 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 4 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. And 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, 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 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 first of the three sessions looks at two subjects, the historical and present-day distribution of quaking aspen and black cottonwood in the Blue Mountains, and the ecology and watershed functions of western cottonwoods. I hope you enjoy it. Quaking aspen, which is populous tremuloides, scientific name, and black cottonwood, populous trichocarpa, provide tremendous aesthetic enjoyment to us here in the Blue Mountains, particularly this time of year. When the colors are turning, you see a lot of bright golden colors of both cottonwood and aspen out in the forest. We also enjoy them for wildlife viewing because they're disproportionately attractive to wildlife, mammals and birds in the Blue Mountains. They're very nice places to rest and relax and enjoy nature. Distribution of these two species, unfortunately, has decreased somewhat in the last 100 to 150 years. Accounts of Euro-American explorers, settlers, and land surveyors from this time period indicate that the aerial extent and distribution of stands of these species were greater than they are today. In addition, numerous present-day land managers and land owners have reported the decrease and decadence and disappearance, in fact, of stands of cottonwood and aspen. Both of these species are fairly short-lived. They have about 100 to 120-year lifespan, and therefore it doesn't take a whole lot of pressure on these populations to decrease them. Quaking aspen. The exact acreage and number of stands of quaking aspen from the historical past, and by historical past I'm specifically referring to the past 100 to 200 years for which we have actual records, written records and oral records, isn't really known. We can go back and look at land survey records which have a lot more information about specific locations than some of our settlers and explorers' accounts, and these records can provide some information. They're not specific in telling us the acreage, the total acreage of these species. They would probably be useful to somebody who wanted to spend a couple of years figuring out the exact historical extent. Unfortunately, I didn't have that much time. In the Blue Mountains, aspen clones generally take the form of single stands, whereas if you move farther east into Utah and Colorado and places where aspen is really well known, it can cover an entire hillside. And there tends to be a dominant cereal tree, that is, it comes into a forest and then is overtopped by other trees such as conifers, and the shading causes the aspen to go out. In our area in the Blue Mountains, aspen tend to occur as single clones, such as the one you see in this picture. One clone usually equals one stand. Most of the aspen we have occurs in topographic areas of Douglas fir and ponderosa pine, but it also occurs in sagebrush zones and grand fir to a lesser extent. Specifically aspen occurs in areas of locally higher soil moisture. That is riparian areas of family wet draws, basins, the edges of meadows, and ground water seeps. And these are areas where more water is collecting in the soil than the surrounding areas. This is where we mostly see aspen. And stands, unfortunately, in all of these situations are decadent and disappearing. Factors that have had the greatest influence on the change in historical distribution of aspen are, first of all, the reduced occurrence of fire, and I know you've had other seminars speaking about fire in the Blue Mountains and the fact that we have less fire than we had 100 to 150 years ago. In this stand you can see a small number of mostly lodgepole pine coming in under this stand. It's a fairly small stand at this point anyway. These lodgepole pine will grow up and eventually shade out the aspen. If a fire doesn't come in and take out those trees. When fires do come into these stands they'll kill the older trees, the overstory trees, but they'll stimulate suckering of the aspen rooting clone. By clone that means that all of these above ground trees are connected to each other. That means one organism with one common root mass, the root mass is under ground and will send up suckers in all directions. If this stand is burned and all the overstory trees die then the plants will immediately sucker up and they grow so quickly that they can grow faster than the conifers and hold their own for a good deal of time. Here's another stand you can see with coniferous trees growing up in the middle of them, of it. And here's what happens. Here we have one lonely aspen tree sitting in the middle of these conifers. In this situation we have two dead snags, so we know snags are good for wildlife but in fact we've lost this clone which is kind of sad. Second factor we have that has influenced the decline of aspen is overbrowsing. Aspen is in the willow family and you've seen willows being browsed probably if you're out in the forest at all. Aspen can take browsing, it's not a problem for aspen but if it's overbrowsed it can kill the plants. Here's an example of a small group of suckers that came up probably 10, 15 years ago and you can see how small they are. They're about two feet tall. They've been browsed so heavily that they haven't been able to get above the browse height and put any real height on the plants. Here's another tree that's been more or less bonside. This happens quite often. Sometimes this is from cattle, sometimes this is from elk, sometimes it's from deer, it's really a combination of all the ungulate species that we have out in the forest. After all the mature trees have died in a clone, it's up to the suckers either to shoot up, produce leaves and photosynthesize and produce sugars that are sent down to the roots of the clone or the clone will die because there's only a limited amount of carbohydrates stored in the roots of the clone and once if those suckers cannot get up high enough, produce enough leaves and fix enough sugars to keep that clone alive, it will die. Here's a situation where we have a stand, it has a few conifers, you can see in it, but for the most part it's open. Unfortunately, we have no younger generation growing up. To show you that in fact this can occur, this is a stand on the North Fork John Day Ranger District on the Umatilla National Forest that's been fenced and it's been fenced from not only cattle but also elk. Deer can probably get through this fence, but we've fenced out quite a few of the animals and you can see the younger generation that's growing on the edge of this clone. And here's another example. This is a fairly stark example. There are some plants growing outside of that fence but you can't see them in this picture because they're so small. Here's an example of a healthy stand with three generations, three different age classes. This is on the Walla Walla Ranger District. This stand is right near a road and when the road was put in, the younger generations started to come up because the elk that used to pass through this meadow and feed were scared away by the road traffic. The third factor that has influenced the decline of aspen is the possible loss of habitat. And I'm referring to areas, I mentioned that aspen grows in areas of locally high moisture and I'm referring to areas where we have streams that have been down cut and a water table has dropped, reducing the amount of soil moisture that we have and possibly losing areas where aspen stands can become established. Second species we have is black cottonwood. Like claking aspen, the exact historical distribution of black cottonwood is unknown. It might be somewhat easier to reconstruct this historical distribution because we have more of an idea, well, in my mind where specifically black cottonwood will grow. Whoops, let's go back. Again, land managers are reporting the decrease in stand extent and total population size along streams where black cottonwood occurs. Historically, black cottonwood was prominent and still is prominent in the middle and lower reaches of many of our major river systems, including the Grand Ronde, the Wenaha, the