Integrated Weed Management

Multi-fruit orchard spray program for the control of major tree fruit pests and diseases.

Starting clean or weed-free is the key to a good weed control program, especially when noxious weeds, such as Palmer amaranth are present. While conventional growers can use soil-active herbicides to manage these weeds, control is more complicated in organic systems. Flame weeding is a non-chemical tactic that has been shown to control several grass and broadleaf weed species.

The University of Maryland Pesticide Safety and Training program was created to assist agricultural producers and businesses with timely information regarding pesticide use and recommendations. Farms use Integrated Pest Management (IPM) to solve pest problems while minimizing risks to people and the environment.

This is a poster that provides the relative effectiveness of various integrated weed management tactics for summer annual crops. The chart helps identify the most effective tactics to manage weeds.

In last month’s issue of Agronomy News, I discussed considerations for glyphosate-based burndown programs. This month I wanted to share some of my results using similar programs to manage a rye (Fig. 1) and hairy vetch (Fig. 2) cover crop. Treatments were applied on April 11, and consisted of glyphosate, glufosinate, paraquat, glyphosate + 2,4-D, glyphosate + dicamba, glyphosate + glufosinate, and glyphosate + paraquat. Currently, this is what I am seeing:

It’s that time of year when growers are considering which herbicides to include in their burndown programs. Utilizing effective herbicides will help to ensure less weed competition at planting. However, growers should consider not only what herbicides they plan to use in their burndown programs, but also the weed species present in the field.

Poison Hemlock (Conium maculatum, Fig. 1), is a member of the plant family Apiaceae, which contains a few important crops such as carrots, celery, and parsnips. This weed is a tall, invasive, and highly poisonous weed that is sometimes mistaken for one of its crop relatives. It is also commonly mistaken for Queen Anne's Lace (Daucus carota).

Pros and cons of vinegar as an alternative to glyphosate

Mowing is a relatively inexpensive mechanical weed management option that imposes minimal disturbances to the soil. Several types of commercial mowers including rotary, flail, reciprocating sicklebar and reel can be used to suppress weed growth. Still, mowing is generally not thought of as a formable integrated weed management (IWM) tool as it is not congenial to most cropping systems or all land types. For instance, having a smooth soil surface free of rocks or other obstructions is a necessity for mowing operations, and if mowing close to the ground, the soil surface should be even. Some have declared that mowing is primarily used to limit seed production and restrict unsightly weed growth in un-tilled herbaceous and woody perennial crops.

Fruit and Vegetable News, Volume 12, Issue 7 (November 1, 2021)