Farmscaping and biological control
By Lynn Byczynski
Farmscaping is a new term for an integrated, whole-farm approach to biological control of pests. It involves laying out the farm to include hedgerows, insectary plantings, cover crops, water, and other features to attract and sustain beneficial organisms.
Beneficials, including insects, bats, birds, and microorganisms, can be powerful allies in a sustainable farm system. They can reduce pests to tolerable levels without the use of pesticides, which in turn improves farm worker health and the safety of farm products.
Biological control requires more knowledge and management than conventional pest control. The grower must learn the life cycles of pests, the types of beneficials that control those pests, and the kinds of plantings that harbor the desired beneficials. There is also the risk of harboring pest insects if farmscaping efforts are inconsistent or poorly planned.
Biocontrol includes these strategies:
- Removing overwintering habitat or other sources of pests.
- Establishing insectary plantings, which can be perennial hedgerows and/or annual strips in the field.
- Releasing purchased beneficial insects when needed.
- Planting trap crops to lure pests away from cash crops.
- Scheduling crops to avoid high pest populations.
- Building nest boxes for birds and bats.
For more information, read the article “Farmscaping: Making Use of Nature’s Pest Management Services.”
Several federal conservation programs may provide cost share for farmscaping programs. To learn more about planning and funding farmscaping, see the ATTRA publication “Farmscaping to Enhance Biological Control". Article costs $2.95 to download.
By Lynn Byczynski
Beneficial insects need food and shelter if they are to control pests of vegetable, flower, or herb crops. An insectary planting of flowering plants will greatly increase the likelihood that predators and parasitoids will hang around and help with pest management. An insectary planting can be reserved entirely for beneficials, or it can be small, unharvested areas of valuable crops such as flowers and herbs. Here are some of the plants that can be used:
Cover crops. Many plants grown to improve soil fertility and tilth are also attractive to beneficial insects when they are allowed to flower. Buckwheat is one of the best, especially because it flowers over a long period. Other cover crops that provide food and shelter for beneficials include the clovers, hairy vetch, cowpeas, and alfalfa. Growing cover crops in numerous small sections throughout a field keeps the beneficials close to the cash crops.
Grasses and grains. Often grown in strips among cash crops, grasses and grains provide refuge for ground beetles and spiders and a shady place to lay eggs for other beneficial species.
Flowers and herbs. Several families of flowers are particularly attractive to beneficials. The Apiaceae family has umbels of tiny flowers that are a good source of nectar. It includes angelica, Ammi majus, anise, carraway, carrot, cilantro, dill, fennel, parsley, Queen Anne’s lace, tansy, and yarrow. The Asteraceae family provides abundant and easily accessible pollen. Many cut flowers are in this family, including sunflowers, blanket flower, coneflower, cosmos, and goldenrod.
Vegetables. Mustard-family vegetables, including many Asian greens, broccoli, cabbage, kale, mustard, and turnips, can be left to flower for beneficials.
Trees and shrubs. Permanent hedgerows provide refuge for many types of beneficials and will be especially attractive if they include black locust, elderberry, euonymus, and Prunus species.
A helpful resource is the publication “Practical Guidelines for Establishing, Maintaining, and Assessing the Usefulness of Insectary Plantings On Your Farm.”
By Lynn Byczynski
A good supply of hay is a great advantage on a vegetable farm. Hay can be used for moisture-conserving and weed-suppressing mulch, added to a compost pile to balance C:N ratios, and fed to livestock in winter. Because of its many benefits, and the expense of purchasing hay, growers often wonder whether they should grow their own.
Points in favor of growing hay:
- You can be sure it is not contaminated with herbicides, some of which can kill vegetable crops and carry over for more than a year.
- You can ensure that it has high-quality nutrition and is free of mold and pests. You don’t have to haul it from another farm or pay for delivery.
- You can save a lot of money compared to buying hay, assuming you already own the necessary equipment and storage space. Land that is not needed for crops can be put to good use.
- Haying prevents the establishment of woody plants that you would otherwise need to control in fallow fields.
- As part of a rotation, a legume/grass pasture will contribute nutrients and organic matter to the soil.
- You can graze livestock on your pasture as well as cut it for hay.
- The smell of new-mown hay is one of the sweetest fragrances in the world.
Points against growing hay:
- The work of mowing, raking, baling, and moving hay may occur at your busiest season for vegetable crops.
- You may need to buy, rent, or borrow the appropriate equipment.
- You may need to spread manure before planting, if a soil test indicates it.
- You will have to learn about when to cut and how to test moisture before baling.
- Establishment costs can be high for a large area.
- You may have to hire extra help to get the baled hay into the barn.
After weighing the pros and cons, you should talk to local experts including your Extension agent and neighboring farmers to determine what pasture mix is best for your climate and soil type. The purpose of the hay, whether it’s for livestock feed or mulch, will also determine which species to plant. A grass/legume hay meadow can produce for as long as seven years, so research your options carefully before you get started.
A good discussion about growing hay for your own use or as a business can be found on the Sheep’s Creek Farm website.