Snake, the Imnaha, the Powder, the Burnt, the Malheur, the John Day, the Walla Walla and the Ducannon Rivers and some of their tributaries. Unlike aspen stands, cottonwood stands are not a self-perpetuating system. They do not have a large clonal root system that will regenerate suckers when the older trees die from disease and fall down or they're cut down or burnt. Instead, a population of aspen can be self-perpetuating in a valley that's open enough for that species to occur. The population is perpetuated by the stream, constantly scouring and redepositing mineral materials on which cottonwood seeds and branchlets or little pieces of cottonwood can get established and produce a new stand. So in other words, in a stream reach, you have a series of different age stands of cottonwood. The streams in these valleys flood frequently, at least on a geologic timescale, perhaps not every year, but every five years or 10 years or 20 years. And a freshman mineral sediment, mineral sediment that is provided by flooding is where the cottonwood seeds become established. I said the valleys had to be open and broad. Cottonwood is a shade intolerant species and a valley either needs to be broad enough to allow a lot of sunlight in or the vegetation growing on the side slopes of the valley has to be open enough such as sagebrush or open pine or Douglas fir that there's enough sunlight coming in to allow the cottonwood to establish and to thrive. In the Blue Mountains, most of these reaches are below 3,500 to 4,000 feet. On smaller tributaries above these elevations, we do sometimes see sporadic cottonwood stands or single trees, maybe two trees. Usually this occurs where we've had some kind of disturbance. If you drive around in the forest very often where there's dense coniferous forest, you might cross a stream and where that road crossing is sometimes you'll see a stand of cottonwood that's developed. What's happened is you opened up the forest canopy. There's usually been a lot of disturbance of the stream and a lot of sediments been laid down. There's a lot of gravel and mineral material that's been exposed and cottonwood seeds come in and colonize that area. Those stands, however, are generally not self-perpetuating. Most of them will have conifers grow up into the middle of them and they'll overtop the cottonwood, shade them out, and you won't get regeneration of new trees. Okay. Several factors have influenced the decline of cottonwood in the Blue Mountains. The first one is the loss of habitat. And loss of habitat has three factors to it. One is land conversion. Many of the areas I said where cottonwood is was really prominent and still is prominent are below 4,000 to 3,500 to 4,000 feet. Most of these areas are urban areas or farms or ranches. And so a lot of our fertile cottonwood valleys have been converted to farmland or cropland, pastureland or urban areas. And by doing so, that's excluded the cottonwood from those areas. Of course, cottonwood can't become established on asphalt and if you're a farmer or a rancher, you certainly don't want a whole stand of cottonwood shading out your pasture, grasses, or your crops. The second loss of habitat comes from the conversion of the channel system. Channels that are braided have a lot of energy and a lot of sediment moving around are very good cottonwood channels. And here we have a valley system where we used to have probably more than one channel where you can see the old line of cottonwoods along this channel. Because you don't want to have multiple channels in your farmland or your ranch land, most of these stream systems have been moved into one channel that's easy to control and you know where it's gonna be, you know where it's gonna move, you don't have to cross it with machinery and it's not flooding your plants. Here's another situation where we have a road that was built right down the floodplain of this stream and it's essentially changed this channel from a reandering channel to a straight shot channel. There's really not much room for cottonwood to become established here. It's just gonna be in a linear gallery. I have an example here. This was taken from the general or the government land office surveys. On the left you can see the 1880 survey. This is the junction of Eagle Creek and the Powder River. This is right near the town of Richland in Oregon. This is on the south side of the Wallows and it doesn't look like it's really very visible but if you look inside the red line on that sketch to your left, there are all kinds of little trees drawn in there. That was done by the surveyor and when I went and looked at his survey records, those trees here he was referring to were cottonwoods. So we had a huge gallery of cottonwoods running along this confluence of these two rivers. In addition, you can see the squiggly lines of the old channels that used to run down there at Lower Eagle Creek. And then on the right you can see the 1982 aerial photo. And in this photo there are two things to look at. One is that we've lost several of the former channels. We have just one channel running through there and secondly we only have a narrow gallery of cottonwood that run right along that main channel. We don't have nearly the extent that we used to have. Also to the very right of that picture in the dashed yellow line is Brownlee Reservoir and Brownlee Reservoir takes up area that used to be occupied by cottonwoods. On the left side I've drawn it in where it is you could see it's covered part of that cottonwood gallery. Third possible loss of habitat is from the reduction of establishment substrate. It's kind of complicated phrase but what that means is that we've lost, in some areas we've lost material through the building of reservoirs and dams and other flood control measures that might have been washed downstream, redeposited and provided substrate for cottonwood to become reestablished on. This is a much smaller portion of our area but it has occurred. Second factor influencing the client of cottonwood is over-browsing and just like aspen cottonwood are very highly desired browse plants by ungulates and so they've been heavily browsed on lands all over the Blue Mountains. Here's an example of a gravel bar, a large gravel bar that's an old cottonwood that you see on the far side of the stream. This gravel bar one would expect would have a large number of young cottonwood seedlings established on it as well as willow seedlings but right now it's quite bare. Here's another shot of the gravel bar across the stream, there's really nothing growing on this bar at all even though it's wide open, there's no shade, there's seed source in the stream. By contrast, this is another gravel bar, this is actually on the Grand Ron River by, I think it's called Redbridge State Park, it's not a national park and all over this gravel bar you can see cottonwood seedlings that have become established. It's the same situation, we have no shading we have a seed source but we don't have animals feeding on these cottonwoods probably because it's about 100 yards from the parking lot. Here's another situation where we have cottonwood seedlings that have become established, this is another cobble bar really, these are larger course fragments, this is on the Amnaha River and it's an island bar and so it's not very accessible to large animals and so these plants have been able to become established. Third factor influencing this climb, cottonwood once again is a conifer succession, cottonwood is also a fairly shade and tolerant species like aspen and with the loss of fire some of these low elevation, broad flood plains may not be able to support cottonwood for a long period of time because conifers have been able to grow in and shade out the site. In addition, I already mentioned the higher elevation locations where you have a cottonwood, small cottonwood stand that'll become established but really it's a conifer site and the conifers quickly come in and overtop the cottonwoods. Here's an example, this is a grandfather growing in right underneath this cottonwood and it probably only take about 100 years for that stand to go up. The fourth factor that's influenced the decline of cottonwood historically has been the harvesting of older trees, stands that