspects of cattle grazing and agriculture cowbirds are keyed on most. Cowbirds expanded into the west typically by following some of the pack stations that were created along the Pacific coast and then up into the inland northwest later on. You can actually, if they're not actually correlated with simply clearing of landscape as they are with pack stations, actual introduction of cattle and open field agriculture where you have abundance of insects in the plowed fields. So there needs to be a lot more work done in figuring out what aspects they're directly keying on. I've seen them a lot around cows and the reason they're around cows is they're a lot like bison. They kick up insects and then the cowbirds can grab the insects when they fly up from the ground. So I don't think they'd follow cows into habitats that didn't have a lot of insects for them to eat. That's just a thought on that. Okay. Thank you. Yeah. More questions? Any from LaGrande? Great. Boy, I don't know. Quite audience. I think there's got to be a lot more issues out there. I'm sure there are. But thanks for everyone for that. John, Nate. Go ahead. Yes, could you elaborate again on the summer period in grazing? I'm curious about the relationship of what's going on in the detrimental and also how that might pertain to big game. Excellent question. Yeah. The studies that have been done on grazing in riparian areas, there's been about nine studies that have really good sort of graved and non-grazed type treatments. And what those studies have found is that the summer graze, when they compare summer grazing and non-graze, they find dramatic differences in both bird community structure and also success of a lot of these species. So that when you have intense summer grazing, it definitely seems to affect bird communities a lot more than in late fall grazing. The reasons proposed for this are basically because cows don't eat birds or anything like that. They trample vegetation. And from a bird standpoint, once they finish nesting, they don't need that vegetation as much anymore, because most of them go down south for the winter. And if it's late enough in the season, vegetation has time enough to rebound next year to provide appropriate nesting habitat for those birds. As far as from a big game aspect, I don't know the specific relationships between a big game use of riparian areas and grazing, although I could easily see them competing for some of that forage. So I have to defer a direct answer to that question to someone who knows more about the big game relationships in that habitat. But thank you. It's a good question, though. The second speaker we have this evening is Dr. Wayne Shepherd. Wayne is a research civil cultureist at the Rocky Mountain Forest and Range Experiment Station in Fort Collins, Colorado. He holds a bachelor's degree in outdoor recreation and master's and PhD degrees in civil culture from Colorado State University. Wayne is a native of Colorado. He's been with the Forest Service since 1969. His research career is concentrated on the regeneration of sobalpine fir and montane conifers, as well as the growth, development, and civil culture of Aspen. He is currently investigating alternate civil cultural strategies to manage Aspen forests in the southern Rockies and southwest. Tonight he will address civil culture and management of Aspen in the west. Please help me welcome Dr. Wayne Shepherd. Thanks, Bill. Well, I think this talk is going to be pretty much the Cliff's Notes version of Aspen management in the west. And as I drove around here in the Blue Mountains this afternoon, I realized that a lot of what you're going to see is probably a little different than what Aspen is like in eastern Oregon. But nevertheless, I think that there's something to be learned from this because now we're going to switch gears a little bit and talk about Aspen the Beast, how it behaves, its silvic characteristics, what are some techniques that we figured out over the years to regenerate it. So I think to get started, I would like to reiterate something I think that you probably heard last week and that is that Aspen is probably one of the most widely distributed tree species in North America. It literally goes from Alaska to Canada from all the way down into Mexico. There are a few known Aspen sites in Mexico. But one point that I would like to make is that even though we're talking about the same species, populist tremuloides, Aspen in the eastern part of the United States grows and behaves ecologically a lot different than it does in the western part of its range. And the reason for that is really the climate. Aspen in the west for one thing lives a lot longer than Aspen does in the east and that's primarily climate driven. If we look at the acreages of Aspen that are growing in western states and you'll notice that Oregon and Washington are not on here and I apologize for that but the data sources that I got this from did not have any data on those two states. You can see that by far and large most of the Aspen are in Colorado and Utah. And there's less Aspen in some of the other states. That reflects the development of stand conditions as we'll see in a minute as far as whether we're talking about stable Aspen or whether we're talking about Aspen that is really sterile or short-lived on the landscape. Again the red is non-commercial here. The split between commercial and non-commercial acreages is probably a little misleading from this data because technology has caught up with this since this data came out. A lot of the Aspen stands that were classified as non-commercial here are in fact probably commercial today using today's utilization technology. If we look at Aspen as a multiple use species it's probably truly one of the greatest multiple use species. We just heard Joss tell us about all the benefits that Aspen provides as wildlife habitat but almost every resource discipline is looking to Aspen stands to provide something to them across the board. Aspen stands are really in demand if you will for a number of purposes. I'd like to first start describing stand conditions. Again these are stand conditions that are probably elsewhere other than southeastern Oregon but nevertheless it reflects some of the development of stands in the western part of the United States where we've learned about how Aspen does grow and behave. First of all Aspen productivity is really a function of available moisture and that can be translated into weather, elevation, physiographic conditions and soils. All of these things influence the available moisture and that in turn influences productivity probably more so than genotype because you can get a lot of genotypic variation but you can still have some pretty good growth or some pretty poor growth depending upon the site that you're talking about. Let's look at Aspen's ecological position amongst western species. If we look at a lot of the