Using Chickens and a Cover Crop Barrier for Weed Control in Organic Asparagus

Project Overview

Project Type: Farmer
Funds awarded in 2009: $7,175.00
Projected End Date: 12/31/2011
Region: Northeast
State: Maine
Project Leader:

Annual Reports


  • Vegetables: asparagus


  • Pest Management: weeder geese/poultry
  • Production Systems: organic agriculture

    Proposal summary:

    Current issue

    Chick Farm is a small diversified farm producing eggs, meats, and a wide variety of certified organic vegetables for our CSA program and a wholesale account. For some time now we have wanted to establish a “cash crop”, something we could grow on a larger scale to make our operation more profitable. Organic asparagus is a high-value crop that grows well in the Northeast and is well-suited to our sandy soil. We have been hesitant, however, to invest the time and money needed to establish a sizeable asparagus planting, given that weed control – a significant challenge for any organic crop – is especially difficult for a perennial such as asparagus.

    A case in point is our existing asparagus bed, a small (200 row ft) planting which over the years has become very weedy despite our efforts to control weeds mechanically and with mulch. In 2008 we tried a new approach: once the asparagus harvest was over and the plants had ferned out, we used our newly constructed “chicken tractor” (a portable chicken shelter) and a moveable fence to let 30 laying hens forage in the asparagus patch from early August until mid-October. Given how well-entrenched the weeds were, we didn’t expect the chickens to completely eliminate the problem, but they did make significant progress with no apparent harm to the asparagus plants. Based on this experience, we propose to study the effectiveness of using chickens and a cover crop barrier to control weeds in organic asparagus. The results of this study should be of interest to other organic growers who already grow asparagus or would like to establish an asparagus planting.

    Project objectives from proposal:

    This project will evaluate the effectiveness of controlling weeds in organic asparagus with the use of chickens and a cover crop barrier. Organic asparagus is a high-value crop that grows well in the Northeast, but weed control is a significant challenge, particularly because asparagus is a perennial crop. We propose to evaluate a two-pronged approach: first, after the asparagus harvest season is over, we will allow laying hens to range freely in the asparagus patch by using a “chicken tractor” (a portable chicken pen) and a moveable fence. Our experience with this technique on a small scale leads us to believe that the chickens will do a good job of controlling both grasses and broadleaf weeds. The second experimental technique is to establish a “weed barrier”, a tilled buffer zone 10 feet wide around the perimeter of the asparagus patch. This buffer zone will be planted to a cover crop (oats or winter rye) every fall to help keep perennial weeds (such as quack grass, Agropyron repens) from working their way into the asparagus from the surrounding sod.

    We will gather data on weed intensity and on the growth and yield of the asparagus, in the experimental planting and a control planting. We will also compare the use of two types of organic mulch (straw and waste hay), determine guidelines for the recommended number of chickens per acre, compare insect pressure between the two plots, and evaluate different methods for incorporating the winter rye cover crop in the spring.

    We will share our results with other farmers through an article in the Maine Organic Farmer & Gardener and by giving talks at the Maine Department of Agriculture Trade Show and at an event sponsored by the UNH Cooperative Extension Service.

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.