A farmer-researcher collaborative effort to design no-till systems appropriate for small-scale organic producers in Alabama and the Deep South

A farmer-researcher collaborative effort to design no-till systems appropriate for small-scale organic producers in Alabama and the Deep South

Summary

The purpose of this project is for researchers and farmers to collaborate to develop effective strategies for organic no till management in small scale vegetable production systems. Since each farm is unique in its location, soil type, crops grown, and the inclusion of livestock into their farming operation, it is unlikely that a growing technique can be developed on a research station that would be applicable to all small scale organic farms. Also, since the farmer is the expert about his/her particular farm ecosystem, he/she would have the best chance at success. In this project, we are using the term “organic” to include farming practices that would be acceptable in certified organic systems, those that do not use chemical inputs such as herbicides, insecticides, or fertilizers. No till farming techniques have been worked out for large scale conventional farmers that rely on the use of herbicides and roller crimpers to kill the cover crop, chemical fertilizers to make nutrients more available to the emerging cover crop, and no till seeders and transplanters for planting the cash crop into the cover crop residue; but appropriate techniques have not been developed for small scale farmers who do not have these chemical inputs and large equipment at their disposal. Consequently, there are significant challenges in adopting the practice to organic systems. For example, timing becomes critical in organic systems. Without the use of herbicides, the cover crop must be terminated by rolling and crimping or mowing at the exact time when it is most vulnerable to kill, that is at the soft dough stage of grains, for example, and it must be left to dry down for a couple of weeks before planting the next crop into the residue. Since fast-release chemical fertilizers are not used in organic systems, nitrogen and other nutrients that will be needed for the subsequent cash crop to get a fast start, will have to be supplied by either a legume in the cover crop mix, or abundant amounts of compost for pre-plant application. Then, since herbicides and tillage are not available in the tool box of organic no-till farmers, the system relies on a heavy cover crop residue to keep weeds from emerging in the cash crop during the growing season. Also, most small scale farmers do not have the need for or access to the large, expensive implements that have been designed for NT farming on a large scale. Category 1 tractors, which are appropriate for small scale production may not be large enough to operate some of the NT equipment. So, another aspect of this project is to design equipment suitable for small scale NT farming, and for farmers to invent their own ways to get the job done. For example, one farmer in NC uses his tiller with the tines unengaged to roll and crimp his cover crop.

Objectives/Performance Targets

1. Establish a collaborative effort between farmers and researchers to identify NT production methods that are appropriate for a variety of crops, soil types, and farming scales suitable for organic vegetable production in the Deep South.
2. Evaluate the effectiveness of various high residue cover crops and mixtures for ease of growth, maintenance of soil fertility, and weed control.
3. Evaluate tillage treatments across various soil types, cash crops, and cover crops, with respect to soil fertility, weed control, crop yield, and farmer acceptance.
4. Evaluate the effects of different pre-plant fertilizer rates on crop yield, weed populations, and cover crop growth.
5. Expand NT production practices in AL by assisting small-scale farmers in the state with the implementation of organic NT practices.

