The New Agriculture Network's on-line newsletter with seasonal advice for field crop and vegetable growers interested in organic agriculture.

Vol. 2, No. 9 - August 25, 2005

In this issue

	Time travel and soil quality
	New Michigan organic initiative funded
	Reports from organic growers

Next issue posted September 15. Read previous issues through our calendar of issues.

Introduction
History tells us that striking a balance between short-term and long-term strategies is a challenging but critical aspect of sustainable farming. Organic production requires a commitment to the long-term to a greater extent than some other production systems. Agricultural researchers face the challenges of short-term funding, but there have been some pioneering thinkers who established long-term trials decades ago which has lessons for us today.

Cropping system sequence and use of different types and levels of organic inputs are some of the interesting long-term trials that have been established at different locations across North America. Trial designers predicted that there could be long-term consequences of not including in rotation systems the presence of wheat and other small grain cereals or forages that produce substantial root systems and residues for soil amendment. There are often economic incentives where land is in short supply to increase the presence of low-residue producing crops (such as many vegetables) or high nutrient requiring crops such as corn, displacing small grain and cover or forage crops that have important benefits for soil characteristics. For example, wheat contributes a large amount of organic soil input in the form of many fine roots, and winter wheat needs no tillage for 11 months per year - both features that improve soils. Short-term impacts of increased tillage reduced organic inputs and shortened rotations are immediately noticeable and are exploited for short-term economic benefits. But what about the long-term impacts of practices? This question can be answered best with long-term investigations.

Farmers are keenly aware that crop rotation systems and management history are important determinants of soil health and tilth, but information is still limited on the tradeoffs with short-term strategies. For example, how does consistent use of winter cover crops and wheat rotations improve soil quality? Is it advantageous to frost-seed red clover in wheat, and what are the tradeoffs in terms of impact on plant parasitic nematodes, scab and soil organic matter? Is a high organic matter input treatment such as a summer cover crop or application of manure necessary to start improving organic matter? Which cover crops will improve soils the fastest? These are questions that are beginning to be addressed by long-term experiments.

Long-term trials and experimentation
During the 19th Century, a few forward-thinking agricultural scientists around the world realized the great importance of agroecosystem experiments and research for providing information on both short- and long-range impacts of new and emerging agricultural practices. Rothamsted Experimental Station in England was established in 1843; in the U.S., the Morrow Plots were initiated at the University of Illinois in 1876. Both continue today, more than 125 years later. Researchers in each experiment set out to compare relative productivity and soil depletion effects of common crop rotations with un-rotated, continuous crops and the effects of annual application of animal manures. As new agronomic options were developed, these experiments were modified to include new technologies such as no-till planting systems, synthetic fertilizer and pesticide inputs, and organic methods.

More recently, newer long-term studies have been established such as the Long Term Ecological Research project in Michigan (1987), the Long Term Research on Agricultural Systems (LTRAS) project in California (1993), and a number of potato-rotation trials at Montcalm Research Farm by Michigan State University faculty and cooperators, designed to look at effects of rotations, cover crop and manure practices in irrigated potato systems.

Long-term research findings
Important principles in our present-day, basic understanding of agricultural systems are outcomes from these long-term projects. For example, the Morrow Plots quickly demonstrated the yield advantage of rotating crops and of annual manure amendments. Later, these Illinois researchers confirmed the yield benefits of synthetic fertilizers. At the time, this was a very controversial subject.

The graph below shows losses of soil organic matter (SOM) from 1904 to 1973 for three crop rotations in the Morrow plots. Each of the three rotations is either un-amended or amended with a combination of manure, limestone and rock phosphate. Without amendments, the continuous corn plot lost 37% of the SOM present in 1904 while the 2- and 3-year corn rotations lost 26% and 23%, respectively. When these 3 rotations are amended annually, SOM losses are limited to 13%, 6% and 7% for continuous corn, 2-year and 3-year corn rotation, respectively. However, even with manure and a 3-year rotation, 1904 levels of SOM have not been maintained. Findings from other long-term studies suggest that SOM losses can be alleviated further, or even avoided altogether, with a greater inclusion of perennial forages such as hairy vetch, alfalfa or clover in the rotation.

Practical applications of long-term research findings
It is important to keep in mind that low-residue crops such as beans, pickles, onions or potatoes do not return a significant quantity of plant biomass to the soil. These rotations can be improved with cover crops, green manures and other organic amendments. Options for infusing more plant biomass into a low residue vegetable rotation include using a small grain as a rotation crop, including a high-biomass cover crop or amending with compost or manure. A combination of cover crop and manure has shown advantages in a 6-year potato-vegetable rotation study in Michigan.