western tree species and sort of a layer cake that would go from a warm and dry condition to a cold and wet condition which also translates by the way to an altitudinal gradient. Aspen occurs kind of in the middle. If we would align a vertical line through this we could sort of get an idea of what species Aspen might be associated with and you can see that it is associated with a number of species almost all the species on this chart. It doesn't have a pink color on this chart which means that it is not considered to be climax and that's probably true although Aspen can grow as what we call stable stands which can persist for a long period of time on the landscape and we'll get into that in a little bit. In reality if we look at Aspen on the ground its position really isn't too much different than this layer cake. This is a slide of the Grand Mesa in western Colorado. If we start from the lower right hand corner over here we would see that there's a Pinion Juniper forest that grades into Gamble Oak Woodlands. This emerald band across the middle of this slide right here is Aspen forest and then that grades into the purpleish spruce and fir to the top of this slide. So the layer cake model if you will of Aspen distribution in some parts of the west at least is not that far off. Aspen can occur on the landscapes in huge stands that occupy most of the landscape a large scale landscape mosaic. This is typical of stands in Utah and Colorado again which each have several million acres of Aspen about three million acres alone in Colorado and about a million and a half in Utah. More typically I think in many parts of the west Aspen occurs either in mixed stands with conifers as we see here or isolated small stands that are either surrounded by conifers or surrounded by grassland or by other forest vegetation types. Just for reference this is some data from a study that I did in Colorado a number of years ago. I've updated the ages here to be current ages but basically when I sampled a whole bunch of even aged stands in Colorado I found that if we were to revisit those sites today the average age would be 110 which is considerably older that's what we're probably twice as old as Aspen ever gets to be in the lake states for example. One thing to note here is that I found some stands that today would be over 210 years of age and I know those stands are still there some other researchers in Utah have documented that stands 210, 220 years of age so Aspen can get over 200 but compared to the conifer species it's still a very short-lived species. The other point that I want to make on this slide is that there really isn't, I didn't encounter anything in my sample less than 60 years of age in today's age and that's really I think reflects the history of fire protection throughout the west is that we simply haven't had these large scale disturbances on the landscape that favor Aspen stands that can allow us to see new stands appearing on the landscape. So that's something we have to be aware of because over time our Aspen distribution is essentially drifting to the right in this particular graph. Okay let's move along and talk about regeneration. How does Aspen regenerate? I think almost everybody is familiar with Aspen's ability to regenerate vegetatively but many people aren't aware that Aspen does produce viable seed in fact in a good seed year a female Aspen tree and Aspen is dioecious, you have male and female trees a female tree can produce over a million seed and these are small cottony seeds very similar to cottonwood they don't have much endosperm in fact they hardly have any endosperm at all but they require some very specific regeneration requirements and those requirements are a constant supply of water during the first growing season and bare mineral soil a seed bed to establish and grow on quickly without any competition and what better place to find that than in the gutter outside of my office in Fort Collins this is an Aspen seedling in fact if you look in the gutters and curved sides of many of our western cities where Aspen is planted as a landscape species you'll find Aspen seedlings such as this Aspen seedlings also occur in nature as well in the wild and have been documented recently in the literature having occurred following fires in Yellowstone on a fairly extensive basis Aspen seedlings do occur that's one mechanism by which Aspen maintains its presence on the landscape but the point I want to make here is that we really can't depend upon seedling or seed regeneration to manage Aspen we have to depend upon the vegetative regeneration to manage Aspen and that vegetative regeneration is a phenomena that Josh mentioned called root suckering this is a parent root these roots there's a network of roots that run under an Aspen forest most of the time they're within 10 to 15 centimeters of the soil surface if something should happen to this root it should be cut or the parent tree that's attached to should die if something should happen to interrupt a flow of oxen down this root then bud primordia that are spaced along this root are free to grow and when that happens then it sends up a sprout or what we call a root sucker the other requirements are that that sprout or sucker has to have abundant light to start growing and it has to have somewhat of an elevated temperature so it has to be it has to occur in a place where there's light in some temperature otherwise the growth is not going to persist so that's the mechanism by which Aspen reproduces and it can reproduce quite nicely this is a picture of a group of genetically identical sprouts that have sprouted up around the edge of a parent stand of trees here we term this a clone this is an Aspen clone all of these stems are genetically identical so we're looking at one genetic individual here one genotype but not one physiologic individual that's a very important point a lot of the popular literature has it that we have this large living interconnected organism and that isn't the case it's just as if you were looking at a Jonathan apple orchard for example you're looking at one genotype on the landscape but you're looking at a number of physiologically independent individuals there but when we look at that on a landscape basis we can see in this case the coloration in the fall and leaf out in the spring gives us an idea as to where these clonal boundaries are this is a scene near Aspen, Colorado you can see that some of these genotypes are pretty good size in fact there's a genotype that's been documented in the Fish Lake National Forest in Utah that's 107 acres in size I'm sure there are larger ones out there some place but if we look at the interior of clones we can also see these genotypic features as well here we can see three different bark colors this is sort of a yellowish bark here white in the middle green on this side here is branching characteristics this particular clone