have already been established and over time cottonwood's been used for a variety of things. I think originally when settlers first came in they probably used it for firewood and maybe for making furniture and barrels and crates and things like that. Recently we've had more harvesting of older trees that can be sold for pulp and it's also used as firewood. Harvesting of older trees takes away some of the seed source that can produce seeds for younger generations to get established. And this is an example of an area where we have no regeneration and we have few older trees left. The stand is starting to die out here. We just have one tree and here you can see what remains. There's just a snag, cottonwood snag or two snags and black hawthorn is now growing on the site. So on this particular stretch of stream we've lost cottonwood for the time being until we can get some new plants coming in and establish them, we won't have it. In conclusion I'd like to say that what I've said is really about the change over historic time of the populations of Aspen and Cottonwood. That doesn't mean that that's the future of Aspen and Cottonwood in this area. In fact, many people are concerned about Aspen stands and there've been a lot of efforts now to fence off Aspen stands, to cut out conifers and to allow regeneration to take place. Cottonwood I'm not so sure about. I don't really know what kind of projects have been ongoing. But it's not that hard for Cottonwood to become established, it's simply a matter of allowing the young plants to get established on bars or fresh substrate and allowing them to get large enough so that they're no longer within browse range of our major ungulate browsers. So thank you. Okay well please if you just want to stay up there and maybe you can feel a few questions. And if the audio people can hear me at the remote sites I'd like to have them bring up the audio bridge now if they could. We got done a little bit earlier than anticipated so we'll have questions here locally and then they can be working on the audio bridge at the remote site. So anybody from the local audience have some questions for Elizabeth? Yes. I have a question. You mentioned that part of the reason for the decline in black cotton was the fact that older trees have been harvested. My question is what's an older tree and at what age do cottonwood start to produce seed? I don't know what age they start to produce seed. Probably Dr. Heilman can answer that question for you. By older trees, I mean it seems that most of the trees that are harvested are at least 80 years old. 80 to 100 years is what I'm referring to. Any other questions? I can break in here. Black cottonwood starts to produce seed about eight years of age. It can actually be earlier if the tree is particularly vigorous. We have a nice stand of aspen at our place and we'd like to spread them around a little bit. Can we do that with cuttings? I don't know if you can do that with cuttings or whether it's better to take rootstock. I've never worked with replanting aspen. I do know it's easier vegetatively than with seed but you probably have to talk to somebody who's worked with that. Okay, the question I have is we've seen a lot of cottonwood stands particularly that are just the older degenerate trees and there's no juvenile recruitment underneath primarily due to grazing. Will they reach a point where due to the heavy overstory of the older trees, even if they're given a rest, you will not get the juvenile recruitment back because they will shade out their own young, so it's big. Well, it depends on where, if you have a say an alluvial bar that's shaded 100% by that cottonwood stand, I suppose that could happen but generally the places where you get new seedlings established are not underneath the shade of the old trees. The old trees tend to be up on terraces and not close enough to the stream and usually the valley's broad enough too that you're gonna get a lot of sunlight during the daytime. Does that answer your question or is it? Yes, but if you do protect that old stand, like you say, what I'm thinking of right now is up on a bench and it may be not the most desirable place for juvenile recruitment but can you get regeneration under that old stand by protecting it or should you try going somewhere else and reestablishing a stand somewhere else? I would say it would be better to go somewhere else, you wanna go to a site. Dr. Heilman I'm sure will talk about the germination of seeds and the growth of vegetative material that gets rooted but it needs moisture when it's first getting established and generally the older trees aren't a site that doesn't have a lot of surface moisture. I don't think they're really appropriate sites for a generation of new seedlings. What I'm having a couple with is kind of dying out. I don't know enough about plants that seems that it's probably bugs that leaves just turn brown and often it'll start, a new one will come up from under the ground the next year but I'm wondering whether there is something that you might suggest that I spray it with or anything like that to encourage them. Yeah. Actually I couldn't tell you I'm really not very knowledgeable. We'll be covering that subject with Wayne Shepherd on regeneration and disease so come back. Cologne type tree, what about planting young trees from different sources fairly close to one another? Is that a bad idea or? I don't think that's a problem. I think that the colognes can intermix. I don't think you'll have any suppression of one tree over another. Any more questions from the local audience? Okay, I don't know if the audio bridges are up but let's go to the remote sites and if anybody's got questions out there, ask them. That was an excellent example using land survey information and the recent aerial photo. Have we got many examples like that? It seems like an excellent tool for your subject that you're working on in terms of historic variation or was that just luck then? Actually it was really just luck. In fact I looked at land office survey records for a whole bunch of areas. The land office essentially is now what's, is the BLM, the Bureau of Land Management. I went to the Baker area office and looked through their survey records at several valleys throughout this part of Oregon that I know now have cottonwood just to see what the extent might have been but most of the surveyors unfortunately did not draw a nice little map showing the extent of the stand. So you can read through the section line descriptions and they'll say yes I'm walking through a cottonwood gallery but they won't say how much there is. You know, is it 20 trees wide or two trees wide? Unfortunately. What are the earliest aerial photos we have of the Blue Mountains and have you tried any analysis back and forth with aerial photos within the period of time that we've had them? Unfortunately I can't answer either question. I'm not sure what the earliest aerial photos are and I haven't looked at them yet or done any comparison. I think it would be a great project. It would be very time consuming. If you have any people who are really excited about it. Elizabeth, some of that work was done on the Middle Fork John Day on the Nature Conservancy preserved by Karen Welcher and Catherine Grant and they found aerial photos from 1939. They compared photos from each decade from the thirties to 1992 to look at the change in the tree canopy. So there is some. Are those photos, the 39 photos just local for the Middle Fork or are they, do you know how much area they covered? I don't know the extent of them. We found the 1939 at the University of Oregon Aerial Photography Museum or Lab. I'm sure a lot of things exist. It's a matter of digging them up. Okay, all of our remote sites are up. So if you've got questions out there, be sure and ask them. I had a question from John Day. Go ahead. Can you give us some indicators that we can use up bigger for, well, Aspen clone that we can use to determine whether it still can be regenerated? Well, I guess I don't have any specific indicators of vigor, but I imagine if you can still, I think as long as you have overstory trees that it's possible to regenerate that clone, once you've lost all the overstory trees, I don't know how long the rootstock