Resources for Weeds
|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. ntechindustries.com/greenseeker-home.html) and the OptRx Crop Sensor (Ag Leader Technology; www. agleader.com/products/directcommand/optrx/). 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|