has not pruned its dead branches while the one on this side has you have very slender stems that could have some meaning if we were trying to select Aspen's stands to manage for a peeler wood product or a saw log product perhaps here's a situation where we've got stems that are very straight and erect versus stems that are quite branchy and broomy or bushy again you probably wouldn't want to manage this stand for saw logs where this would be a very good stand to manage for saw logs rather facetious to southeast Oregon but believe me it isn't in Utah and Colorado something we do need to pay attention of anywhere we find Aspen is that some clones some genotypes have a propensity to sucker with a minimal amount of disturbance such as we see over here this sucker second generation of suckers growing under this stand where on this stand here there are absolutely no suckers under it and clones like this might take almost a complete stand re-initiating disturbance in order to get any suckers back at all okay that leads me then to Josh mentioned this Serral Aspen versus Stable Aspen these terms have been around a while these definitions are mine to me Serral Aspen is something that will succeed to conifers within one generation without disturbance in other words if something doesn't happen usually fire we can expect that there will be a conifer stand there within an Aspen generation so within 200 years if you will and that disturbance is fire we're really dependent upon fire to maintain Aspen in the landscape in these situations the opposite of that is Stable Aspen in this case I define Stable Aspen as stands which will persist for more than one generation on a site and these may or may not have had a fire origin originally but fire could have burned so hot that there's no seed source there and without a seed source it's going to take many generations for the Aspen or for the conifers to re-occupy the site so we can expect that Aspen will be there for a long period of time several Aspen generations so 400 years or longer probably how might that have... oh first of all here is an illustration of what we're talking about conifers coming up through some of them are already reached the upper canopy we could expect that the Aspen and this forest would disappear probably within an Aspen generation because there's enough shade down in here that the sprouting would be minimal unless we got a stand re-initiating disturbance on this side of the slide you can see that we've got a pure Aspen forest it's a very extensive forest there are absolutely no conifers in it and again we would have to expect a landscape for more than one Aspen generation well then you ask how does that occur how can you possibly have Aspen persist for more than one generation since it's a disturbance dependent species well this is one way right here we can see that this particular Aspen clone has had a suckering event occur underneath it we now have a second story of suckers underneath that or a second generation this particular genotype is one of those genotypes that can sucker and the suckers can grow given a little bit of disturbance and the disturbance could have been something as slight as a late frost or a defoliating insect attack that just removed the leaves long enough to initiate that suckering so this is one way that it can occur if that occurrence is a little more subtle and occurs more on a tree gap basis we get a multi-storied effect as we see here where you've got really multi-storied stands of Aspen similar to the cottonwood that Josh described and these do occur in either of these situations if you encounter those you're probably in pretty good shape because that means the Aspen clone is capable of taking care of itself it really probably doesn't need much management intervention so it's an important point to be aware of here's another instance by which Aspen pure Aspen forests can regenerate we can see on this isolated clone that this side there's a sucker event that's occurred and it's suckering up while on this side it's dying and so this introduces not only the ability of clones in shrub and grasslands to regenerate but a new concept and that is the Aspen clone as a mobile organism on the landscape because these things really then can creep amoeba-like across landscapes over time and while we might see this Aspen genotype here today that doesn't mean it was there 200-300 years ago now the genotype could have been in this landscape for maybe a couple of millennia but it isn't today perhaps where it was tomorrow so most foresters are used to the trees staying put while they manage them but that isn't exactly the case with Aspen at least over time okay going back to my study in Colorado I measured a total of 140 stands I found that roughly 80% of them were even-aged and the remaining 20% were either two-aged or multi-aged so about a fifth of the Aspen stands I encountered in Colorado were other than even-aged and I think my experience since this study throughout other parts of the west has led me to conclude that I think that's pretty reasonable I think at least 20% of the Aspen that I've encountered are other than single-aged so these sorts of things have sort of been going on under our nose over time and we tend not to think about them this is an example of that this is a a clone that's in the median of the interstate of I-70 at Vale, Colorado and about 15 years ago when this slide was taken the over story suddenly died just spontaneously died and you can see this green band here that's a sprout stand that's come in and it happened at about a two-year period and I noticed as I've driven by that over the years how this has progressed today there's a young Aspen stand there all these stems that are dead here since gone down they're no longer visible and it looks perfectly healthy you'd have never known anything happened there 15 years ago so this has also been going on in some cases under our noses but not very much because we would have found them in some of our surveys as far as existing young stands and we haven't found that well let's talk quickly about damaging agents most of you are probably aware that Aspen has a reputation of being a damaged prone species and it really is it's probably one of the most damaging agents is stem cankers or fungal organisms that get into the stem and will ultimately girdle the tree this is a rather slow going canker seratocystis canker produces sort of a slow growing ratty looking target on the stems it does reduce product value for some products but it takes quite a while to kill the stem so it's not all that insidious although it can be a mechanism for ultimate death of the tree if you will this slide shows synangium canker and I apologize to any pathologists out there the name has been changed and I can't remember what it is the name is sooty bark it can kill a tree probably in a dozen years so each of these concentric rings