Although they are sometimes necessary for pest management, agricultural disturbances should be minimized to avoid disrupting the beneficial relationships and processes that ecological strategies build. Think of ways to reduce excessive tillage. This can be done by adopting conservation tillage options like no-till, strip-till and ridge till, as well as by reducing the frequency of tillage. Switching to a less disruptive implement like a chisel plow instead of a moldboard plow is another way to reduce soil disturbances. In no-till settings, growers typically rely on residual and pre-emergent herbicide applications to keep weeds low, but this encourages herbicide-resistant weeds to develop. Combine no-till with high-biomass cover crops like cereal rye to ease the pressure of herbicide-resistant weeds. Integrate grazing, wherever feasible, to manage weeds in reduced-till and no-till fields.
The SARE bulletin Cover Crop Economics provides a detailed explanation of how a cereal rye cover crop can pay for itself within the first two years when used to manage herbicide-resistant weeds. When the cereal rye produces enough biomass to smother weeds, growers can get by with fewer applications of lower-cost residual and post-emergent herbicides.
Pesticides are often another source of disturbance on the farm. They reduce biodiversity by destroying non-crop vegetation, which is an important overwintering site for beneficial organisms. They may also kill non-target insects that are beneficial or that serve as alternative prey to important natural enemies. Consider strategies like perimeter trap cropping, where you surround the perimeter of a crop field with another, more attractive variety that lures problem pests away from the cash crop. Target the trap crop border with a selective pesticide to kill the target pests and reduce the total volume of pesticide applied.
Project Highlight: Trap Cropping
In muskmelon production in Iowa, a combination of perimeter trap cropping and delayed row cover removal (LNC13-350) showed promise for managing cucumber beetles and the bacterial wilt pathogen that these beetles transmit. Researchers found that a two-row perimeter of the more attractive buttercup squash lures colonizing cucumber beetles away from the muskmelon cash crop. Applying an insecticide to only the trap crop reduces the overall amount of insecticide used by 59% and maintains effective insect and disease suppression. Learn more about the project and about perimeter trap cropping in the project webinar.
Table of Contents
- Part One: An Ecological Approach to Pest Management
- Part Two: Applying Ecological Principles to the Farm
- Diversify Plants and Animals Within Agroecosystems
- Grafting and Selecting Resistant Varieties
- Weed Control with Sheep
- Include Natural and Semi-Natural Habitats on the Farm
- Enhance Natural Enemies
- Manage Soil to Produce Healthy Crops
- Minimize Agricultural Disturbances on the Farm
- Create Multiple Stresses for Pests
- Reduce Excess Sources of Nitrogen
- As a Last Resort, Use Targeted Attacks
- Taking Stock: The Basics of Crop Scouting
- Beyond Pest Management