TAKING OUT CRP

 

     This post is prompted from watching a disaster in transitioning a CRP field back to cropping.  If you want to retain the soil benefits gained during the years in CRP, the takeout process is not simple.  Timing for each operation, weather, CRP cultivars in the field, crop choice, and long term goal for the field are among the factors that need consideration.   Cultivating the hell out of it and planting wheat as quickly as possible puts the field back nearly to conditions prior to CRP.   I'm sure the initial interest of this farmer was to save the benefits that accumulated over the years of CRP by doing a no-till conversion.  This property needed the CRP benefit.  It contains 6 soil types, and has a lot of shallow depth soil and suffered from OM loss through many years of cultivation and associated erosion.  The mistake in my opinion was wanting to seed a cash crop too quickly without sanitizing the field.  It is a very common and strong emotional pull, --to get the field producing.   The takeout process started with poor fall regrowth of CRP cultivars making it impossible to get good chemical uptake.  The following spring the field was chemicaled and seeded to spring barley.  Seeding a grass cash crop as the first crop into an unsanitized 10 year old grass field is not a good no-till practice.  The second year crop was garbanzo beans.  That was OK, it gave crop diversity, except CRP cultivars were still numerous, garbs are a high moisture user, and the moisture recharge was poor.  The third crop is winter wheat that was seeded very late following extensive (but not whole field) discing to remove the worst of the CRP cultivars, in a moisture depleted field.  The field is still contaminated in many areas with unwanted weedy cultivars growing with the sparse stand of winter wheat.  The soil structure and other soil related benefits that were built up over the years in CRP has been severely damaged.  People watching this field will come to one of two conclusions depending on their preconceived attitude, (1) that no-till does not work, or (2) this field was not properly prepared for no-till.
      Successful long term no-tilling requires (1) patience, (2) field sanitation, (3) crop selection to fit the conditions and limitations you have at the moment, (4) crop diversity, (5) good timing for all field operations.
     Since 2002 we have taken out 4 fields of CRP.   Of the four, we got the last one right.  That field was given the time for proper sanitation.  Other than roughness, mainly do to rodent mounds built over the years, the field is in excellent shape, with normal CRP and weedy species gone.   The 2" of worm castings that make up the surface layer of the soil, soil structure and most of the other benefits developed over the years of CRP are intact. The first crop, winter wheat, was planted following an extended period of chemical fallow (sanitation period).  The field was seeded with the CrossSlot drill to winter wheat looked beautiful, it was clean, and had an excellent yield.  We had a companion field converted at the same time, where we spring seeded a five cultivar cover crop instead of continuing with chemical fallow.  The sanitation rule for successful no-tilling was not followed and we have weed and rodent issues on that field.   The field yielded approximately 10bu/ac less, which in this case was still excellent at nearly 100 bu/ac.   This takeout method had two problems.  (1) --was a great environment for rodents with good food source and great housing and protection from predators.  They harmed numerous areas during the winter that never recovered completely leaving the field looking ragged.  (2) --a number of weedy cultivars grew with the crop and increased the seed bank.  Other than the abundance of rattail fescue, I'm not overly concerned about the weedy cultivars.  The worm castings and soil structure are still intact from the years in CRP, and we were able to keep living roots in the ground to feed the micro biology for most of the non crop time.  The question is, --over time will the benefits from this cover crop outweigh the problems that remain.
      [update: 9/23/19]   We have found out the hard way that weeds, where it is necessary to use harsh chemicals like Tordon (Picloram), or Stinger (clopyralid), need to be removed during the time the field is in CRP.  Harsh chemicals will likely limit the cultivars available for cash cropping because of plant back issues.  One of these weeds is Rush Skeleton Weed.  This weed has infested thousands of acres of pasture land and CRP fields.  It becomes deep rooted.  There are leaves only on the ground hugging rosette.  While you can reduce seed production by burning off the branching tops, you will not control it by a burn down method.  Cultivation breaks up the root system and increases the density and area of infestation.  The key to control is timing of application so the plant will take some of the chemistry into the root, --notably in late fall after a frost.   A number of chemistries will control new plants before they establish a root system.  Good control of established plants will require repeated chemical applications.