by Kevin Archibald

When we became serious about trying zero tillage in the 1980's, the last thing on our minds was coping with wet soil conditions. In fact, part of the impetus for moving to a direct seeding system was the poor seedbed conditions we experienced in many of the years of the last decade. Dry, loose soil which led to poor germination and uneven emergence was common. We often had to seed deep to try to reach moisture and this produced weak unthrifty plants.

Zero tillage solved many of the shortcomings that conventional systems left wanting. Standing stubble trapped snow during the winter and lowered evaporation rates in spring providing critically needed moisture.

Those dry years in the late 1980's offered no hint of ever having to cope with wet soils again. But substantial rains in the fall of 1994, a heavy snowfall through into the spring of 1995 and a late damp spring changed that perspective. For the first time in more than a decade we were faced with seeding conditions that were best described as boggy.

Some truths became evident early that spring. Clearly, fields that had been under zero tillage for 5 to 7 years were the earliest fields to be seeded. There was a much greater degree of trafficability on these fields, but, this trafficability decreased greatly on fields that had been under our no-till system for only 2 years, and these fields were just plain wet. We tried burning the residue (which was wheat stubble) on one such field thinking that exposing the soil to sun and wind would hasten our ability to seed it. This did not prove to be true. We also observed that the soil seemed a degree or two colder than in previous years, which we attributed to the excess moisture present, and this did present emergence problems in canola we felt was seeded too deep for those conditions.

When it seemed clear that the moisture profile in our soil had remained high, it was certain that the chance of soggy soil conditions would persist. Thusly, a plan to deal with seeding in wet situations was essential.

The entire premise of dealing with wet seeding conditions is based on proper planning. And, while some of the concepts I will outline are basic to many farm operations, including these in our practises ensured success in the mud.

The major techniques that helped us make it through the last two wet springs are:

a) fall fertilization

b) low residue crops in the rotation

c) controlling winter annual weeds

d) seeding as shallow as possible

e) consider winter wheat or fall rye

We will deal with each of these items in succession.

First, fall fertilization in the form of anhydrous ammonia was a standard practise when we used to conventionally till. Fall applied NH3 is more tillage than we originally wanted in our cropping system, but in our soil it really helps to speed spring seeding. When applied with 3/4" knives on 12" spacing, NH3 knifed in standing stubble barely makes a mark. In heavy residue we find we have to work on an angle to find the mark of the previous pass. But despite low soil disturbance, NH3 knifed in the fall seems to; produce enough black soil to aid us in getting on fields early. Also, time savings are also gained as there is less fertilizer product to haul in spring, and remember, wet springs are often late seasons as well.

Low residue crops such as lentils, peas, or canola included in the rotation are also considered an important part of our plan. Most low residue crops trap less snow and allow soils to warm quicker during the spring. We find that by keeping half of our acres each year in broadleaf crops we greatly increase our ability to manage a wet spring. Of course, crop rotation is important to help control leaf diseases as well.

We have always sprayed for fall and winter annual weeds, and the importance of this operation cannot be understated when wet conditions are expected in spring. Winter weeds really get started early in the season if left uncontrolled, and can cause serious problems if fieldwork has to be delayed. They can thrive in cool weather, and even though well established no-till fields allow early traffic, by the time a spraying operation may be able to performed, winter annuals could have used up valuable nutrients.

Shallow seeding is important to every zero till system, but when seeding in wet soils, shallow seeding is absolutely critical. Wet soil is definitely cooler, and delayed emergence will result if seeds are placed deeper than 1/2".

The fall of 1996 allowed us to plant some winter wheat, something we have been attempting to do now for two years. We operate some land that has an unusually high water table, and in wetter years such as in recent history, this land is hard to get seeded early. We are hoping that fall seeded crops such as winter wheat, will do well on these fields, and take some pressure off of our spring workload.

I have just outlined some of the basic practises that enable us to cope with seeding in wet spring soil conditions. The one principal I have not touched on yet is patience, and this could well be the most important. There will be certain fields and particular times when even the best laid plans can be upset or derailed. Our experience is that patience pays dividends during these times. Burning residue or running for a cultivator will usually result in lower yields and higher operating costs, plus a loss of confidence in one's ability to manage a no-till system.

Zero till cropping is an art. Part of practising the art is learning to deal with changing conditions, and this includes the wet soils situation. It can definitely be a challenge, but with proper planning and a degree of patience, no-till seeding in wet conditions is manageable. And when we think of what is at stake, it is definitely worth the challenge.