A sustainable farm seed plan
By Lynn Byczynski
Be self reliant and grow your own inputs. Reduce the purchase of fertilizers, animal feed and hay mulch by growing much of your own. You'll save money and improve the health of your livestock, soils, crops, and, ultimately, the food you sell and eat. Johnny's Farm Seeds can contribute to a sustainable plan by offering:
Pasture mixes of grasses and legumes provide an important source of food for livestock. Organic certification requires that ruminants such as cattle, sheep, and goats have access to green pasture during the growing season. Grazing also benefits non-ruminants, reducing the amount of other feed required as it improves health.
Hay and silage can be grown on the farm to provide feed for livestock during the winter. Forage turnips can provide feed for livestock even when covered with snow. Growing your own feed reduces the need to buy hay, an expense that can significantly reduce the profit potential of livestock.
Grains are essential to the diets of poultry and swine. Most cattle also are fed grains. Growing and mixing your own feed rations may be more cost-effective and even necessary for certified growers if local certified-organic feeds are not available. At home, grains can be milled for baking and Royal Hybrid 1121 produces delicious edible sunflower seeds and bird food.
Farmers without livestock face the perennial challenge of renewing soil fertility for vegetable crops. They depend on green manures; cover crops that provide nutrients, increase organic matter, and improve soil tilth. Johnny's carries over 20 varieties to fit your specific needs.
Hay meadows can be cut and baled to provide mulch for vegetable crops, thus reducing the need for petroleum-fueled tillage.
Insectary plantings help to increase pollination of vegetable and fruit crops while providing nectar and habitat for beneficial insects. Certain crops such as oilseed radish and mustards control nematodes while also increasing soil organic matter. Many growers include insectary plantings as part of their overall sustainable practices plan.
The Advantages of Cover Crops
Cover crops are an essential component of every sustainable farm. They are
an investment in your gardens and fields that will pay future dividends of healthier,
more productive cash crops.
The benefits of cover cropping are numerous and impressive:
- Cover crops increase soil fertility. Annual legumes such as soybeans and cowpeas can be grown in rotation over several years in vegetable fields. Perennial legumes such as clovers can be maintained for several years on fields that aren't needed for cash crops. Legumes fix nitrogen while they're growing, and add organic matter when incorporated into the soil.
- Cover crops used for this purpose are referred to as "green manures."
- Cover crops prevent soil erosion in winter by keeping the soil covered. A mixture of oats and winter rye, for example, can be planted in fall. The oats will be killed by cold weather, but their root systems will hold the soil in place. Winter rye will form small plants that will grow rapidly in early spring, to be mowed and tilled in before planting the field the following summer.
- Cover crops prevent weeds from flourishing on bare soil, in which case they are known as "smother crops". Fast-growing annuals such as buckwheat or soybeans can be planted after a crop is harvested to outcompete weeds. They also can be underseeded with taller cash crops or between rows to cover the soil and prevent weed growth.
- Cover crops can be planted as a "catch crop" after a vegetable crop is harvested to use nutrients that might otherwise leach into groundwater.
- Cover crops improve soil tilth. Besides adding organic matter when tilled in, the roots of actively growing cover crops loosen and aerate soil. Deep-rooted cover crops such as sweet clover will help break up hardpan layers several feet deep. Several cover crops can be grown to be cut for hay or straw, to feed livestock or mulch horticultural crops.
Quick cover crop for weed control
By Lynn Byczynski
Buckwheat is one of the easiest and quickest cover crops, used primarily to suppress weeds and improve soil tilth. It is a warm-weather crop that can be used between spring and fall vegetables or in preparing new ground - when planted on newly prepared sod ground, buckwheat will help rot down the sod - for vegetable or berry production in fall or the following year.
Buckwheat is an attractive plant, 2' to 4' tall with triangular leaves and flowers of white, pink, or red. Buckwheat germinates within days of seeding and does best at a soil temperature of at least 55F/12.8C. It begins to flower in four weeks and is a source of nectar for honeybees and native pollinators. Seed matures two to three weeks after flowering and, if left in the field, is a food source for ground-dwelling birds such as quail and pheasant. Buckwheat will be killed by light frost. It does not provide nitrogen nor does it increase soil organic matter significantly, but it does improve soil condition in the top few inches, a benefit for vegetable seeds and transplants.
The key to using buckwheat for weed control is to provide the optimum conditions for getting it up and growing so that it will be ahead of weeds. Here are some tips for getting a strong stand and managing it for improved vegetable production in the future:
- Till in any weeds or plants from a previous crop and wait one week for the debris to decompose sufficiently for the buckwheat seed to germinate. Break up big clumps of soil, and create the finest seedbed possible.
- Let the soil warm up and dry out if it's been wet. Buckwheat seed rots easily in cold, wet soil. If the soil is extremely dry, irrigate to a depth of 1" before planting.