will survive underground and still produce suckers. Well, you mean how dense is the canopy? Yeah, most of our Aspen clones will find it in with dense invasion of dug furs and pine, and the Aspen is pretty decadent. So how decadent can it be before we think we can get it back? I would say if you still have trees standing that you probably still have a viable clone. And at that point, if you want to cut down all the trees or burn them all out, you would probably still get suckering from the root clone. Thanks. Other questions? John Decker. Go ahead. Do you know anything about historical patterns of beaver populations growth decline and if that's had any influence on Aspen or Cottonwood? That's a good question. I imagine that's had a tremendous influence on Cottonwood and Aspen. It may be that beavers used to move vegetative material around that could have been re-rooted if it wasn't chewed to the point where it couldn't survive any longer. I really can't tell you what, I really don't know specifics about the influence of beaver on these populations. They can come in and cut down an entire clone and if the regeneration can't survive grazing or browsing, then the clone can be killed off and in which case the beavers started the death of that clone. Other than that, I really don't know. Thank you. Good questions here? Willie's got one, okay. Go ahead. Yes, Elizabeth. Although the Cottonwood was more typically a bottom stream species, is there any problem in trying to establish Aspen clones along those galleries to replace the Cottonwoods that used to be there? Or any preference with that? I don't see a problem. I mean, a lot of our Aspen stands do grow in bottoms. Maybe not necessarily right next to the stream where Cottonwood might become established. But I think you could certainly try and plant Aspen in the same areas. Whether it would be a replacement species is hard to say. I mean, they probably have different functions in the system itself, but I would think you could grow them in the same locations. I don't know how well Aspen will grow on a very coarse substrate. Most of the Aspen I've seen has been on fairly fine substrates, so that might be a little bit of a problem. Question from Baker. Go ahead. Would you hazard to guess what percentage of, let's say, the Wallaul Whitman, as far as at least your forested area, the Malheur or the Humatilla? Let's say, I know this is a hefty guess, but let's say a hundred years ago was, let's say, in, let's say, Aspen's like 10% of maybe the Wallaul Whitman. Let's say maybe 20% of Humatilla, 30% of Malheur. Do you have any feelings for that? At least looking at all the drainage that we have in those forested areas. That's a really good question, Matt. I don't really know the answer. I don't think I could hazard a guess. Unfortunately, I couldn't even tell you what the percentage is now. I know that some inventory efforts are underway on the districts, the National Forest Districts, and I think once those inventories are done, we might be able to make a guess at what the former extent of these stands was. But it'd be hard for me to even make a stab at it. Well, my experience has been at least on the marks of the Wallaul Whitman. I've driven from parts of the other forest is just about every drainage has one Aspen left in it. That is alive. And a lot of this, you know, due to concrete encroachment and, you know, some of those other things that you talked about is very long of water tables, over-browsing, trampling, things like that. But it looks like we have a lot of opportunity on the three-fourths if we so desire to bring back some diversity back into the forest. Yeah, I think we definitely have a lot of opportunity. That's an easier thing, I think, to talk about than what the exact past extent of the species was. It seems like Aspen can grow in an awful lot of places. And we don't even see it right now that much in grand fur areas. I think it's really been shaded out there. Most of the decadent stands you see here. Aspen appear in Pond or Supine and Douglas Fur, but I think it could have been quite extensive all the way up into our grand fur until perhaps it got too, well, I want to say too cold. That's probably not a good description, but to the elevation became too high for it. But yeah, I think we have an awful lot of potential. Question from Seneca. Go ahead. Hi, Elizabeth, do you know exactly, well, can you give us an idea of what the elevation ranges of the two species are? Yes, I think cottonwood elevational range is probably, well, it may be below 1,000 feet and up to 3,500 to 4,000 feet. That's where you get a self-perpetuating populations. It can grow up to probably 6,000 feet, literally physiologically grow, that is. Aspen, I'm not exactly sure what the elevation range is of Aspen, but I would guess somewhere from 1,000 to 2,000 feet up to about 6,000 feet. Other question? I have many members of the audience saying higher, higher. So. 8,000 feet. 8,000 feet, okay. 8,000 feet. Jim. I have a question about the silver culture. I've heard of a wide variety of people, a lot of foresters and woodlot managers, talk about how to encourage the faster growth of a young stand of Aspen, given the fact that that decadent stand that sort of started it is falling away. And I've heard thinning used as a, you know, as a speculated as a means to increase the speed of re-establishment of the stand. Do you know anything about whether that will work? I don't know specifically, but it sure sounds right. I mean, the stand is going to be thinning itself extensively throughout its growth anyway. And I would imagine that like other trees that if you thin them, that just allows more nutrients and water for the trees that are left over. So I'd have to agree with that based on my intuition, but I don't know specifically. If you're going to use a control verb sometimes to stimulate suckering in Aspen, what is the time of year to do that to get the maximum success? Oh boy. Well, I've read various papers on that and it seems that the results differ, but I think that a spring or summer burn produces the least amount of suckers and a fall burn produces the most amount. But that may vary based on the site. I would hate to say that's a hard and fast rule. Yeah. Are there questions? Are there any more? Push your button in. Just a moment, you're breaking up really badly. Can you get closer? Can you repeat the question? I couldn't hear you. We have Aspen sands that have nucleic lodge under us upon 20 to 30 inch diameter flowing throughout. Seems unlikely that these trees came in after the Aspen. Is there any particular amount of crown closure that inhibits the regeneration of Aspen? I don't know what the specific amount of crown closure is that inhibits the regeneration of Aspen. I'm sorry, I can't answer your question. Other questions? Table, how deep the water table should be in order to bother planting Aspen. I know I have a high water table in an area that I'd like to plant trees in. But I'm wondering, and the ones I've planted already, I've watered them a lot the first couple of years, just like carrying water. But I'm wondering how deep the root system goes and whether I'm wasting my time trying on that spot. Well, do you have a fluctuating water table or is it at the same height? I believe it is. The surface, I believe that the water table does fluctuate. The surface water certainly is there for part of the summer and then gone. But I'm thinking that under the soil, it's probably less fluctuating. So you think the water recedes from the surface, but it may not recede too far below the surface. I don't know how much free water the roots can withstand before they start to smother, to choke from the actual water. My concern is in the other direction. I'm wondering how. If there's not enough water? I can't answer that question specifically. Exactly, how much water do you need all year round? How deep? How? Yeah. To the water table? Right, I'm not sure. I mean, I've seen Aspen clones where the water table is greater than a meter. And I've seen Aspen sands where the water table is at the surface even in mid-summer, mid to late summer. And both types of stands have been thriving. But a meter? Yeah. It's the water table fluctuates though. I'm sure it's within