The year is 1988 and a brand new air seeder has just been delivered to our farm. We were about to be disappointed. The top layer of dirt on our summerfallow was dry dust. If we still had discers, the seeding operation would have turned up moist, lumpy soil and problems with blowing would have been greatly reduced. This was not the case and our first experience with seeding lentils on summerfallow was a bust. That field was eventually reseeded to durum.
Now let us skip a year to the spring of 1989. The durum stubble field had straw about 6 inches high with a 1 inch layer of powdery soil, just like ashes. We took an old set of Massey #63 double disc drills and seeded lentils into that stubble. When it rained, I was able to observe a magical sight of all these little furrows filling up with rainwater. In June, the temperature soared and there were great losses in the lentils due to heat canker (heat canker is when the ground gets so hot that it sears the plant stem, killing it). In those little furrows, the lentils and ground were partially protected from the hot sun and the wind by the standing stubble. RESULTS: one of the best crops of lentils we have ever grown (30 bushels/acre).
I was hooked. I was hooked on leaving the stubble standing through the seeding process, hooked on minimal soil disturbance to retain soil moisture and hooked on the protection of those small plants from hot spring winds. However, doing this takes lots of sacrifices. Mechanical weed control has been severely curtailed. Mechanical incorporation of chemicals has gone out the window. You just can't go wham, change the whole farm over. Every year is different. New weed problems arise. Direct, minimal soil disturbance seeding looks great for seeding lentils. When we seed durum, we are looking at options such as using a bolt-on wing system which cuts through the soil somewhat like a noble blade, or just keep on seeding with knives.
Anyways, I will try to give you an overview of what we try to do on our farm. Sometimes it works.
Preparation for the crop begins at harvest time. We straight cut the crop as high as we possibly can. This is to increase snow trapping and also to have less straw and chaff to spread. We have a hydraulic powered spreader on the combine which does an excellent job of getting the trash back out over the width of the cut.
Fall spraying with 2,4-D helps control the winter annuals can be a major problem in any crop and even more so in lentils. Once the ground has cooled off, we try to get granular herbicides applied. We use Fortress on a lot of fields for control of wild oats, wild millet, and suppression of buckwheat. The ground to be seeded to lentils gets a little stronger medicine consisting of Edge and Avadex. This seems to do a good job of controlling volunteer durum and broadleaf weeds such as kochia and Russian thistle. The Avadex helps to control wild oats which germinate deeper in the soil. Surface application is pretty new science to me and it still has to prove itself.
We spray if necessary in the spring. If the fall spraying and granular herbicides work, we should not have to spray in the spring. BUT if we do, Roundup is used where lentils are planted and Rustler is used where the durum is seeded. On our farm, we use 1/2 litre per acre of either herbicide. A neighbour has applied a 3/4 rate of Rustler on his wheat and did not have to spray for broadleaf weeds later on.
In crop weed control consists of using a double tank sprayer with each tank having its own set of booms, etc.. Again, lentils need that special treatment. Sencor, at full strength, can have harmful effects on a lentil crop. Therefore, we spray about 3/4 rate with full intentions of coming back and hitting the crop later on with a second shot at the same rate. This is applied at 10-15 gallons per acre of water. The small tank contains Poast and is used for grassy weed control. This is spot sprayed using 5 gallons per acre of water. Poast cost us about 64 cents per acre last year. Durum is sprayed with what ever works for broadleaf weed control as long as it does not conflict with the grassy weed control. In the past, we have used 2,4-D, Buctril M, and Dyvel (they gave us a jug to try). Banvel works great, BUT it can gas off and drift onto a susceptible crop. Then look out!
About 25% of the acres are fallow and about 99% of these acres are chem fallowed. After seeding durum into lentil stubble, the amount of trash left on the field is just not enough to allow cultivation. I guess I should point out that even though the soil is high quality sandy loam to clay loam, it blows very easily. Spraying with Rustler has been our main tool to combat weeds until recently. With so many neighbours starting to grow susceptible crops, we have also been using Roundup and if necessary, mixing Express Pak with it for buckwheat control.
Just a note before I close. Chemfallow has created a new problem. The increased snow catch on our fallow fields have caused water erosion in the draws so we may have to continuous crop the waterways.
My presentation today is made from my own observations and experiences. Some of the things I have tried have not worked and of course some have. Whether any of these things will work on your farm is something you will have to figure out. With good luck and an open mind, I hope you will find a system that works for you.