This is the time of the year when the Saskatchewan Conservation Learning Centre releases its results for the 1997 field season. The written report, Field Results 1997, covers most of the 40 projects in progress, including those involving annual crops, forages and trees. Due to the variable landscape of the CLC, many projects consider topography in the results. The following are a few highlights regarding landscape effects from our Field Results Report for 1997.
If you were to use GPS technology to help you produce a consistently high wheat protein content across a field, how would you do it? That is a question that we started to address this summer at the Saskatchewan Conservation Learning Centre.
For a first attempt, we performed a very simple test. A hard red spring wheat (AC Splendor) field was fertilized according to soil test recommendations generated by sampling the mid-slope positions of a pothole landscape. We experienced a very wet spring, whereas July and August precipitation was almost nil.
At harvest, samples of grain were taken from the lowest, middle (well-drained) and upper (but most level) slopes. What protein levels would you expect? Since we think of drier weather conditions usually resulting in higher proteins, would you think that the most well-drained slopes would grow the highest protein crop?
In fact, the lower slopes produced the highest protein wheat. In three of four side by side strips, the lowest slope produced the highest proteins, the well-drained middle slope produced the next highest protein, and the highest but most level slope produced the lowest protein levels. So, the lower slope positions, which would have more moisture throughout the growing season, have yielded the highest protein levels in 1997 at our site. This may be due to higher available levels of nitrogen. We'll follow up with more experiments in 1998 to try to better understand how wheat protein is affected by the landscape and fertilizer applications at the CLC.
Another project, this one conducted by Dr. Randy Kutcher of the Melfort Research Farm (Agriculture and Agri-Food Canada), looked at what trends there are with crop disease and the topography. Why? There may be benefits to applying fungicides only on the areas of the field where crop diseases are likely to occur.
Kutcher=s results at the CLC last summer show there were significant differences in the incidence and severity of alternaria in polish canola within the landscape. The disease increased in severity from upper to lower slope positions. Application of a fungicide (Rovral Flo) reduced the disease severity on all slope positions. However, a yield increase on sprayed over unsprayed plots was detected only on the lower slope positions. So, this leads Kutcher to suggest that an application of fungicide only to slope positions where it increases yield or quality should increase net returns to producers and possibly reduce the environmental impact of fungicides.
A three year project to look at the safety of anhydrous ammonia in a one-pass direct seeding system is now complete at the CLC. Dr. Alex Matus of the University of Sask. Soil Science Department and Mr. Garry Hnatowich of Sask. Wheat Pool have been comparing the use of some different openers used for applying anhydrous ammonia while seeding wheat.
The results show that adequate separation can be achieved with both the Flexi-Coil side banding opener and a sweep with Froc boot opener. Some of the earlier results showed that some paired row openers were not as successful at separating the seed from the fertilizer. Also, packing was of great importance to keep the anhydrous from escaping, especially in the wetter soils often found at lower slope positions.
Who knows more about a piece of land, but the farmer who works on it? Nobody, usually. But, there are some farmers, who although they are confident in that fact, still wish to know more. Visual images and maps of fields often have a great impact on our understanding of the land.
A number of projects and activities at the Conservation Learning Centre have included some sort of mapping of different factors affecting yield. Grid soil nutrient sampling, grid monitoring with root simulator probes, soil surveys, topography surveys, landscape element judgements -- all of these have been used so far at the CLC. Farmers in the province are also now using yield maps from combines to generate a mass of information -- causing some challenges in interpreting them, but having the potential for easy comparisons from year to year and with other maps. Others are investing in combine yield monitors without the mapping capabilities, losing the ability to refer to a hard copy of results, but still providing some valuable impressions.
Some producers are not really wanting to invest the finances or the time to use some of these methods, but still want to know a little more about their land and results of their own experiments. One of the most useful and interesting mapping tools is any type of aerial photograph. I find that often what is invisible from the ground becomes very obvious from the air. It may be as simple as spending $100.00 to fly over the farm, maybe taking a few photographs while you're up there.
Soil survey maps can be useful for a general understanding of the land and its capabilities. Also, there are black and white photos which the province and some other agencies can show you. If you live along a highway, the province often takes aerial photographs of the land including a highway and these are available for a low cost. They are repeatedly photographed, so if you can get these, they can provide a history of moisture cycles, productivity, changes in field boundaries and land use.
Another useful type of photograph is the infra-red image. It shows the most lush crops as deeper red, while the summer fallow appears green and the water appears black. What is great about these, is that you can get a quarter or full section image, and still be able to pick out three foot wide misses or overlaps in spraying or even a walking path. So, you can get a very good idea of what areas of a field are more or less productive. The next step is to attempt to explain the variation from your own in-depth knowledge of field history and treatments. Even improper field equipment settings can often be seen from the photos.
Infra-red photos are usually taken in mid-summer, so that the differences in lushness of a crop is accentuated. Prairie Agri Photo in Carman, Manitoba is often contracted to do this type of photography. Understandably, the cost per photo decreases with more photos required in an area, so it helps to get some neighbours together to get a better price.
These are just a few things you can do with mapping and photos. It all helps for discovering more about what practices pay and don't pay. It certainly sparks more curiosity about what is really happening in your fields.