a foot or two of the surface in late spring. Once the stand is established, it probably doesn't need as much water as it might be in the morning. Catherine? You've limited your comments to the species Tricocarpa. What about patterns of distribution and the occurrence of deltoides throughout the valleys and into some of the lower reaches? I haven't seen deltoides. So I assume that we probably didn't have any in the past. I don't know that for sure. And maybe Dr. Heilman could comment more on that distribution than I can. OK. I think we've just done it. OK. Go ahead. Any comments on how Aston and Cottonwood might answer this? So we're all diversity in the forest, in the forest, here in North Eastern Oregon. And possibly also your feelings and thoughts on what we might do to do as well as you mentioned. The outside, at this time of the year, when they're very shelling. Well, I could probably answer your second question first. Most people are going to notice these stands when they're along roads that go out for a drive and not necessarily want to get out and hike for miles. So if we wanted to enhance enjoyment of these species, I imagine we'd want to work on stands that are closer to roads or areas that people tend to visit quite a lot. And we have quite a few roads in the Blue Mountains. And a lot of them are long streams or waterways. And so it wouldn't be too difficult to find heavily traveled roads, popular roads for people to go on in the fall, especially where there might be other hardwoods that show nice colors in the fall. If we drive around right now, you can see an awful lot of hardwood shrubs that are turning red and will look beautiful with golden aspen or cottonwood next to them. My thoughts on how these species provide diversity to the forest is definitely important to have some hardwoods in our forest. They perform different ecological functions than the conifers. The leaf litter from hardwoods provides different nutrients to the soil than hardwoods. And they certainly provide different habitats. We know that if you spend any time in aspen stands, you'll see quite a lot of woodpeckers and sap suckers. The wood's softer. And those trees are very susceptible to fungal infections. And so they tend to rot and are easier for the birds to peck holes into and nest in. So I think they provide very important nesting habitat. And also elk and deer and cattle really enjoy hanging out or spending time in aspen stands and cottonwood stands. They like to eat the young suckers. As I said, it'd be nice if they wouldn't eat quite so many of them. But they do like to eat the young ones. And well, that's my feelings on the diversity of these species. Do we have any other really good questions? It seems to me that people's awareness of the importance of cottonwood in aspen has been very recent. So has there been more interest in the past, or is it just recent? And is there good publications that you could refer us to about them? I don't have a publication list with me. I could probably find some for you personally if you wanted to talk to me after the talk. There's been a lot of concern about aspen in the West. I don't know about the Blue Mountains in particular, but you can read publications that are at least 20 years old talking about the decline of aspen in different parts of the West, especially where it has a greater extent or had a greater extent than here. So that interest has been there for a while. I don't know how much interest there is in cottonwood or has been in cottonwood. But in the Blue Mountains, it would be hard for me to say there is an aspen committee in the Blue Mountains that might be able to comment more on that interest and how long it's been around. This has to be very gratifying for me. I've worked on a very unpopular group of species for something like 26 years in a region that is so overwhelmingly conifer that any forester in their right mind that would work on something like cottonwood was not in his right mind, obviously. We've fought battles, not battles, but I've taken my share of abuse for working with these species. Much of the information I'm going to give today has come from the work we've done in high-yielding plantations. But it is appropriate for some of the work tells us a lot about how important cottonwoods are in a riparian system, what their functions are, how valuable they are. Their contributions are very great. And the species I want to talk about are the riparian species of narrow leaf cottonwood, populous angustifolia, populous balsamifera. Now that's the northern cottonwood, north of here, Canada, and so on, populous deltoides. That's eastern cottonwood. When we first started working with this cottonwood, we had no idea that we had populous deltoides populations right here in Oregon and Washington. And they're found in the hot region of the Columbia River, Umatilla. They're big stands of populous deltoides. Populous Fremontii, a southwest species, extremely important in riparian systems in that area. And finally, populous tricocarpa, which is the, you have it here. We have it on the coast. It has a huge range. It runs from Southern California to Alaska and the coast to, well, virtually the continental divide. Much of the work we've done has been with hybrids between populous deltoides and populous tricocarpa. People who work in wild lands have not identified much with that kind of a plant, a hybrid. But lo and behold, we have natural hybrids right here in Oregon of populous deltoides, populous tricocarpa. Where these populations of deltoides are in the hot regions of the Columbia and the John Bay, you'll find these species there. At the upper reaches of the tributaries that enter their Columbia in these regions, you'll find the tricocarpa. And in between, lo and behold, hybrids, natural, turns out hybrids are very common in a natural of poplars or on cottonwoods, are very common. They exist wherever these species happen to overlap, the ranges happen to overlap. And they're extremely important areas for the kinds of special animals, insects, and so on that are associated with those hybrid zones. Not only are the cottonwoods themselves a special habitat for wildlife, the hybrid zones are even more special. So all of these species are what we'd call pioneering species. Foresters would call them weed species. They produce abundant seed. And this is the seed that comes with cotton attached. It's typical of all the Salakaceae that's poplars and willows. The trees in this group are all dioecious. That means they're either male or female. This is a very important consideration when you're looking at a few remnant trees in a watershed is what they could all be male trees. And in some cases, the reason you're not getting seed is because males by themselves don't produce seed. These seed then are extremely rapid in germination. They'll germinate overnight. You plant them today, and they've germinated tomorrow. The root growth is fairly rapid. They have to get this root down. It's a small seedling. And that seedling extension downward has been measured at about a half a centimeter a day. So they're following the drop in the water table on some of these dry bars where the substrate will allow the roots to penetrate. The seedlings are also terribly, terrible competitors. They can't stand shade. They can't stand grass, weeds. And so they have to have a special open seedbed, new land. They also grow very rapidly to tree size, which makes them extremely important in a riparian system. The flood came through, wiped out the vegetation, put out some new seed. In a few short years, we've got a plantation back, which is extremely important in alluvial system. Now, what do these trees do in the way of growth and production? Production of biomass, it beats all of the trees we have here in the Northwest. In fact, cottonwoods are probably the most productive tree in the temperate region of the world. Clearly they are. For timber purposes, the James River farm down on the lower Columbia has an average of about five dry tons of clean chips per acre per year produced in their plantations. This means that total biomass, not including roots, is upwards of 12 to 15 tons per acre per year. I'll show you some figures on that later. Root systems, I always talked about