 My name is Hans Skandel. I'm an extension agronomist at NDSU. North Dakota farmers have been growing traditionally a lot of spring wheat. At the end of the season in August or beginning of September many of the growers decide to work the fields because we don't know what the conditions will be in the following year and black soil tends to warm up faster than when there is a stubble. In the past horses were used to work the ground, to work the weed stubble. Nowadays of course we have big equipment and traditionally it can be blackened very quickly. In this particular field we have worked the ground substantially. However we would prefer to think about more a live cover and increasing the soil capacity, the soil health. So today we're going to talk about cover crops after wheat. Instead of having black ground we want to mimic nature more and in this particular example we have had the spring wheat harvested. Some of the seeds came out of the combine and we have here a situation of volunteer spring wheat. As you can see we have a green cover. This is an experimental site and previously I had spring wheat on small plots but I had also alleyways where we did not have any crop. And we can see the color difference in these two areas where I'm standing it is fairly light green where the alleys were we see a dark green because there is more nitrogen. So the plant can take up some of the nitrogen that is still in the soil and capture it instead of having some of that nitrogen leaching away. A live crop is very important for soil health because we have a living root system we have the crop growing and it is now able to add some more organic matter. Also for soil erosion control this field will have very limited soil erosion compared to a black soil. Today we're talking about cover crops. We saw that we can have a crop growing just as the volunteer spring wheat but in this case we also planted some different cover crops into the stubble. We used a planter that was able to plant right into the stubble and we chose a number of different legumes as well as broadleaf crops. We are looking here at a legume because legumes tend to be able to fix some extra nitrogen. Field pea is one of the legumes that has a great ability to fix biologically nitrogen. So in the particular plot that we are looking at here we see the legume the pea also surrounded by the volunteer spring wheat. So here we make use of the natural residual seed that came out of the combine for the wheat and we just planted in this case field peas. Another group of plants that we are testing are the brassicas. Brassicas have the tendency to grow really well into the late season the cool season crops and we have here some radishes. The radishes again here are planted into the stubble of the wheat and we see a mixture of radish and the spring wheat. This is about a month after planting. Radishes in this case have the ability to make a deep tap root and loosen the ground and just for just a month growth we already see a nice little tap root starting to develop. We still have some time on the clock and this root will only grow bigger so before the season really ends this plant will still be maybe twice as big as it is now. Brassicas can grow late into the season but there are two types of brassicas those that can survive the winter and those that cannot. Here is one of the types that can survive the winter which is winter camalina. In this case we planted the winter camalina into the wheat stubble and we see a combination of the spring wheat and the camalina. In this case the camalina is relatively small but it will survive the winter and will start to regrow. All the small grain is spring wheat and will die off so we will have a cover next spring. The plants are relatively small at this time and they stay what we call in the rosette stage. Another cool season brassica is canola. Canola can also grow late into the season. This particular canola is a roundup ready canola. The reason why I selected roundup ready is that would give you an option to spray this field and eliminate the spring wheat if you desire to do so but I was also interested in seeing the competition between the canola and the spring wheat and you can see where the canola is growing it grows nicely and it is developing still late into the season and it will continue growing till we get a frost but it will not survive the winter. In this plot we see that cowpea. Cowpea is a legume but it is also a warm season crop. It typically is seeded if you plant early in the summer but there is a big risk if you plant late into the fall. This year we had an early frost in the first week of September and the cowpea which is very sensitive to cold temperature froze so it is not recommended to use a warm season crop in your mixture when you plant at the end of the season. Another legume we tried is the warm season crop soybean. Soybean also is not very suitable in cool conditions. With the frost the plants nearly died all of them but a few remained and tried to struggle to life but it will not amount too much. Therefore we should not grow the warm season soybeans into this system planting it late in the fall. A common winter annual is winter rye. In this case we planted the winter rye and we have the volunteer spring wheat. The winter rye is established right now and it will survive the winter whereas the winter wheat will die so next spring the rye will continue its growth and will cover the ground throughout the season. So in this case we have a mixture of two grasses the spring wheat and the rye. We have looked at several of the cover crops how they grow in the fall. Some of those over winter and now we are looking at the second year looking at growing soybeans on top of the cover crops. So in the area where we are standing we had cover crops as I showed you previously. In this region we planted the soybeans on top of some of the residue but also in some of the live cover the camalina and the rye and we planted some spring oats. The objective of this part is to see what is the effect of the cover crop from one year to the next crop the soybeans in the second year. So we have seen where soybeans are grown into a standing cover crop the rye or the camalina. In this case I want to show you how you can use a cover crop at the end of the season. Behind me is a plot of soybeans and in those soybeans in the rows as soon as the lower leaves of the soybean starts to turn yellow we can put in some rye or camalina and the rye or the camalina can grow in the canopy and then once the soybeans are harvested there is ample light for the rye to continue growing late into the season and it will survive through the winter and now we have