An important finding for our research has been about the trade-offs between using wheat versus corn as a rotation crop for vegetables. In most cropping years, growing potatoes or a vegetable after wheat, and especially wheat-red clover (frost seeded) rotations, has consistently yielded higher than crops grown after sweet corn. However, in a very cold spring year (2003), corn-based rotations did the best. This may be because soil nitrogen (even when recommended practice of multiple split applications is followed) is tied up by the higher organic matter residue pools in the wheat rotation system. The corn residues appear to have only limited benefit for long-term organic matter, which is the bad news, but on the positive side, they do not tie up nitrogen in a cool spring. Our research continues on how to design a cropping system with the right combination of residue management and combining cover crops with manure or manure with different rotation systems. The goal is to find a combination that releases nitrogen when it is needed (even in cold springs), while still building organic matter.

Soil aggregation or improvements in soil tilth is a key, long-term consequence of rotation sequence and organic inputs. Research is still investigating the effects on legumes such as alfalfa and hairy vetch on soil tilth. There are some new findings that suggest a combination of a legume plus a small grain cereal (wheat, rye or oats) helps build both long-term and short-term aggregation. A mixture of aggregate size and dynamics could well be critical to enhancing soil structure to support aeration, root health and balanced nutrient supply.

Long-term cropping system studies have taught us that even the most recent cropping history of a field can be important for current productivity and trends in SOM. Consider including a 'resting' or 'rebuilding' year wherever possible within the rotation sequence. Instead of a cash crop, grow a high biomass green manure for an effective soil amendment. Grow alfalfa for a season or two, followed by a winter rye cover for a mixture of grass and legume organic inputs. Another shorter-term option might be to plant sorghum-sudan grass or cowpea as a summer soil improvement. Consider these crops in combination with an amendment of manure or compost for additional benefit. Use a winter rye plus hairy vetch cover crop, or a wheat with frost-seeded clover rotation, with a manure amendment to make a positive impact as rapidly as possible in fields where soils have become depleted. Ideas and information on cover crops options for Upper Midwest vegetable and cropping systems can be found at: http://www.covercrops.msu.edu/, and see the MSU soil ecological management website at http://www.safs.msu.edu/soilecology/index.htm.

Conclusions
Management decisions made each day influence short-term success and long-term progress. A well-balanced approach to decision-making can accomplish both short- and long- term productivity and soil improvement goals. If cash crops are consistently followed with a cover crop, and if cover crops are allowed to grow large enough to provide significant biomass, a long-term goal of improving soil tilth and enhancing soil organic matter over time becomes realistic. Emphasis on short-term goals only is not likely to result in maintenance or improvement of soil quality in the long-term. An occasional 'rebuilding' year is important to include when planning field operations to bring a depleted field back up to full potential.

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New Michigan organic initiative funded!
Sieglinde Snapp,
Michigan State University, Horticulture

We are happy to announce an exciting development of approximately $800,000 in funding to support organic transitioning and current farmers in Michigan. MSU's Sieglinde Snapp, Dale Mutch, Mathieu Ngouajio, John Biernbaum, Jim Bingen, Mike Brewer, Ed Grafius, Joy Landis and George Bird, are partnering with MOFFA, MIFFS and Michigan farmers on this grant.

The support is from the Organic USDA program and will provide opportunities for cutting edge, participatory research and extension conducted on farms and on research stations. We will work in close partnership with farmers, educators and advisors from the public and private sector. This builds on the long history in Michigan of working together to improve organic production practices. On-going initiatives that support organic growers in the Upper Midwest include the New Ag Network, the pioneering long-term research trials at the Kellogg Biological Station and the organic orchard demonstration at Clarksville, among other projects.

The focus of our Partnering to Cultivate Organic Agriculture in Michigan and the Midwest grant will be on integrating research, marketing, outreach and education to address issues of top priority to Michigan organic producers (current and transitioning farmers). Top priorities will be decided with farmers, but we are anticipating a focus on understanding of processes that allow prediction and biological management of nutrients and insects. The variability of the weather over the growing season and the undeveloped nature of organic marketing are important challenges in the Upper Midwest and will be addressed by partners within this multidisciplinary effort. Weed management is the priority of other initiatives in the region, so our focus will be primarily on soils and arthopods, although we realize that these will interact with other components of cropping system management.Key responsibilities are outlined below, so that those interested in collaborating can contact us:
- Snapp provides overall coordination for the group and soil/nutrient management.
- Mutch will lead organic field crop activities and New Ag Network outreach with Landis.
- Ngouajio will lead organic vegetables activities.
- Bingen and Conner will take the lead on marketing aspects.
- Brewer and Grafius will work on insect management and Bird on nematodes.
- Biernbaum will focus on organic curriculum.
 