the rate of growth of these root systems from seedlings. The root length density, now that's a measure of how dense the roots are in the soil. And the index is how many centimeters of root are contained within a cubic centimeter of soil. And in the studies we did, the average density in the top 18 inches of soil, 18 centimeters rather, was six centimeters per cubic centimeter. In other words, they went back and forth through that cubic centimeter six times. The total length of fine roots, now these are fine roots. They're as fine as hair, the finest. The tree doesn't invest a lot of carbon in its root system, but it produces, it puts out an amazingly proliferating system. We measured the length of roots in a hectare, that's 2.47 acres. And it was 300,000 kilometers of roots. That's on the order of grass. They know how thick grass roots are. So they have, this is a very important aspect of these trees in the way they can stabilize soil and so on. The root depth distribution, if they have the soil, I'll show this graph here, on this side we have meters of depth below the surface and fine root density centimeters per cubic centimeter. Over here at six, up here these five clones all had an average of six centimeters per cubic centimeter. This drops off rapidly with depth, but even here at three meters below the soil, that's over 10 feet, there's substantial rooting. And when we dug this, 10 feet is as deep as we went and there were still roots heading downward. So this was in alluvial soil. So they are capable of serving, pursuing water at a very great depth. The other thing we noticed in alluvial systems, they would not proliferate in sand. They go straight through sand. They come to a silt layer, organic layer, and they totally occupy it. So they're very opportunistic. They're just, it's an amazingly functional system that they have. Now, in terms of biomass, and I can show you some data later, combining the stumps and fine roots, you get about 35% to 42% of the biomass of the above-ground tree in the below-ground system. And the way it differs from most of our conifers, these roots are extremely light. They're not dense at all. Have you ever picked up a cottonwood root? It is so light. They do not commit much carbon to their root system. And this very fine root system that I was talking about, hair-sized roots, means they're getting, for the amount of carbon they expend on their root system, they're getting a tremendous access to soil. Now, here's some data on yield in megagrams. That's also a metric ton per hectare per year. Black cottonwood is listed first. Low yielding, high yielding black cottonwood. Woody biomass production, this is above-ground only, 7 to 18 tons per hectare per year over the first four years. That's including the first year when they don't produce much. The t times d hybrids in this study, only two clones here, 27 to 28. You can see what an advantage we're getting in growth out of these hybrids. And then here's a conventional old hybrid from Europe, nigra, deltoids times nigra, and it's certainly on the order of black cottonwood. The annual leaf fall, this next topic, you can see here we're getting from four to almost seven tons of leaves per hectare per year. And that leaf fall with a concentration about 1.4% in, as it falls, is contributing up to 80 pounds of in back to the system, back to the soil. These trees, two points here that I think of. First of all, the concentration in the leaf fall, 1.4% on the average, and there's some variation, that corresponds to three or four when the leaf is green and live. So the tree pulls most of the nitrogen back out of the leaf before it drops it. Very effective system, and it contrasts totally to red alder or any alder, which having, being a fixer of nitrogen, has no economy to conserve nitrogen. So it does not withdraw nitrogen from its leaves to any great extent. It drops them as if it, who needs it? It'll make some more. So you'll get much more, much higher concentration of nitrogen and alder litter than in this. And we're going to talk about that later. In terms of the total nitrogen in litter fall recycled back to the soil, that corresponds to about 200 pounds total uptake of nitrogen by the crop. So it's taking up 200 per year and dropping 80. Even as conserving as it is of nitrogen, it's still cycling a lot of nitrogen, and maybe almost as much as alder does. Here's another table. The only thing I want to show on this is the small and fine roots. This particular clone has, at a four-year-old tree, 11 metric tons per hectare of fine roots. Those are roots less than half a millimeter down to hair size. So you can see populous tricocarpita is not shabby in this regard. And neither is populous deltoides. They're all, all of these species have this very effective and proliferating root system. So what is the net effect of all this on the stream system? We're talking about riparian species, high in uptake. I'm including willows here, high in nutrient uptake, and high in cycling nutrient. Well, the first thing that we can capture and take advantage of is the use of poplars or willows along the streams to buffer the stream from agriculture. And animal feeding, any use of fertilizer, the depth of the root system of the poplars and their ability to forage nitrate, which would be the form of moving nitrogen, is unsurpassed. So they can provide a very great function used as buffers against nutrient movement into streams. The second thing about them is they put their roots out into the stream. How many of you have seen cottonwood roots in the stream? Well, what's that doing? I mean, it's pulling nutrients out of the stream and putting it on land. What could be better? Admittedly, the litter comes back, but it's not coming back to the extent that it's being withdrawn. So it's an amazing system here to do what we want to do in improving our streams. In comparison with alder, I told you about the nutrient content of the alder, litter versus cottonwood, it's very different. When you put alder litter in a stream, you're putting lots more nitrogen. Now, these two trees, cottonwoods and alders, interact in some very interesting ways. First of all, the cottonwood overtops alder. As fast as alder grows, it overtops it. Now, that's not surprising when you're talking shrub alder, but when you're talking red alder, which overtops everything that grows with it, all the conifers on the west side that grow with alder get overtop by it. If you put it with cottonwood, cottonwood overtops it eventually. And what happens when you overtop alder? Well, we did this study several years ago where we mixed cottonwood and alder. And, OK, zoom out. OK, excuse me. We've got three different alder crown classes. These are all planted with cottonwood on a one-to-one mix. Every other tree is cottonwood. Every other tree is alder. Where the cottonwood clone was not a fast-growing clone, and we had some in this. They did not overtop the alder. We only had one tree in this class. Its mean height was 6.2 meters at three years. Now, I'm not sure whether it's three or four. DbH, 5.7 centimeters. 