a cover in the winter and it will start growing into the spring and we can grow another crop into either the rye or the camalina. In summary cover crops can be utilized in the fall, go into the winter and cover the soil. We can have some growth in the spring depending on the species. The benefits are to cover the ground to take up some residual nitrogen and in certain cases add some extra nitrogen if we use a legume. Do not use the warm season crops into the late fall but warm season can be used early in the season, in June, July, August. There are many options for cover crops and it depends on your intent of the cover crop which pieces you should select. In the second half of this presentation I'm going to talk a little bit more about the opportunities and about some of the research findings. First of all I'm talking about the opportunities. On this graph we see the hours of day length in Fargo, North Dakota. On the bottom we have the months of the year. On the right you see the hour of the day starting from 1 a.m. in the morning all the way to 11 o'clock at night and for instance in the middle of the summer the longest day this is the yellow is the day length available for the plants with on the top some dusk and on the bottom some dawn so this is the amount of sunlight in mid-summer. So if we are thinking about a normal crop production system we start planting like say the small grain probably somewhere end of April, beginning of May and then hopefully we can harvest the small grain somewhere in August. Now the graph here of course shows a little bit of a funny break on the left and the right that has to do with the day length saving time so we're concentrating really on the yellow part in this graph. So in August we harvest our small grains roughly and then we have a period that is frost free so the end of the growing season is maybe taking place somewhere in October so in that period after the small grain or even after canola or field pea we have an opportunity to grow a cover crop. After the frost we typically see that the plants are going dormant so during the last part of the season into November December we have a dormant crop and then when we look at the spring coming up we have first dormant in the winter and then maybe by March of April when the temperatures warm up enough it breaks dormancy if it is a winter annual and the crop starts to regrow of course all the annuals will have died during the winter but then when we are looking at March when the temperature starts to rise the dormancy is broken we have some additional growth of the cover crop so that's the second opportunity so we typically have a time in the fall and a time in the spring that we can utilize some of the sunlight and then probably somewhere in May we start to grow the main crop again after the cover crops that can be maybe soybeans so this is kind of the two main opportunities that I'm going to talk about today so we talked about cover crops we have already encountered several of them but basically what is important to know is that we are trying to establish the main reasons why we go with cover crop and mostly that could be presenting erosion or it could be improving the soil it could also to try to enhance the crop productivity long term that is what we are aiming at to add more biological life to add more nutrition to the soil that is recycled and therefore cover crops have many opportunities long term so here's a picture which I took after intercropping into sunflower so although there is also opportunities for cover crops in other sections of the cropping system I'm going to focus today basically on spring wheat or anyway wheat followed by cover crops as well as planting cover crops into standing soybean so as an ideal cover crop we really need to look at inexpensive sea it shouldn't cost us too much it should be easy to establish and then of course we need to have a plant that rapidly grows and that we can have a cover quickly in the fall low maintenance should be easy to kill so for instance most of the annuals winter kill so that would be an easy way to to kill the crop and it should not interfere with the following crop so the challenge really is where do we fit it in and I've already kind of indicated that for the crops that are grown early in the season small grains canola field pea we have this opportunity after the main crop so basically we need to find a system that is adapted to your area and we should kind of balance those short-term economics with the long-term benefits that we have to have some expenditure buying seed planting the cover crop but the long-term benefits are into additional carbon and crop protection soil erosion protection and therefore we are looking at it is a system now I've been showing you some video of cover crops in the eastern part of the state but I just wanted to make sure that this system can also work in some of the western part of the state in this case seeding took place when the hardgrass spring wheat was heading out and some of the seed was broadcast over the top of the growing crop the next picture is a system where it was planted after the harvest so typically farmers can use the cover crops as I mentioned for various purposes and one of the purposes could be grazing and again this is a picture from western north Dakota to indicate that it is possible however any system needs to have moisture available for the crop termination I want to talk a little bit about some of the tools that I've been using I use my cell phone with an app called Canopeo and that Canopeo is a system to kind of estimate the cover the ground cover of various crops it can be cover crops can be also regular field crops that we use now on the left picture you see a small grain crop and you see there is green matter growing there but in between you see also some soil and other particles so what this Canopeo does it translate every green pixel into white and everything else into black and then it counts all those pixels and makes a ratio how many pixels are green and how many are not green so that you get a percent so in this case in this picture as well 37% of that picture is green cover now I'm using it just kind of to give an idea of how much cover we have in our plots so I'm gonna explain a little bit of some of the results that we have seen of the video that you saw in the beginning of this presentation now I've taken these numbers on the 30th of September and the reason was that you know on average long term our frosts is taking place somewhere at the end of September beginning of October so I'm just trying to give you a realistic number of what you can get now in this particular year the growth extended after