Cover Crops for Weed Management
Cover crops are well-known for their soil health benefits however, their ability to suppress weeds is not fully known. High-residue cover crops have the potential to suppress winter and summer annuals. Research efforts are currently focused on suppression of Palmer amaranth and other problematic weeds and examining rolled versus not rolled cover crops and planting green versus brown.
Harvest Weed Seed Control
Harvest weed seed control (HWSC) is a newer weed management practice that focuses on destroying seeds that will become weeds in future seasons with harvest operations. Research efforts here are aimed at comparing different types of HWSC to control three major weeds in Virginia: Palmer amaranth, common ragweed, and Italian ryegrass.
Herbicide Resistant Weed Management
Herbicide resistant weeds are a serious threat to agricultural productivity in Virginia. The instance of herbicide resistance is only projected to increase. Documenting cases of resistance in the Commonwealth and developing best management practice is a large research effort of the lab. Best management practices against resistance are rotation of herbicide mechanisms-of-action, rotation of herbicide-tolerance seed traits, implementation of integrated weed management strategies such as cover crops or harvest weed seed control, and evaluation of alternative herbicide options.
Virginia Weed Identification Clinic
The Virginia Weed Identification Clinic is housed within the Flessner Lab but is a collaborative effort between all of the weed scientists at Virginia Tech. The goal of the Clinic is to identify and offer control and management recommendations for unknown weed species sent in from throughout the Commonwealth. The Weed Clinic has been in operation from 1985 and has identified over 8,500 plant samples from every county and independent city in Virginia. Over 1,000 unique species have been sent to the clinic in the past decade. Growers and homeowners can submit unknown plant samples through their local extension agent. Instructions can be found at here.
Virginia Tech Weed Identification Website
There is a new VT Weeds website available. The original VT Weeds site was among the first of its kind and has become a wonderful resource for the industry. We are excited for the progress being made on this site and will continue to add new species profiles to the website.
Pest Management Guide
Dr. Flessner is part of a collaborative effort put forth by a team of weed scientists that assemble and revise recommendations for weeds in field crops. Recommendations are based on herbicide efficacy testing. The Field Crops Guide is freely available for download or is available at your local extension office.