13 grams of nodules. And a settling reduction rate, which corresponds to nitrogen fixation rate, was 79 micro moles per gram per hour for total nitrogen fixation of that tree of 1,006 micro moles of nitrogen per tree per hour during the daytime. Where it was a co-dominant, the tree's even somewhat larger, because of the shading from the cottonwood, that drops down from 79 micro moles to 20 and only 267 micro moles per tree per hour. Now, where that it was intermediate, it isn't suppressed, but it is overtopped by the cottonwood. It's 5.6. Now, it's a smaller tree. It isn't too much smaller, a little shorter. Micro, acetylene fixation, 5, and trees per moles per hour, 28. So from an overtopped alder to one that's full blown out in the open, we've got, what is it? Almost 50-fold difference in nitrogen fixation. And what does that mean to us? It means we've put a damper on this nitrogen fixation. This tree, this alder, which we see throughout our region, covering our streams, dumping nitrogen in, then these streams flow out into the agriculture, pick up more nitrogen. The algae load gets tremendous. We've got this alder that's pumping nitrogen into it. We can put cottonwood in there, overtop it, and slow that thing down. Now, what about the effect of alders on cottonwoods? I've got some interesting slides. I hope I have time. Probably don't. Right here, effect of alders on cottonwoods. Of course, they supply the cottonwoods with nitrogen. And this is important in pristine deposits where there's no organic matter. Cottonwoods don't get a lot of nitrogen out of systems like that. But alders acidify the soil. The production of ammonia by alder and the litter gets nitrified to nitrate and gives up on hydrogen ion. And in Alaska, a study there of Sitka alder, it's not unlike Alnist and Conna, we can see that the pH here under alder, subalpine alder, is brought down to 3.8. While there isn't a cottonwood that will grow at pH 3.8. So alders can eliminate cottonwoods by the acidifying effect they can have on the soil. So you can see here these different sites, alder, subalpine, alder, below timberline, almost as low, 4 mixed woods, 5. The bases in mixed woods, birches, spruces, and so on, counteracting some of the acidity generated by nitrification. So earlier, we had a question on beavers. Now the thing that is particularly appealing to me about what I'm doing right here is not only technology, it's wonderful. I mean, it scared me to death at first. But geez, it's really terrific. And the second thing is the sad state of our streams in the West. They are an incredibly deteriorated state. 85% I've heard are degraded from one cause or another. Dam building, water extraction, channelization, all the things that Elizabeth talked about. It's a disgrace, really, what the conditions of our streams are in. And one of the reasons for it, according to people who have studied it, and I'm not in a position to doubt them, is because of the loss of beavers. Before man came, there were more than 60 million beavers in North America, population. Trapping brought them close to extinction by 1900. Can you imagine that? 1900. Today, there are 6 to 12 million. Beaver, by building dams, felling trees, has an enormous effect on riparian systems, on stream systems. It's incredible. I was fishing in BC in a high plateau, and all of the lakes there were supported by beaver dams, every one of them. Without those, there wouldn't even been lakes. So this loss of beavers and their dams has led to sedimentation of streams, downcutting of channels. You lose those beaver dams, and pretty soon, you got a sluice way. And elimination of riparian deciduous riparian forests. The reason for that, the lowering of the water table, downcutting, and the water table's gone. It was up here in this valley, and now it's lowered to the extent that cottonwoods or aspens can't handle it anymore. Low summer flows. Without the beaver dams, the stream system is much more flashy. You don't get the slow release in the summertime, and you get drought injury to these species. One of the most interesting things to me is this one, the loss of seed beds associated with the periodic destruction of beaver dams. Now, how can it be that an animal that cuts down trees can benefit trees? Well, cottonwoods need this clear seed bed without vegetation. When a beaver dam breaks, for whatever reason, flash or whatever, there's a seed bed that is amazingly receptive to cottonwood. So if there's a few that they haven't cut down, suddenly there's lots of them coming up. And this I am convinced is what got our population of these trees so high when beavers were here. And talk about what's Dwayne Eckert. He was telling me he took a float trip on one of the forks of the John Day. 80 miles, he found eight trees. And the historic photos that you were talking about showed extensive stands in these same areas. OK. Now, there's the rub right here. With intensive grazing by livestock and other animals, restoration of poppers and willows to levels required to support beavers may be impossible. It is a huge task that faces us. There are some neat tricks, though. Use of mega-cuttings hammered in with equipment, other things. I expect somebody will be talking about restoration later. So what is, when it comes down to it, what is the importance of large trees to riparian systems? First of all is the shading they provide for the stream. Extremely important for fish, salmon, trout. They reduce the flood velocity. These trees are a barrier to stream flow. I couldn't find a picture of the St. Mount St. Helens flood mud flow that came down the Toodle River into the cowlets. And there's mud marks on these cottonwood trees that are still standing that's 12 feet high. This mud moved into the stand, and the stand stayed there. Now, the mud moved on, but it certainly, if we can do that with a mud flow and slow it down, it could do that with a flood. Of course, they stabilize the alluvial surface because of it. Slowing down the water, you don't get the erosion of the alluvial surface. And you get, in fact, deposition. So you get a buildup of set of it, a buildup of these valley floors, which are so important to us. And then roots, of course, the root system, of course, stabilizes the stream bank. The root balls, root masses, really put a barrier to erosion. Of course, sometimes their trees are undermined and the tree falls down. And then we have woody debris in the stream, which we all know now is something we like. By decreasing the velocity of a stream, it decreases the sediment loading of the stream. The sediment load corresponds to the velocity of the stream. And by decreasing the sediment load, you decrease the scouring ability of the stream. The high sediment stream can virtually float boulders. Mud flow, the boulders float. And so you get much more damage in a scouring effect when you have very high sediment loads already present. It just feeds itself. Of course, roots increase the irregularity and diversity of the bank, overhangs, pre-gaining habitat for fish, refuge for fish against mergansers, and so on. It really is important, the pictures that Elizabeth showed of those channels of streams where there was nothing, no cover of any kind. You can go to a place where the cottonwoods are in the stream the way they should be, and those banks where they're undercut root systems. There's diversity. There's habitat, a great entirely different kind of stream system. And of course, the cottonwoods can shade out the alder. The seedlings that Elizabeth showed on the river bars initiate forest succession. Trees, the cottonwoods grow up. And the more shade tolerant conifers come in below. And then of course, we have perching, nesting sites. Elizabeth talked about lots of wildlife uses. And terrestrial insects, which again, form part of the food chain in a stream system. So with that, I will open it to questions. Oh, I have some slides. We can run through those quickly. I want to show you what a four-year-old plantation of hybrid poplar looks like. Look at the density of this. These trees are 10 feet apart in rows, 7 feet apart down the row. These might be 5 feet. The leaf area index here can be as high as 10. I don't know if you know what that means. In other words, there's 10 times as much leaf area in the crown as the crown projects on the soil surface. This is a huge leaf area index. It's bigger than most of our conifers. We're talking 3 to 4 in the conifer. Let's see. This is what I'm talking about. Root systems. Here's roots from a cutting dug down. These are, this cutting was planted in April. This was dug in mid-August. It's 1.4 meters to the tip of this root. Going down, it's 2.4 meters to the end of this horizontal root. That's within a matter of months. The litter fall, here's the litter just after it's fallen. Remember, I'm saying about 4 to 6 tons per hectare per year, per hectare right there, the next May. Any of you know what these little dots are? Nightcrawlers. This litter supports so much activity in the soil. It's gone by May on the West Coast. Here's a little study we did on the Mount St. Helens mud flow. You can see the level of mud along the far bank there. It's washed away because that's where the river is. We planted cottonwood cuttings on this almost sterile ash material, unbeknownst to us. It had already been seeded in by alder. Little seedlings here. The cottonwoods are carrying the nutrients that they brought to