Cover crops are helping to increase yields in Iowa corn fields. My friend Sarah Carlson from Practical Farmers of Iowa sent me the following testimonial from Eric Franzenburg from east central Iowa (about 1.5 hours east of Ames).
Thanks to Sarah and Eric for making this testimonial public. I know that there are many other farmers that have seen similar results. If you have and would like to share with the readers of plantcovercrops.com I’d greatly appreciate it!
I believe that the researcher from the article is on to something in regard to relieving drought stress (research I proposed on this blog).
I went out to do some yield checks on our conventional corn fields about a week ago to get an idea where we were. One of the fields was seeded with fall rye earlier in the fall (September 1, 2011), followed by 3,000 gallons/A of hog manure (later in the fall). This spring we killed the rye with Roundup when the rye was over knee high, waited over 2 weeks to plant, tilled one pass with tandem disk-harrow, and planted later in May. It was the last field I planted.
I followed with a sidedress of 70 lbs at V6. This field will out-yield all other fields by 40 bpa. The plant health is excellent, and I was telling Sarah that if you start poking around looking for rye residue it is virtually gone (not sure if this is good or bad).
We have been doing this same program for 4 years now and I am no longer worried about planting corn the third week of May under these conditions, especially after this year; this has been a very telling growing season. We are coming up with the same results 3 of the 4 years (yields 20-40 bu. higher).
I have been wondering what the mechanisms in the soil are that have given us these results. While the scenario that the researcher has proposed sounds good, it does not sound like much work has been done to prove this out.