Holistic Organics and Biostrip Intercropping
Brian Caldwell, Extension Educator

This systems approach to vegetable production is based on holistic organic pest control practices that integrate room and board for beneficials - a protective sod habitat with its wildflower pollen/nectar food sources -- right into the field alongside the crops, in a form of practical permanent agriculture. Although scouts have found just about every pest common to Northeast vegetables at Ruckytucks Farm, none have been in significant enough numbers to threaten the crops. The scouts have also found an abundance of beneficials. The result is that we have not had to use any pest controls at all, including Bts, for the past eight years now.

Ruckytucks Farm in Saratoga, New York has been certified organic since its inception in 1990, growing some 140 varieties of vegetables for area restaurants and a CSA. There are 10 acres under cultivation with 5 to 6 in intensive production. The climate is marginal Zone 5: frosts are likely until the end of May and can come as early as mid-September. The soils are clay based and prone to cracking during dry periods and waterlogging when too wet -- although both extremes are being ameliorated by the wide scale use of cover crops and compost, particularly aquatic weeds delivered from a nearby lake weed harvesting operation.

The entire farm is laid out in permanent raised beds which effectively provide a compaction free zone quick to warm up in the Spring. Building and maintaining high soil fertility in the beds through rotations, cover cropping and compost is a primary farm focus. The resulting high organic matter content promotes both drainage and moisture holding capacity and enhances root growth.

Primary tillage and bed formation is provided by a 52" Kuhn rotovator rear mounted on an International 340 wide front tractor with the wheels set up to straddle the beds. Additional cultivation of the beds is with an Allis Chalmers "G", also set to wide wheel spacing and by hand with stirrup hoes. Both mechanical and foot compaction is limited to the sod strips between the beds for all the tillage, planting, harvest, mowing and soil building operations.

Some time ago I began questioning the validity of keeping the strips between the beds clean cultivated. What has evolved over time are permanent sod strips, sown partially to Dutch White clover but also containing diverse perennial grasses, wild herbs and wildflowers that grew in naturally. Noxious perennial weed species such as quack grass and thistle were mostly eliminated by whole field repeated cultivations before the beds were formed.

A holistic farming system has been evolving over the past 10 years or so on my farm and on others throughout the northeast based on an organic systems approach. At its core is soil fertility management. The aim is to build up organic matter to feed the soil and create a well-aggregated habitat for diverse species of beneficial organisms that colonize the rhizosphere to prevent disease and mineralize nutrients for crop growth. Important recent
resources utilizing this approach include Building Soils for Better Crops by Fred Magdoff and Harold van Es, Edaphos by Paul Sachs and Elaine Ingham¹s Soil Foodweb research available at www.soilfoodweb.com.

The functions of the below ground ecosystem are integrated with the enhanced above ground habitat. Also known as "strip insectary intercropping" these biostrips serve a multitude of functions:

· They provide solid, muck free footing for the tractor and the farmers, particularly when the fields are wet in the Spring or after heavy rains.

· Over 1/3 of the entire farm is now in permanent cover all of the time preventing and providing barriers to soil and wind erosion. The beds themselves are sown to specific cover crops when not in crop production particularly over the Winter, providing nearly 100% soil coverage most of the time.

· When allowed to grow (not mowed) the "wildflowers of the week/month" that grow in become important pollen and nectar food sources for beneficial insects and pollinators. The strips are bright yellow with dandelions in the Spring, white with Queen Anne's Lace in late Summer, and so on. Early wildflower food sources help establish increased populations of beneficials ready to prey on pest species when they arrive on the scene. Each wave of wildflowers is mowed before going to seed, except for the white clover to help promote increased stands.

· The biostrips also offer protective habitat -- right in the field, side by side with the crops -- for the beneficials. For pest species it's literally a hostile jungle out there with enemies lurking everywhere. The permanent strips also provide an overwintering habitat for large populations of beneficials, helping to magnify their presence early in the following growing season.

· All the beds are numbered and spread sheets are used to manage rotations so that no bed is planted back to the same crop family for at least three years. Also, crop families are kept spaced apart in the field to maximize plant community diversity and prevent monocropping situations that breed up pest populations and disease pressure.

· The sod strips seem to maintain a full time deep rooted connection to the falling water table in the heat of the summer, providing a positive upwards hydraulic action that also benefits the more shallow rooted crops in the beds in between.

· The mycorrhizae residing in the biostrips colonize the crop beds in between, acting as water and nutrient pipelines for the crop¹s root system. The beds themselves are planted to more intensive spacings and the denser plant canopies help shade the soil, conserving moisture during droughty periods and providing additional habitat for beneficials.

· A "mow and blow" system utilizes a heavy duty rotary mower to periodically cut the biostrips and blow the biomass material directly onto the adjoining beds as a mulch, or a green chop food source for soil microorganisms when rotovated under. In a wet year particularly, several cuttings are necessary. For tender leaf crops such as lettuce the mulch is blown onto the prepared beds first and the lettuce plugs transplanted through it. The lettuce matures before the strips need cutting again. Many crops from squash to tomatoes benefit from several mow and blow mulchings before fruit set. The biostrip grasses become less vigorous/more dormant later in the heat of midsummer and do not need much mowing -- allowing for the creation of a mature, biodiverse habitat for beneficials.

· Attention is paid to potential incompatibilities. Queen Anne's Lace may vector aster yellows to lettuce, for example, and is kept mowed before it develops anywhere near lettuce beds.

Once the soil fertility and biostrip habitat factors are integrated, this holistic system creates a synergistic natural reservoir of plant pest and disease protection while providing an ample supply of balanced crop nutrients. Nature itself is transformed from being viewed as a hostile force out to destroy and devour a farmer's crops, into a powerful and awesome ally. Conventional intervention thresholds no longer hold true or become necessary. The farmer too becomes an integral part of the whole system, privy to working with nature in a positive, creative and meaningful way.

Steve Gilman, Ruckytucks Farm, 130 Ruckytucks Road, Stillwater, NY 12170
518/583-4613 sgilman@netheaven.com

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References for Steve's comments:
Complete reference for Farmscaping from ATTRA:
http://www.attra.org/attra-pub/farmscape.html

Pickett, Charles H. and Robert L. Bugg, editors. 1998. Enhancing Biological
Control: Habitat Mangement to Promote Natural Enemies of Agricultural
Pests. Univ. of California Press.

Here's another useful reference from SARE:
Naturalize your farming system: A whole farm approach to managing pests
http://www.sare.org/farmpest/index.htm

Kim Stoner
University of Connecticut