that you see up the tree indicates a year's growth of the canker so you can see how fast it can progress again it doesn't the canker organism doesn't get into the root system and so we could expect new sprouts to occur it would be something that would cause stem mortality not so much defect but stem mortality if you were dealing in a product you know something for a commercially managed stand if you will this is a cytosper canker identified by the little white pimply pycnidia that grow on the bark it is a secondary infection organism for the most part normally it kills trees that are already weakened by something else however we found it to be a causal or at least a contributing organism into a lot of sprout mortality following some treatments that we've observed throughout the west so it can be a problem especially with regeneration but normally it's thought of in mature trees as a secondary infection agent this is cryptosperia canker these sort of oranges notice there's sort of a really fast spiral here it's a very fast growing canker it can kill trees in a year or so you know a good way to initiate salvage sales I guess this is a rare one in the west this is hypoxion canker it's quite common in the east and causes quite a bit of mortality and quite a bit of consternation to managers there but it's sort of an anomaly in the west it does occur out here but it really isn't that big of a problem in many areas before I move on one last mention on insects and diseases there are a number of insects that affect aspen the fuller defoliating insects are probably the biggest problem this is porous tent caterpillar these insects can multiply their populations can grow so fast that they can literally totally defoliate a whole landscape in a growing season I've seen maybe 15 square miles defoliated all at once these will come back quickly once the population crashes although multiple year events can cause a damage of the overstory and a dieback of the overstory but in my experience all of these areas always sprout back so if you're dealing with a stable aspen stand situation it probably isn't that big a deal if you're dealing with a mixed stand serral aspen you probably are going to lose quite a bit of aspen because the conifers are shading out the suckers in those areas stem rots are a big deal in commercially managed areas and in recreation areas where one of these things happens on the head they're not that big a problem in some of the new with some of the new utilization techniques because techniques such as wafer wood and excel shear can take up to 50% rot in stems and so this isn't a real problem with marketability with some of the newer utilization techniques it is for traditional roundwood, peeler logs, saw logs that sort of thing so again it's all a relative thing I guess okay I'd like to talk a little bit about deteriorating stands that's one thing that we really do need to recognize as managers to sort of categorize aspen as to whether we need to intervene and do something and these would be stands then that really are falling apart and they're not spontaneously regenerating we need to try to recognize these and a good way to do that would be to look at the structure of stands as you can see here this is a very open stand you can see right through it it has a low basal area there is some mortality I don't know if you can see over here on this side let me come out here just a little bit there is some mortality over here but there's no suckers underneath there's no regeneration here mortality is occurring but the stand isn't regenerating should be cause for concern here's a situation where we see a lot of elk barking on a stand here again there's some mortality this is a dead stand that's dead that's dead that's dead there's all kinds of dead stands in there but again no suckers in the forest floor so something is going on here that's causing the stand not to regenerate probably what is going on in this case would be that the stand is attempting to sucker but the animals are eating suckers one thing we need to remember is that in many of our western landscapes animal populations today are much different than what they were at the time that this aspen-rammit generation that we see on the landscape was initiated so we've got different animal population situations today than we probably had 110 to 200 years ago throughout much of the west here's a situation where this stand is again an open stand is deteriorating some let me zoom in on this a little bit you can see there's two green clumps here three actually that's the only aspen-regeneration in this particular area cause for concern some things going on and we need to find out what here if we were to to attempt management before we could attempt management thank you we need to lighten this up a little bit in this case this stand is trying to regenerate but all these stems here are dead sprouts that have occurred sprouted up along the edge of this clone in this case they died because of elk browsing so here's a clone that is stressed enough that it's spontaneously trying to regenerate but the animals are eating the sprouts again it's a cause for concern first of all the stand is trying to regenerate that means that something is probably wrong with the stand and secondly the regeneration is dying we need to be aware of that what the big deal about this is is that if you have especially in situations where you've got isolated aspen clones like this if you lose those stems such as happened here this particular clone died about 10 years ago and you don't get sprouting or the sprouts can't persist what happens then is you've lost the genotype and if you lose the genotype you can't get it back because you have to remember in many of our western landscapes these genotypes have probably been there for at least a millennia maybe longer quite frankly probably much longer in many cases so if we lose one of these genotypes we've really lost something and it's a pretty tough deal to try to reintroduce aspen through artificial reforestation we'll discuss why in a minute here okay regeneration silviculture how do you go about regenerating aspen we know now how the beast behaves let's take advantage of some of those characteristics and see if we can deal with them then in our management activities that we choose first of all aspen is an intolerant species I haven't mentioned that yet but that means it likes sun it's intolerant of shade it regenerates vegetatively by root suckering it self-thins and by this I mean it behaves differently than conifers conifers recruitment follows a logistic population curve and you increase the number of individuals gradually over time through seeding until you get full site occupancy with aspen it's exactly the opposite what happens is that you will have the maximum number of stems on the site in that generation the first year following suckering and it's a downhill slide