Grasses Weeds

Weed management is more challenging in organic crops and accounts for a large portion of production costs. As such, managing weeds is a major economic constraint to the organic vegetable industry, and comparisons of weed communities between conventional and organic farming systems consistently demonstrate higher weed levels in organic systems.

Biosolarization, akin to solarization, is a soil disinfection technique but involves the addition of organic amendments before the passive solar heating process. As the damp soil warms, organic materials break down, releasing allelochemicals and other biotoxic compounds briefly into the soil. Read more about "Evaluating Biosolarization as a Weed management Tactic in Organic Vegetables."

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.

Pros and cons of vinegar as an alternative to glyphosate

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:

Controlling Italian ryegrass, the potential causes of control failures following glyphosate applications, and useful tips for managing the species.

Understanding Preemergence Herbicides for Common Weeds in Vegetables

Organic Weed Control in No-Till Vegetable Systems

Japanese stiltgrass is an invasive grass that is typically seen in wooded areas. It likes shaded, wet areas and can easily take over the forest understory. Unfortunately, it can also creep into pastures and hay fields. The leaves of Japanese stiltgrass are wider and shorter than most of our common pasture grasses. There is also a distinctive silvery midvein that is slightly off-center from the middle of the leaf (Figure 1).