Resources for Weeds

Title Available As Summary Date ID Author
Prevention and Control of Palmer Amaranth in Cotton
Palmer amaranth (Amaranthus palmeri), a member of the "pigweed" family, is one of the most troublesome weeds in many southern row crops. Seed can germinate all season and plants can grow to over 6 feet in height. Plants have either male flowers that shed pollen or female flowers that can produce up to 600,000 seed per plant. One Palmer amaranth per 30 foot of row can reduce cotton yield by 6 to 12%.
Mar 25, 2015 2805-1001 (PPWS-60NP)
Palmer amaranth (Amaranthus palmeri) Control in Soybeans Mar 20, 2020 2808-1006 (SPES-194NP)
Weed Management Update in Small Fruit Jul 24, 2009 2906-1328
Green Stem Syndrome in Soybean Dec 22, 2009 2912-1430
Water Garden Plants Sep 29, 2011 3109-1594
Fertilizing Cool-Season Forages with Poultry Litter versus Commercial Fertilizer Aug 30, 2019 418-142
The Nutritive Value of Common Pasture Weeds and Their Relation to Livestock Nutrient Requirements Aug 6, 2009 418-150
Exotic Invasive Plants
Invasive exotic species are plants that are not native to a given area and have the ability to out-compete indigenous plant species. Invasive exotics are often brought into their non-native surroundings by humans with good intentions.
Apr 29, 2020 420-320 (CNRE-105NP)
Successful No-Tillage Corn Production Mar 20, 2019 424-030
Poison Ivy: Leaves of three? Let it be! May 9, 2018 426-109 (HORT-292P)
Identification and Control of Annual Ryegrass in No-Till Corn in Virginia May 1, 2009 427-001
Control of Common Pasture and Hayfield Weeds in Virginia and West Virginia May 1, 2009 427-002
Itchgrass Identification and Control in Virginia May 1, 2009 427-008
Identification and Control of Common Reed (Phragmites australis) in Virginia May 1, 2009 427-101
Lawn Moss: Friend or Foe? May 1, 2009 430-536
Identification and Control of Honeyvine Milkweed (Ampelamus albidus (Nutt.) Britt.) in Virginia
A perennial with slender, twining stems that may reach 10 feet in length.
May 1, 2009 450-139
Identification and Control of Hemp Dogbane (Apocynum cannabinum L.) in Virginia May 1, 2009 450-140
Identification and Control of Mugwort (Artemisia vulgaris L.) in Virginia
Perennial weed with persistent rhizomes that may be spread or transported by cultivation equipment or also in burlaped nursery stock infested with rhizomes.
May 1, 2009 450-141
Identification and Control of Horsenettle (Solanum carolinense L.) in Virginia
A perennial from rhizomes with conspicuous spines on leaves and stems reaching 3 feet in height.
May 1, 2009 450-142
Identification and Control of Trumpetcreeper (Campsis radicans (L.) Seem ex Bureau) in Virginia
Perennial woody vine that may reach 40 feet or more in length.
May 1, 2009 450-143
Pest Management Guide: Field Crops, 2020 Feb 6, 2020 456-016 (ENTO-366P)
Pest Management Guide: Horticultural and Forest Crops, 2020 Jan 27, 2020 456-017 (ENTO-337)
Virginia Master Naturalist, Basic Training Course, Botany
Plants can be defined as multicellular, photosynthetic organisms with reproductive structures that are more complex than single cells. By this definition, algae are not considered plants because they are either unicellular or their reproductive structures are essentially unicellular. Fungi, too, are excluded because they are not photosynthetic. At least 400 million years of diversification have resulted in a wide diversity of taxonomically distinct major groups of plants. Some of the most important groups of plants found in Virginia are described below.
Jul 19, 2019 ANR-10NP (CNRE-62NP)
Weed Control in Hops
Because hops are long-lived perennials, controlling weeds near plants without causing injury can be challenging. Furthermore, empty spaces between rows can quickly become filled with weeds if left unmanaged. Growers therefore need a year-round weed management plan. An important part of that plan is identifying the common weeds at the site and understanding their life cycles. Once weeds have been identified, a management plan can be developed using cultural, chemical, or integrated approaches.
Mar 11, 2015 ANR-144NP
Sensor-Based, Variable-Rate Nitrogen Applications in Virginia
Variable-rate applications (VRA) of nitrogen (N) fertilizers are a new option to assist producers with real-time fertilizer rate decisions. Two commercially available systems that allow variable-rate nitrogen applications are GreenSeeker (Trimble Navigation Limited; www. and the OptRx Crop Sensor (Ag Leader Technology; www. A discussion of the science behind these systems, potential economic benefits, and other methodologies to make VRA is discussed in Virginia Cooperative Extension publication 442-505, “Precision Farming Tools: Variable- Rate Application” (Grisso et al. 2011).
Aug 8, 2014 CSES-90P
Integrated Pest Management of Hemp in Virginia Mar 2, 2020 ENTO-349NP
Weed Management in Small Fruit Crops Jan 23, 2018 HORT-286NP
Managing Troublesome Crop Weeds: Current Practices Jul 25, 2017 PPWS-101NP
Glyphosate Q & A Sheet Feb 8, 2019 SPES-113NP
Harvest Weed Seed Control May 6, 2019 SPES-135NP
Common Ragweed (Ambrosia artemisiifolia) Control in Soybeans Jun 6, 2019 SPES-143NP
Using Cover Crops to Suppress Horseweed Aug 21, 2019 SPES-164NP
Giant Hogweed: Identification and Control Jul 27, 2018 SPES-48NP
Control of Common Grassy Weeds in Pastures and Hayfields
Grassy weeds in pastures and hayfields compete with desired forage species and reduce the productivity of forage systems. Lack of selective herbicides makes grassy weed species, such as Johnsongrass, Japanese stiltgrass, broomsedge, and foxtail species difficult to control. Proper soil fertility, grazing management, and correct timing and placement of herbicide application can effectively control these species.
Nov 6, 2018 SPES-58P
Pesticide Applicator Manuals Nov 17, 2011 VTTP-2
Pyridine Herbicide Carryover: Causes and Precautions Sep 9, 2012 VTTP-6NP