from then on in fact it follows a negative exponential decay curve over time so you're always losing stems from an aspen generation an aspen population and that's going to occur then until something happens and you get another suckering event so we have to be aware that when we regenerate aspen we have to try to maximize the number of suckers that we're going to get in the first year because that's all we're ever going to have to deal with for that next generation and you're going to affect the character of your next generation if you don't try to maximize suckering finally we have to be cognizant that it's susceptible to disease as we've talked about one of the things that you can use is commercial harvest and I realize that's rather laughable in eastern Oregon but I assure you there are parts of the world where aspen is commercially harvested in Utah and Colorado in Wyoming and very successfully this is a slide of an aspen it's not a clear cut it's a clear fell coppers unit because we're dealing with a low forest system and the civil cultures and the audience could appreciate that the rest of you can ignore it basically this is a commercially harvested unit in central Colorado that was harvested with mechanical equipment in the dormant season in the winter time so we didn't get any compaction damage it looks like a field of wheat there are 65,000 plus suckers per acre in this two year old stand it's just beginning just beginning it's second or it's third growing season here you can see from this that if done properly and if you utilize landscape architects in your design there's you can really do a lot with a clear fell system you can blend these openings into the landscape to regenerate very quickly they quickly assume the crown character and the colors of aspen especially in the fall and so you can actually do some positive things through clear cutting on landscapes if you've got the aspen stands to deal with again this was a 20 acre unit there were probably several hundred acres of aspen pure aspen on this site that they could place these units in so you have a lot more to deal with one thing that I've tried to study in in the mid 80's in Colorado was to use a bulldozer to tip aspen over because we had some stands that were not at that time commercially operable and we wanted to see can we just get in there and tip the trees over and use this as a cost effective method of removing that parent generation and starting a new one because we wanted to break up the age class diversity in some of these landscapes this is a slide that shows how one of the replications of that study you can see on this side this was a side that was dozer tipped this was a side that was chainsaw felled you can see the stumps there so the dozer tipping didn't disturb the land very much it just tip those trees over just separated the stumps from the roots and that was it these fence posts here there's a three wire fencing treatment that we had and then we left the slash in the back on both of these treatments as well to see if leaving a slash on site would have an effect the big result from this was if you look at this slide after five years the green is dozed red is cut after five years regardless of the treatment whether it was fenced or not we got significantly more suckers in the dozed area than we got in the cut area and we also found a fencing effect here this is fenced and unfenced this was where the slash was left in this case so leaving a slash did suppress suckering because of the shading so that didn't work too well but the big point was that we got this tremendous stimulation effect and I hypothesized as scientists are prone to do that this was probably due to the fact that we had removed those stumps completely from the roots and any oxen that had been left in that tissue of the stump which is quite a bit of biomass was removed along with it and so these roots got no oxen whatsoever it totally interrupted the flow and that really gave these bud primordia kicking the pants to get going so in order to test that we decided to do another study in Arizona a ripping study let's not remove the stumps let's just remove the roots and try to to leave some of the stand there in this case we had a very open aspen stand a very park-like stand that had been partially cut about 10 years prior to this treatment and if regeneration occurred and it probably did it didn't survive because of animal browsing so what we did is we went into this area we fenced it first of all and then we went around each of the trees staying about 25 feet away with a ripper in this case we had three teeth on the ripper and we just separated all those roots again and these roots are within a foot of the surface so you can easily get them with any kind of mechanized equipment that could get that deep after three years this is what we had you can see the open stand there we had enough light down in through the canopy that we were able to get the light and the temperature increases we needed and we've got some suckers in there they're now up to 10 feet tall not too many only a couple thousand in this area but we have a regeneration on this site where before there really wasn't much chance of doing it and we wanted to do this without cutting the mature trees because this is a site in Arizona where this was the only aspen in the landscape and the wildlife biologists were very concerned that we're going to be eliminating bird habitat and cavity nesting habitat if we were to cut these large trees to regenerate the stand and so we figured out a way where we applied what we learned from the bulldozing study successfully figured out a way to sort of have our cake and eat it too here and it worked very successfully this is a picture of another technique the same technique if we could lighten that up a lot there we go edge ripping in this case we drove the bulldozer just along the edge of the clone here this is an isolated clone in pine type again in Arizona it was on the edge of a meadow these suckers are one year old this slide was taken three weeks ago these suckers out here go out about a tree height and a half away from the existing clone over here so effectively what we've done here is we've not only regenerated this genotype while keeping the mature stems but we've expanded the acreage of aspen in this landscape quite a bit in this particular case we probably increased the area of this very small clone and this is the whole thing right there by a factor at least three so you can increase site occupancy by doing something like this and again anything that would remove several of those routes would do the job in this case we just had a single tooth on the ripper bar of the tractor to do that the effect then can be that you can actually mechanically through management do what has occurred in this case naturally and that is you get an edge suckering event away from this clone if you have growing