the first frost early September but the growing season continued all the way in October so so I could also have gone into October and given you higher numbers but this is just a snapshot of what is potential for cover crops so this was planted after spring weed canola soybeans pea etc as I showed in the in the video now in this case we look here at the at the number 89 percent of the field was covered by the canola the soybean plots at 52 percent now I showed you in the video that the soybean plants warm season crop and also the cow pea warm season crop died when we had a frost taking place in the beginning of September that is why it is not advisable however in the system that I utilized here is the volunteer wheat including now a cover crop shows that we still have a cover in that cover the 50 percent is basically the spring weed cover pea very aggressive grower the nitrogen fixer are very well covered in this grouse you can see it is 92 percent cover and then rye which is a slower grower in the fall here we have a combination of rye and spring weed and we saw that 76 percent cover great cover now the next slide is kind of looking at the above ground biomass so basically I harvested the whole crop just cutting it above the surface level dried it in in our dryers and then waited so this is dry weight so this is pounds per acre and if you look here pounds per acre of the canola was 11 30 63 pounds so that is a a good number of pounds that was the highest number of pounds for biomass so what I did is I harvested both the cover crop and the wheat so combined is the right column was 12 84 pounds so again that is the highest number so there is the combination between the canola and the wheat so when we look at the next one of course I showed some of the small diet plant so there is still a little bit of cover they have been very limited and the remaining cover is basically the spring wheat so as the spring wheat initially was growing together with the with the soybean there was not as much as they could have been without the crop so here we still benefit from having a cover and it was 185 pounds of biomass produced now P has a very nice biomass as you could see in some of the videos that I showed you here total peas and wheat 1161 pounds rye the last one has limited growth in the fall but still together with the spring we did that's still 760 pounds of dry matter in in the fall so there is always a relationship between amount of cover that you can see and amounts of pound produced so here on the bottom you see the cover percent that I took with the kind of PO reading and then on the left you see the pounds of dry matter that are actually produced so you see there's a nice relationship so that we can kind of express that more cover also indeed resulted in higher levels so the next couple of pictures I'm going to show you a couple of winter rye so coming now out of the dormancy in the spring there will be an amount of dry matter production so here I'm showing several pictures kind of in different locations just to show you kind of what what biomass you can have so this one Morris on 6th of May and not too much yet Lamberton 153 pounds but if you can see in St. Paul where it was warmer it had been better growing conditions that crops takes off and there you already see a 2000 pound crop in roso in May there was also good growing conditions and we had 800 pounds so now the question is when do you terminate this crop in order to grow the main crop but what I was trying to see is the first I showed you numbers from the fall here are a few numbers from the spring growth a lot of growers are utilizing this system to plant soybeans into and this is a green planting system so the growers use the rye planted into the rye and then as the rye was heading out they terminated it with a roller crimper some other experiments are taking place by trying to grow dry beans into residue and so this can also be an effective system to do so the thing about growing a crop in the spring is we need to monitor the moisture in a drier spring we may need to terminate the cover crops a little bit earlier now what about soybeans we've done some experiment also with with soybeans and here's an example of how we use a planter to plant the seeds right into the soybeans and if you look here at the right picture you can see the soybean was still very limited so the idea was early in season you can get in maybe you can get into the crop which you're planting equipment depending on your own spacing till the plants are a little bit taller but at a certain point you cannot go into the plot anymore without doing damage so the same field here we see on the left picture the soybean already has some parts and now we see the camalina growing underneath the crop so one of the trials I did was to use winter camalina 5.3 pounds cereal rye and I planted it into standing soybeans which had majorities of 04, 05, 08, and 09 and I did it at the R7 states of the earliest maturing soybean here a couple of pictures of what it might look like so in the season September we see the soybean is still standing the picture on the right October the soybean is harvested here we compare on the left camalina in October with rye here we comparing in the spring what camalina looked like it starts just to come out of the dormancy starts to grow and here kind of the picture of rye in the fall and in the spring so you can see in the spring quite a bit of growth occurring so what kind of numbers did we see well we saw in camalina the total over and that is in the spring about 250 pounds and rye we saw about 500 pounds so definitely rye has more biomass production in the spring compared with the camalina then I would like to finish up here with showing you that the biomass in the spring in the different maturities differ and you can look here at the last column the combined there was more biomass in what was previously the early maturing soybean because we had more light there for the cover crop to grow however we also need to kind of look at the economics and here I'm looking at the yield of the previous year that is the soybean yield when we interceded the cover crops we did not have any negative effect on the yield but we can see that early maturing definitely was not yielding as much as the late maturing so in summary you should not really select an early maturing variety to benefit a little bit on the biomass produced but you should really look at the full season and then maybe add some biomass so in summary I would say that we have a lot of opportunity to to grow several cover crops and I'm looking to continue with some of the research and I'm always happy to answer any of the questions