- Buckwheat seed should be barely covered with soil for best germination. Do not plant too deeply, but don't leave the seed exposed on the soil surface either. Buckwheat seed can be hand-broadcast at a rate of 60 lb. per acre if care is taken to spread it evenly. Or it can be drilled to a depth of less than 1 inch at a rate of 50 lb. per acre. If there is heavy weed pressure or you are planting organic buckwheat seed, you may want to increase the rate to about 80 lb. per acre.
- As the seed germinates, check for gaps in the stand, and reseed any that are more than 1' in diameter. If weeds are allowed to grow in these empty areas, they will produce seeds that continue the weed cycle, and the benefits of the buckwheat will be reduced.
- The plants should start to flower about four or five weeks after seeding. If the land is needed for a fall crop, mow the buckwheat before the seeds mature. If the land won't be needed until the following year, the buckwheat can be left to reseed and a second crop can be grown in the same season. However, buckwheat will not overwinter, so it should be mowed and replaced with a winter cover crop in late summer or fall.
For more information
• Oregon Cover Crops: Buckwheat by Oregon State University Extension
• Cover Crop Database: Complete Crop Summary of Buckwheat by University of California Sustainable Agriculture Research and Education Program
• Buckwheat Cover Crop Handbook from Cornell University
By Lynn Byczynski
Winter is a good time to be working on soil improvement, and you don't have to go out in cold weather to do it. By planting a cover crop in summer or fall and letting it overwinter, you can improve soil organic matter and soil fertility, suppress cool-season weeds, prevent soil erosion, and create a better seedbed for spring planting.
The best winter cover crops vary by region, depending on the crops' winter hardiness, but from a management perspective there are basically two types: crops that are killed by cold but have enough biomass to protect the soil and those that remain alive through winter and resume growth in spring.
Oats are an example of the first type. Sown in summer, they will put on a lot of growth before being killed by heavy frost. The killed mulch and root mass will hold the soil in place until the following spring. Other plants that may be grown for winterkilled mulch include field peas, oilseed radishes, and rapeseed. The disadvantage to this type of cover crop is that you have to clear the land and plant the cover crop early enough to get significant amounts of biomass to hold the soil over the winter. That could mean cover-cropping only on ground that grew spring vegetables, or it could require undersowing the cover crop in a summer crop such as corn. The big advantage of a winterkilled cover crop is that the mulch is easy to till under in spring and the land can be planted right away.
Cover crops that live through winter, or that go dormant and renew growth in late winter, can usually be planted after summer vegetable crops. They will grow in fall and establish root systems that protect the soil over winter. Some examples of crops that will survive winter (depending on winter low temperatures) include winter rye, winter wheat, hairy vetch, Austrian winter peas, and crimson clover. Winter rye and hairy vetch are recommended for the northern United States. In regions where these crops survive winter, they will grow vigorously in early spring. They will need to be mowed close to the ground to stop growth and then incorporated into the soil. Because decomposition of the cover crop debris will tie up nitrogen, it's a good idea to wait two or three weeks before planting.
Many growers use a mixture of cover crops from the two categories. Johnny's Fall Green Manure Mix is a blend of winter rye, field peas, ryegrass, crimson clover, and hairy vetch. The peas, clover, and ryegrass are winterkilled. The rye and hairy vetch regrow in spring.
• Winter Cover Crop Chart by Pam Dawling in Growing for Market, September 2009
• Overview of Cover Crops and Green Manures by ATTRA, the National Sustainable Agriculture Information Service
• Cover Crops and Living Mulches, Sustainable Practices for Vegetable Production in the South
• Improve Your Soil with Cover Crops by Cornell University
By Lynn Byczynski
Many farmers grow mixtures of cover crops to multiply the benefits of a planting. The most common approach is to grow legumes and grasses together. Some popular combinations include hairy vetch or red clover plus winter rye in cold winter areas or bell beans plus oats in milder winter areas. A legume-grass combination offers several benefits:
- Legumes and grasses grown together balance the carbon-to-nitrogen ratio in the soil after plow-down. The legumes, rich in nitrogen, break down quickly while the carbon-rich grasses take longer to decompose. Growing the two together makes nitrogen available to help break down the grass residue and reduces the amount of time that must elapse before a subsequent crop can be planted.
- A faster-growing crop such as oats or winter rye serves as a nurse crop to shelter less-robust, slower-growing plants such as red clover or sweet clover. Grasses establish quickly and prevent the growth of weeds that would otherwise compete with the legume.
- Low-growing crops and taller crops planted together cover more of the soil and do a better job of preventing erosion and weeds. Sorghum grows tall, and cowpeas grow low; together they shade the soil and prevent weed seeds from germinating.
- Legumes increase nutrient content of a hay crop that is to be used for livestock.
- Combinations of cover crops reduce the risk of crop failure and allow for differences in conditions across a field. In spots where a legume doesn't establish well, the grass may do better and vice versa.
• An Introduction to Cover Crop Species for Organic Farming Systems from the eOrganic network.
• Overview of Cover Crops and Green Manures by ATTRA, the Sustainable Agriculture Information Service.
Lynn Byczynski is the editor of Growing for Market, a magazine for local food producers.