Given the shape many fields were left in last fall, some form of reduced tillage should rank high on your list. To fully capitalize on reduced tillage, burndown herbicides will need to be given a lot of consideration.
It appears that this Mississippi soybean season is going to be different from last year. I had hoped for more cold weather and earlier rainfall. With the rains over the last few weeks, I imagine some farmers are beginning to get a little nervous, but it is still early, One thing is for sure: our only option is to wait this weather out.
As I write this (March 21), I realize that it seems late compared to last year, but we experienced an abnormal spring last year, and given the past couple of years, I certainly don't want to be guilty of wishing it would stop raining… certainly not yet.
December 2000 was the second-coldest December ever. I had hoped January and February would follow suit, but they did not. Moisture levels since the first of the year have made many believe the drought of the past three years is over. I believe moisture levels might be deceiving because we are not back to par or where we normally are at this time of the year. We are in much better shape, but not caught up.
The reason for my comments regarding the weather is to emphasize the need to do everything in your power to conserve moisture. Given the shape many fields were left in last fall, some form of reduced tillage should rank high on your list. In order to fully capitalize on reduced tillage, burndown herbicides will need to be given a lot of consideration.
As you have probably seen, vegetative growth is quite variable. The cold weather in December suppressed weed growth in many fields, and saturated conditions have kept a lot of this vegetation from growing off.
These conditions have been a big help as far as what producers needed to do early. Some fields that were tilled in the fall are still clean. Due to saturated soil conditions, we have observed little growth on the low ends of fields, but greater weed densities on the better-drained ends (just not a lot of growth as of yet).
Some general observations:
It appears things are slightly behind, particularly on the clay soils. We made a big effort to look at all our verification fields, particularly in the Delta, since we were having to work with the aerial application restriction. However, based on vegetative growth, we held up spraying most fields until late March. Many fields where vegetation is sparse will not be sprayed, but that is not true of all fields nor was that our original plan.
The key to being successful in reduced tillage is to have everything dead or dying when the planter leaves the field. Don't get caught in a Catch 22 situation of waiting too long and wishing you had done something. Early burndowns are essential to keep fields from drying out in a dry spring. But reverse the situation and lush vegetation will keep a field colder and wetter for an extended period of time.
My goal on burndowns is to put them out as inexpensively as possible. To accomplish this you have to start early… earlier than many I see go out, particularly in the hill area of the state. In a way I have violated my own rules this year by delaying burndowns, but I did it for two reasons: (1) weed growth was not out of hand and (2) vegetative cover was sparse in many fields.
A lot of good options exist, but Roundup/Touchdown are the backbone of most preplant burndown programs. If needed, consider broadening the spectrum by adding materials such as 2,4 — D, Goal, Clarity, Harmony and others. Regardless of your approach, know what is in the field and choose materials according to your needs.
Ironically, the number one question I received last year was, “How do I kill volunteer Roundup Ready soybeans?” This told me in most instances that fields were not scouted well enough to know what was present, and Roundup certainly was not the logical choice. Roundup Ready soybeans or cotton are easy to kill if you use the right products. Personally, I am shocked at how much attention this situation has received this winter.
Volunteer plants are not the norm, why? We typically have wet winters and these seed germinate and die. Last winter it was dry, and we had the greatest percentage of volunteer plants I have ever seen. Several growers kept portions of fields and did not destroy them because they had such good stands, but I'll bet you I can haul every volunteer soybean in this state this year in the back of my truck. This is not going to be an every-year concern, it only occurred because of the dry winter last year.
Keep in mind the opportunity to trim costs of burndowns. This will probably only be accomplished where applied early, but I think that is the only way to go. You know at this time of the year anybody can put out a quart of Roundup and a quart of 2,4 — D and clean up a field, the opportunity for savings comes when you can reduce rates, but this centers around the weeds present in the field and size.
Alan Blaine is the Mississippi Extension soybean specialist. e-mail: firstname.lastname@example.org