Accomplishments/Milestones

Farm 1:
Plan: To establish a good summer cover crop and follow it with fall-planted garlic.
Results: The farmer did not get a good enough summer cover crop to control weeds and produce mulch for the subsequent cash crop. Due to summer drought, the foxtail millet did not grow well, but the sunnhemp did much better. Unfortunately, only a small amount of sunnhemp had been planted. Due to failure of the summer cover crop, the farmer will need to start over and till to establish the garlic, and then plans to mulch with wood chips to control weeds.
Farm 2:
Plan: This farmer planted a fall cover crop of Austrian winter pea last fall, flail mowed it, and then planted lettuce and early spring brassicas into the residue.
Results: The Austrian winter pea did not grow back and present a problem to the establishment and growth of the subsequent cash crop, but it decomposed rapidly and did not prevent the growth of summer weeds. Iron clay pea was planted in late summer and following winter kill, brassicas and lettuce would be planted here again.
In a larger area of the farm, covering about 3 acres, this farmer had planted a fall cover crop of black oat and lupine. It was rolled and crimped and squash and cantaloupe seedlings were transplanted into the residue. This system worked well due to the large amount of residue produced by the fall cover crop. The farmer reported a good success overall with low amounts of weeds and high transplant survival. The mulched area of the field had a consistently lower temperature and higher moisture content than the non-mulched area. Picking was much more pleasant and the harvest trucks could be driven into the field even when wet. There was less dust and it was easier to walk on the mulch than on the bare soil.
Farm 3:
Plan: Plant Austrian winter pea in the fall, roll it in the spring, and plant corn into the residue.
Results: The Austrian winter cover crop failed due to very cold weather and it was in a low-lying area that stayed too wet this winter. It was decided to move the project to a higher field. The new field was tilled and planted to iron and clay peas. Due to drought and deer, it was a mediocre summer cover crop, but there was enough weed control to sow a winter cover crop of rye and hairy vetch into the standing peas and let them winter kill or mow over the seed to cover it. This field is set up now to the point where NT could succeed if care is taken to keep the soil covered with either a cover crop or a crop.
Farm 4:
Plan:
This farmer started with a field of Bermuda grass, which was tilled and planted to Austrian winter pea in the fall. The objective was to try to get a good cover crop stand that would produce enough mulch to suppress the grass. In the summer, ½ of the field would be tilled and ½ not tilled. Half of each tillage treatment would be planted to corn and ½ to a summer cover crop.
Results:
The Austrian winter pea did not grow well due to very cold winter temperatures. So, the farmer started over and tilled the whole field in the spring and planted corn and buckwheat. Due to the drought, neither summer crop produced enough biomass to suppress the Bermuda grass and it grew back. Pigeon pea was also overseeded into the corn, but it failed. At the end of the summer, the field was full of Bermuda grass. The farmer overseeded oats into the grass, but at the time of the farm visit in October, none of it was visible in the grass cover. This farmer needs to get an alternative crop established in the field to suppress the Bermuda grass before practicing NT.
Farm 5:
Plan:
This farm started the NT project in the spring by tilling a field of grass and planting summer peas. Brassicas, such as broccoli, Brussels sprouts, and cabbage would be planted into the standing peas.
Results:
The peas were irrigated and produced a good stand. Brassicas were planted between the rows of peas. The pea plants were laid over out of the way of the brassica seedlings. The plan was to try to harvest some peas before frost killed them. The peas frost-killed and the brassicas are growing well. This field is set up to continue NT if the field is kept continuously covered with a cover crop or cash crop to prevent grass from invading.

Research station results:
Cullman:

One experiment involved planting corn following a fall cover crop of rye, crimson clover, and hairy vetch. The field was divided into 3 sections as follows:
1. Corn planted in year one
2. Corn planted in year two
3. Corn planted in year three
So that in section 1 corn followed 1 season of cover crops, in section 2 corn followed 3 seasons of cover crops, and in section 3 corn followed 5 seasons of cover crops. The objective was to determine how many seasons of cover crops it would take to gain control of the weeds in an organic no-till system. Conventional till and no-till systems were compared.
Results:
The first year corn crop was a failure due to pests, droughts, and weeds.
Also, different cover crops were grown and biomass and weed suppression were compared.
E.V. Smith:
Various cover crops were grown and biomass and weed suppression were compared.
Results:
The cover crop data have not yet been analyzed.

Impacts and Contributions/Outcomes

We held 3 field days and invited the public to come and observe the no-till trials on two of the farms and on one of the research stations. We brought equipment and demonstrated their use. We explained the benefits of no-till production and participants were shown cover crops growing in the field. About 75 people attended the field days.

All of the farmers are making progress toward developing an effective no-till system. Two of them are at the point of being able to establish a cash crop this summer without needing to till. The other 3 are adapting their approaches to insure success in the future.

Collaborators: