Green Horizons

Alley cropping: Farming between the trees

By Gene Garrett | Sr. Outreach Specialist
W. (Dusty) Walter | Dir. Res. Mgmt, MU AES
Larry D. Godsey | Asst. Prof., Agri-Business, Mo Valley College

Photo courtesy of Dusty Walter

Alley cropping shown at work with this 40-foot alleyway.

Alley cropping, one of the five temperate zone agroforestry practices, requires the planting of trees at wide spacings creating alleyways within which companion crops can be grown. Companion crops can be conventional (e.g., corn or soybeans) or unconventional (e.g., biomass for energyor elderberry for jellies and wine). They can be a crop of high economic value (e.g., blueberries) or one of low economic but high aesthetic value (e.g., tall grass prairie for quail and other wildlife). Alley cropping can serve to transition fields of row crops into forests or, because of its desirable stewardship qualities, can be viewed as a standalone practice designed to provide a source of income, conservation and environmental benefits.

The early history of alley cropping has its roots in Southeast Asia. During the early 19th century, the Taungya System of forest management was developed by the British in Burma. In exchange for tending their Teak plantations, the wealthy allowed the poor the opportunity to grow food crops between and alongside their trees. Beginning in the 1960s and 1970s, a few visionaries began to speak out on the benefits of growing trees and food crops together to address hunger and ecological degradation in many parts of the world.

SAVE THE DATE

Allen Research and Education Site Field Day, April 11, on Old Eight Rd. off Rt. O, Laurie, Mo. The 2015 Field Day will be the first of many held on this highly diverse 560-acre farm. Agroforestry, forestry, wildlife, and warm-season grass management will be illustrated and discussed. Topics will include timber stand improvement (TSI), shiitake mushroom culture, "hack and squirt," chain saw safety, forest farming with botanicals, "feathering" for wildlife benefits, and more. Weather permitting, a warm-season grass burn will be conducted. Directions and other information will be posted on the UMCA website-centerforagroforestry.org

It was at this time that the Center for Agroforestry at the University of Missouri began research on alley cropping with black walnut. The initial plantings, which created 40-foot alleyways, proved too narrow to maximize the production opportunities, but much was learned.

Today's recommendation is to establish 40- to 50-foot alleyways only if the landowner is planning to transition from crops requiring full sun to crops more shade tolerant or transition from cropland to forest land, within an 8- to 12-year period. Under conditions where sun-loving plants (corn, soybeans, sunflowers etc.) are to be grown for longer periods, alleyways that are 60 feet or greater in width should be considered. Furthermore, to maximize the light reaching the alleyway crops, tree rows should be oriented east and west. Alley cropping is at its best when the species of choice offers high income opportunities while providing a suitable microenvironment within which companion crops can be grown. Specialty crop trees such as those that produce edible crops (Chinese chestnut, walnut and pecan) or long-needled pines (in Missouri - loblolly, pitch X loblolly hybrid, etc.) for the production of pine straw used as a landscaping mulch, are good examples. Yields of as high as 2,000 pounds or more per acre can be expected from Chinese chestnuts with a market value ranging from $1.50 to $7 per pound. Pine straw yields per acre will range from 150 to 250 or more 30-pound bales every other year, with a value between $4 and $7 per bale wholesale. When tree species that produce an annual or biennial crop are matched with the appropriate companion crop, alley cropping can become a practice of great economic value. (Portions of this article first appeared in "Inside Agroforestry" Vol. 19 Issue 2, 2011)