As we learn together, we will be actively engaged with farmers through the New Ag Network, on-farm research activities and farmer visits. Experiential learning and findings from our community of practice will form the basis for organic curriculum, providing direct support for future organic farmers. Please feel free to contact us individually, or Sieg at snapp@msu.edu 517-355-5191 x1417. We are very excited about receiving this support, and look forward to working with you interested extension educators, and current and new organic farm families in Michigan and the Great Lakes region.

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Indiana
Northern Indiana - Dan Flotow

The weather has been the same all summer hot and dry. The last few days and the next few are better-cooler and not humid. I, like most everyone else, could use some more rain. I'm surviving but not really thriving. Yields on some crops are definitely down-like potatoes and green beans.

We continue to harvest for our CSA members, the organic farm market we attend and for the stand here at the farm. We have started selling some veggies to the Natural Foods store in Fort Wayne and are currently talking to the new Fresh Market store that just opened here in Fort Wayne. We are currently harvesting lots of the following crops-summer squash, zucchini, cucumbers, tomatoes and peppers. We continue to plant new crops every week like lettuce, beets, turnips, kohlrabi and pak choi. Two weeks ago, we planted fall snow peas.

The next two weeks will see us start to harvest winter squashes. The other big chore that we will be starting is preparing beds for next year-roto-tilling the beds, mounding the beds back up, adding aged horse manure to as many as we can and planting a cover crop in all beds.

South Central Indiana - Dale Rhoads
In the past two weeks we've had three storms with torrential rain and damaging winds. Along with temperatures in the mid 90s, the beating down of the salad greens temporarily brought salad greens production to an end. Our soils form and crust after hard rains. This has made germination more difficult for all our fall crops, broccoli and kales etc. Spotty germination is going to affect our fall crops/income. Tomato harvest has been good and is starting to wind up. European and Asian pear varieties have started ripening. Good harvest.

Currently we are planting all available space to salad greens to hold through the fall, some to go under row covers, some planted later in greenhouses. We finished planting fall crops, weeding fall crops and keeping up with harvesting.

During the next two weeks we'll be doing the same as what we're doing right now. At the end of this period we could begin pulling tomatoes out of greenhouse.

Questions
Two weeks ago during the call I spoke with someone about summertime cilantro production. Who was that? What region do you live in? We also had our cilantro plants just die this summer and thought it was just the season. We are going to do some trials with it next year under shade cloths to see it that helps germination and survival. Also I spoke with some guys about tomatoes. I wondered if it would be worthwhile if the people that wanted to would do a short write-up on tomato varieties, planting spaces, estimated yields, cultural practices etc., and if that would be good for the readers of the NAN website. I would be willing to provide that information.

Illinois
Northeastern Illinois - Dave Campbell
Very generous rains have given us 3.8 inches of rain for the month -- all of which have come since August 10. Pollination of corn appears to be better than what I had once thought. Beans continue to look good. Buckwheat is almost knee-high and looks very good. Buckwheat was planted on July 28 and 29. Currently, I've been doing repair and maintenance of equipment, as well as mowing off grass and weeds around field borders. In the next two weeks, I will sell old crop soybeans and clip weeds with my haybine in the oats/red clover fields.

Michigan
Southeast Michigan - John Simmons
All small grains have been harvested. Spelt ran about 80 bushels per acre while oats yielded 70 bushels per acre.

I have run one pass to evaluate harvesting red clover seed.

Sunflowers and soybeans are doing great. The soybean aphid has not exceeded 100 aphids per plant in my fields, but conventional farmers in the area are spraying like crazy.

It has turned into a productive, good growing season.

Southeast Michigan - Rob Malcomnson
Dry weather has hurt third cutting growth. Currently we are harvesting vegetables. In the next two weeks we plan to prep combine and wagons

Iowa
Northwest Iowa - Paul Mugge
The weather has been pleasant and the corn and soybeans look great. This is the slack time. Not much going on for field work. I hauled enough liquid manure to get me by until fall and am still pulling button weeds in the beans, but that never ends. In the next two weeks I will have to mow the clover which was underseeded in the oats and flax because of a weed here and there.

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