room around the clone you can actually expand the acreages of aspen in the landscapes over time so our ripping that last slide I show you with the ripping will look like this probably in 20 years as it expands this is a natural occurrence here but we should get the same effect I mentioned that you have to have light around and what we've done is get into that I'll talk a little bit about fire fire is one of the natural methods by which aspen regenerates so is there means by which we could apply that in conjunction with other silviculture prescriptions and the answer is certainly there is pure aspen as these poor souls have found out doesn't burn very well it's actually used as a fire break by firefighters because there isn't the fuels under pure aspen stand to really carry a fire through it's not a mixed understory of conifers as we see here the serral type situation or if you've got shrubby understory can we lighten it up a little okay it's not going to go in this case sage brush you can start the fire in the sage brush and run it into the aspen and you can get a pretty good situation this is actually that mixed stand that I showed you in the slide before last these suckers this slide was taken let's see June the 21st this year these suckers were leafed out about a week and a half they were beginning their second year's growth and you can see that this was all essentially the first year's growth in this stand following a prescribed fire and did a very good job of killing the overstory removing the conifers and regenerating the aspen it was a pretty cheap way to do business too and again takes advantage of mother nature one thing that we've tried in Arizona was to apply a prescribed burn to logging slice where we'd actually gone into this area and we'd removed pine and then we used the slash from the pine logging to run a fire through here and as you can see we didn't kill all the stems we killed a few but we didn't kill all the aspen stems but this is what happened these are one year old sprouts the tallest ones were five and a half feet tall this one on the foreground here the leaves on that are seven inches in diameter if you could believe that huge it looks like a tobacco plant out there if we were to pivot 180 degrees from that and look into the other side of the study this area from here on this is burned here in the foreground but from here on across here that was our unburned area the same treatment of removing conifers we got very little sprouting what we did didn't grow near as fast as that where we'd burn so we're obviously getting a fertilizer effect from the fire as well as an additional stimulation effect from the fire and that brings me then to the other point of can't remove competed conifers and I apologize for the spelling there I did this real quickly the extreme case of that is another instance in Arizona where we looked at the most extreme situation we could find where aspen was growing with ponderosa pine and it consisted of a clone on the Kaibab National Forest that consisted of five aspen trees these two trees here there were two or three dead trees but this was the whole clone it was on a rock pile west of Flagstaff about 20 miles there was not another aspen in this landscape within four miles so this was the very last presence of aspen in this landscape there was pine growing all around this so what we did is we removed the pine and we fenced it as you can see here with the fence that's all we did we didn't kill any stems or anything like that we just removed the pine and we just fenced it to protect it from animals and this if we could lighten that up as much as you can please this is what it looks like after three growing seasons these are the same two trees in there same rock pile we've counted every sprout inside this quarter acre fence we now have 227 surviving sprouts the tallest of which is here in the foreground all that's a third the height of the parent tree in three growing seasons and all we did was remove the competing conifers and fenced it the aspen did the rest and this is the most extreme case that I've encountered as far as being able to bring things back okay there's a number of things that can affect regeneration once we've got it established aspen is disease prone susceptible things like snow a lot of these crooked stems here due to snow and disease this is a cytospera infected stem here that can really affect some populations but we can't do much about those because those are natural things that occur naturally in these ecosystems the one thing that we can do something about is animal browsing and that throughout the west I think is probably one of our biggest problems and will be when we get into the serral stands which constitute a lot of real regeneration need is and browsing we've learned is really a function of a number of things the location of the aspen where it's at in the landscape the season that the animals are on the site using the aspen the clonal preference now some clones are much more tastier to animals than other clones there's a decided clonal preference and you'll see a lot greater damage on some clones than others and we'll see that in a minute here and what other available forage in the ecosystem some ecosystems there is no other available forage riparian areas are a very good example as Josh showed us and that's where we have to be really sort of add all these things up and figure out what our potential for browsing is before we attempt any regeneration now almost every aspen regeneration area that I've been associated with has had some browsing in it it's just almost universal but it's not a problem as long as their browsing occurs on lateral branches the problem occurs is when the animals get to the the central growing axis of the plant and tend to stop the growth there in this case elk have literally broken the main growing axis of this stem they've broken it off at about 5 feet off the ground and to get at the leaves on the top and subsequently these stems get infected and this is what happens here over time I'm standing next to one of the few surviving stems in this particular stand in Arizona I might explain how this got to be we did a study down there a fence removal study where we wanted to find out how long we had to have a fence up before we could safely remove it we had a stand that was consisted of 20 to 30,000 sprouts per acre at age 5 the tallest of which were 13 feet tall most of them were about 8 to 10 feet tall maximum diameter was just under an inch we took the fence down after 5 years the elk moved into one genotype one clone in this area out of probably a half a dozen clones and they really liked it and they did this breaking and it looks like somebody took a highway mower and went through here at about 5 feet off the ground broke all the stems off this brown that you see there was a portion that killed every one of those stems because the top was