the site. So they're nice and green. They're just flushing out, just starting to grow. Here's the first year. The alders have gone this high. The cottonwoods are struggling. They don't get any nitrogen out of this. They're overtopped by the alders. In this sterile environment where alder, with its nitrogen fixation, can get a jump on them. And this is what it looks like, this stuff. It's ash from the mountain. Some of the cottonwoods never did make it. Here's one that suppressed after about two years, three years. But many of the cottonwoods did make it. And they are already getting above the alders. You can see across the river here. And this is what eventually will be the case. Here's the alders. This happens to be red alder. Here are the cottonwoods. Now this has been logged back here, so they don't have a full stand to show much overshading of alder. But that's a general idea of what I'm talking about. And this is a, I don't know if it's typical, a so-called down cut stream from this area. The valley floor is up at this level. Formerly the water table was somewhere higher than it is now. You can see how robbed the valley floor is of its former water table. And again, ongoing erosion, down cutting taking place in a stream in Oregon. So that's the end of the slides. OK, now I think we better see if the audio bridges are up at the remote sites before we have questions from this audience because they're going to shut down pretty soon. So can you still hear us at the remote sites? And do you have questions? Nobody's there. They may already be shut down. I know we only had about 48 minutes, so. Oh, I have a question from Baker before Dr. Heizer. Go ahead. A lot of what answers when you look at viparion improvement projects are against you. They transpire so much. Well, they transpire about as much as Douglas Ferd does. I don't know how much more they transpire than a stand of conifers that you'd have here on the east side. My feeling is that that's, of course, a important issue. But the benefits, in fact, do outweigh the derogatory effects. It's interesting that in South America or South Africa, you have to get a permit to plant a tree on a riparian system because of water use. Fortunately, we don't have that situation here. Any other questions? Take one from this audience. Yeah, I have a question. I have a question. Before you start, just push your button down once, Paul, and then let go. Go ahead. My question, I have actually two questions. The first one is related to private landowners of my home, cottonwood, and all would be yours. I can make a blanket statement, but what are some of the things I guess they could look at in terms of a super cultural system for practices that they might use to manage those stands or whatever objective they might have with running through timber, wildlife, and so many other benefits we talked about. How can we end those stands and do some harvesting if that's an objective but still maintain the benefits? How can we do that for the cultural? Well, I think you can do it in block cutting, partial cutting. As long as you are not replacing the cottonwoods, you have some way to keep any plantings or sprouts coming back and replacing the older trees. The older trees do have a limited life. Most of them that I've seen in this region are really decadent, so there's not a lot of timber value in the old trees. But it's certainly possible to establish for a landowner to do what's being done in the basin, and that is have an active program of establishing rows of trees along their stream beds and then count on periodic harvest. And surely if it's done so that the period of no vegetation is limited, it's going to be beneficial. Now, you can do coppicing. That's one way, but we don't advocate coppicing in production systems. Explain coppicing. Coppicing is allowing the tree to resprout and the sprouts then from the stump to become the crop trees. This works very well up to a point. When the stump gets too big, the sprout can't engulf the stump. It's sitting on the side. The stump rots away, and you've got a non-wind firm tree with a pencil for decay. Managed stands of black cottonwood. I don't know of any yield tables. In fact, we don't have them for hybrids. But you're going to have substantially less yield with tricocarpa than the lower numbers that I saw and probably the low end that we saw there on that table. What you're asking in a way is what are the opportunities for more extensive management, traditional forest management of cottonwood? And there's one company in British Columbia that has whole operation is that. And they are producing cottonwood for pulp on a 15-year rotation. In the Fraser River Valley and some of the other river valleys in BC, they do use some planting, but it's clear cutting and immediate replanting. Using cats to push cuttings down into the soil, they'll resprout and become trees, the branches. So one can operate in cottonwood on a low input level and be fairly rewarding, I think, long as we have these high pulp prices. Let's go to the remote sites again for a moment and see if anybody else has got questions there. Anybody have a question from Burns? OK. Yes, we have very few cottonwoods left on some of our stream systems. And I'm not really noticing any cotton or seed being produced. I'm wondering if male cottonwood trees are longer lived than females. We've noticed the same thing. It's disproportionate to males in droughty environments. And I don't know why, but they seem to be the ones that are the last of the species. So I don't know. Artificial seeding is, of course, out. I think you can take advantage of cuttings and bring cuttings in from either wild plants or just from your own trees that are there. Of course, if you want to get an even sex ratio, you have to make sure that you do that on your cuttings so that the future generation has a fair representation of both. OK, other questions from remote sites? Female cottonwood trees and low elevation. And I think there's a professor at the University of Washington who specializes in populous or at least cottonwood that has said that, but are you familiar with that? Can you explain that? Well, I've worked all my career in cottonwood with Dr. Stetler. I've never heard him say that, but he's said a lot of things that I don't know about. I think what I've heard him say is plant trichocarp a higher elevation in the stream systems. Maybe hybrids, intermediate elevations, and deltoidies at the lower elevations. Could that have been what he said? The L.M.E. side shipping our cuttings over the west side. And I was only part of that as far as one of our foresters went to one of the meetings. And I think he was talking male, female, understanding that he couldn't explain it. That's why I guess I'm asking the question. Not exactly. OK, we'll go on to another site or another question. OK, we have one here at the La Grande site. Along the lines of the last two questions, is there a way when you're out in the field you can tell the difference between the two sexes? The only way you can tell is to look for dropped catkins, especially early in the growing season. If they had catkins and they dropped them, you can find them in the branches. The males are dropped quite early, even before leafing out. The female are dropped later because they stick on for another month and then they fall. So you can see the cotton. The cotton is present in the capsules of the female catkin. The other way you can take, in the dormant season, you can examine the buds of the trees. And if you know what you're looking for, you can tell in the bud the difference between a male and a female flower. Other questions from remote sites? We've only got a couple of minutes left, so hurry along with your questions. Any more here from LeGrand? Yeah, we got one here. OK. Press the red button. Just press it down once. Yes, I would suggest that perhaps you're just talking about trans evaporation from the cotton woods, that maybe the cotton wood shades the stream and therefore prevents evaporation by the heat of the sunshine. And maybe it offsets that, plus making the water cool. Yeah, it perhaps does to some degree, sure. I hate to do this, cut off questions. When we've got so many good ones, we better break and thank Paul.