broken the only ones that survived were the ones that were big enough that the elk physically couldn't break them off and those were an inch and a half or larger in diameter so we haven't lost the genotype here there are still probably 2 or 300 stems in this clone that are still alive but we've drastically changed the character of the genotype for the next generation what would have happened had we not had the fence there we would have probably had what is known on the coconutal national forest as the aspen stump meadow this was a stand that was harvested the same year that the previous stand was harvested it was not fenced it probably did sucker the animals got the suckers and today there's nothing there but stumps but in the meantime the roots have died so even if we wanted to we couldn't put aspen back on this site it's sort of like Humpty Dumpty all the king's horses and all the king's men can't put the aspen back one thing that the cocanino has learned is that they have to fence in their particular situation because they have high animal populations and not many aspen acres and every time I mention fencing to somebody that is in that situation I hear the cringes and it's something that we need to face in a lot of our aspen ecosystems in the west we're going to have to be faced with this because that's the only viable alternative and it works very effectively the cocanino here is using a two a hogwire that consists of two flights of hogwire steel posts they also utilize existing trees they use I'll get this out a little bit they use put a a board nail to the tree or wired to the tree here and then they nail the fence to that so that they actually they nail the board to the tree that way they don't have any wire that grows into the tree and so they can utilize living trees as fence posts without any future damage to those trees they try to get long flights they're building these fences for $6,000 a mile and they're going to have to keep them up about 10 years and that requires maintenance but we're faced with that if we're going to get asked and back you can see what happens if you don't have a fence back to the fence removal study the genotypes that weren't browsed because they weren't tasty the elk moved to those after they finished off the first one or the ice cream clone but in the meantime those trees hadn't managed to grow large enough that they're now too big for the elk to break and so this is what it looks like in fact a month ago when this slide was taken we now have about 15 18 foot tall sprouts most of the dominance are at least an inch and a half in diameter but we get an extensive browse line but it's just the lateral branches that are being browsed we have very little mortality in there we're still carrying over 10,000 sprouts per acre in this area so I think the last one we've learned there is that if we leave the fences up long enough we can get through this now we're beginning to see barking occur in here and the question is what's going to happen from the barking so we're going to have to follow this over time to see if that unravels the stand later but I feel comfortable with this because we've got the numbers here and that's again numbers are it when you're trying to regenerate aspen the more sprouts the better in conclusion managing aspen is really just like a chain you've got to and it's only as strong as the weakest link you've got to first of all understand what you're dealing with what it needs and that comes in with the prescription process here you've got to come up with the right prescription then you have to treat it properly and you have to make sure the treatment gets applied properly in the proper manner and finally you've got to do the monitoring you've got to follow up keep the records to make sure that everything is going okay in the next generation if you don't the whole thing can fall apart so with that I'll be happy to entertain any questions questions yeah we've got an aspen patch here that we're trying to regenerate we've got a lot of real dense grass and four plants underneath it are these going to compete with the suckers coming up at all it depends upon how dense dense is okay I had an experience in Colorado in an area that we harvested in 1983 and it was a very small clear cut but it was fenced and it initially sprouted well but 1983 until this year was the wettest year we had on record now 95 is wetter than that but as a result of that we got tremendous understory growth now this was a grass and a cow parsnip understory but the understory was so dense in excess of 6,000 pounds per acre that when we had a snowpack that winter it took the aspen sprouts with it and they were under maybe 6 inches of decomposing grass they didn't survive and in that case we got essentially a failure we have maybe a few hundred sprouts per acre available there today so yeah it can if you've got extremely dense understories but I'd say in the average situation it isn't going to be that big a deal because again these things can grow 5 feet in one year and especially if we do something like a site prep to burn perhaps to get them going yeah fall burn or whatever you shouldn't have a problem with it and again our prescribed burn in Arizona worked just beautifully in that respect let's go to our remote sites because we can ask Wayne questions after the session so let's get the remote sites now okay go ahead and I saw that was booked and it is in root rod and you're on the right track and it's suspecting a root rod and usually that's the sign is you get wind thrown trees with no root rod turned up it's they just look like somebody almost like a beaver chewed them off you know there's nothing there there's no roots that are attached probably is a root rod epicenter in my experience those usually don't encompass large acreages in some cases they can wipe out most of a clone there isn't anything you can do about it you're just going to probably lose a portion of that genotype and you probably won't get any any suckering if you do look around and see some suckers are started you may want to apply some protection if this is a rare clone in the landscape but a lot of these root rod epicenters just don't come back and they're just another gap forming process I have a curiosity question too there's a couple places that I saw the regeneration that was right along the well decomposed gloves when you say that one of the requirements which is under the decomposition of that wood can elevation and temperature it's an interesting theory and I agree it could be another possibility could be that if that law afforded any protection all from browsing animals that's another reason that you might see the suckers there if the you saw browsing on the suckers or evidence of browsing that probably was a reason for that another possibility might be that that particular site retained enough moisture that you're actually looking at a seedling again I'm not familiar with what sort of moisture regimes you would get throughout the summer here but if you would get enough periodic moisture that that could be a seed bed for an aspen seed you might actually see aspen seedlings in that case okay thanks Bob next question from the remote side this is Seneca if you if aspen or daetian would the members of the genotype be single sexed or could there be both sexes in one genotype no they'll always be single sex you have male clones and female clones and unfortunately a lot of people that dig aspen to put in their yard picked the wrong sex and they get the females and they have cotton blowing all over town other questions go ahead are you aware of or is there any research going on about the alleopathic effects of aspen on my perian sites or aspen I'm not aware of anything along those lines no other questions from enterprise go ahead also are you or possibly Josh aware of any studies or observations that have been made of particularly bird use of aspen stands having different kinds of defects in them I can imagine the rotting bulls of course that provide more habitat for woodpeckers and other cavity nesters but in general control of the agents that affect the aspen or availability of habitat any relationships you're aware of Josh is pushing his mic but no you're not going to say anything Josh just let go of it now Josh he's got to try it out maybe you have to hold it down they said just push it it appears that woodpeckers are using the softest aspen which are usually those that have undergone I've been attacked by certain pathogens and stuff and I'm not aware I'm not sure of the exact type of pathogens that create the softest trees but there's definitely a preference for damaged aspen at least in Arizona where some research has been done on that do you get that? yes thank you more questions? go ahead Bob it seems that a lot of at least in my experience in Colorado in the southwest when you get a concentration of cankers in an area it does seem to localize sometimes in one genotype but sometimes across a genotype but in a localized area and I've always advised managers on an awful lot of cankers in an area you probably should think about regenerating it through a clear fell because that will allow you to get rid of some of the infectious spores at least and at least start with a healthy stand now where they've done this in some of our commercial harvested areas in Colorado where they have the means to do that it's been very effective and there's no sign of cankers in any of the new stands and some of these stands are now 15 years old so they're large enough that the cankers could infect them in the case of cytospera canker as I mentioned that does affect the regeneration and it can wipe out stands of regeneration and has in our experience normally that occurs in situations where the regeneration is stressed from something else either too much moisture not enough moisture too much browsing snow breakage or snow damage or defoliant or something has got in there to provide a pathway for the infection and weaken the stems and then the regeneration will get wiped out but usually a good practice is if you've got large concentrations of cankers you probably should think about regenerating a stand I know exactly what you're talking about I've seen the same phenomena in Colorado and the answer is yes they can spread into other areas that create sort of almost like a crumholtz effect if you will in conifers that ultimately the aspen becomes self-protecting enough that if the edge sprout then those stands the stems that are a little younger on the edge can then survive and grow to be a tree like form. Another thing that can happen is that very severely deformed goose neck sprouts can actually grow out of it over time. I often wondered for years how come I was looking at a lot of crooked sprouts and these newly regenerated stands yet all the mature trees around there were straight and I figured the climate hadn't changed that much and one year the ranger at Mancos was splitting firewood and he split an aspen bowl right down the middle and he happened to be working with a butt end log and there in the middle of that log was a typical goose neck just like under your sink at the pith of that stem and that answered the question that aspen can grow out of it and in suing years since that time I've actually revisited sites that were severely damaged maybe 10 15 years ago and today they're just fine so they can grow out of snow damage but it is another mechanism by which this self thinning this exponential decay curve that I mentioned happens over time. Let's go to LeGrand now for a couple of questions for the benefit of the remote audience any questions here in LeGrand? Yeah, Josh. Yeah, how important is the individual genotype in aspen given that you do say there's sexual reproduction as well. Do we have any idea of how many new genotypes how much that's accounting for creation of new genotypes versus we talked a lot about how we're losing a genotype so how important really is that loss of that genotype? Well I think it depends upon I think you know it's a matter of a big deal. If you've got a landscape that's got hundreds and hundreds of aspen clones in it you lose one no big deal but if you've got a landscape that only has one aspen clone in it you lose it that's a big deal you know and that two stem clone in Arizona that I talked about that was a very big deal to try to save that and we spent a lot of the taxpayers money doing it and fortunately we were successful so it's a matter of the situation you find it in. You know there's always because it's been documented that seedlings occur there are always some new seedlings growing and as you recall that small isolated clone that was spreading that slide that sort of phenomena is going on all the time in our western landscape so where it can but I think what we have to do is identify those situations where it's really crucial that we do retain genotypes and worry about those and just don't worry about the rest of it it'll take care of itself and I think there's plenty of genotypes out there to maintain a good gene pool too we're going to have to cut it off here with one more question from remote site anybody and Baker go ahead you know there's a critical amount of conifer crown closure that would inhibit suckering or establishment of a new clone that's a good guess and I think again it depends upon the clone because some clones can sucker with quite a bit of shading and others you've got to totally open them up so it just depends upon the particular situation you're in normally I think you would if you create a canopy gap you can get suckering in a gap as small as tree height wide and do it quite nicely so you don't have to create large openings but you do usually have to create openings alright let's thank both of our speakers for tonight's presentations