Forage: Weeds, Disease, and Pest Management

Regardless of whether it is a tall fescue and legume pasture, a bermudagrass hay field or an alfalfa hay field; most annual and perennial broadleaf weeds reduce forage yield, palatability and quality. This is particularly true if heavy populations are not controlled on a timely basis and are allowed to reach maturity. In a pasture they also reduce grazing efficiency, which means cattle spend more time picking through and around weeds looking for grass and less time eating. The bottom line is that unmanaged weeds are one of several things contributing to lower forage and animal production. This section of our website will address weed management topics related to forage production, stewardship, pests, and methods for control of invasive species.

Use our guide with basic information on regional poisonous plants which can be harmful to livestock. Learn to recognize common poisonous plants and immediately contact a veterinarian if poisoning is suspected.

Information and Resources


Disease and Pest Control

Link Pointer Insect Control Recommendations for Field Crops
An Integrated Pest Management (IPM) program in Tennessee integrates control tactics including cultural practices, variety selection, biological control and insecticides to manage insect pest populations so that economic damage and harmful environmental side effects are minimized. Insecticides should only be used on an as‐needed basis; therefore, insect scouting must be conducted regularly throughout the season to determine if an insecticide application is warranted.

Link Pointer Bermudagrass Stem Maggot
The bermudagrass stem maggot is becoming a troublesome insect in bermudagrass
pastures and hayfields across Tennessee. This insect was first noticed in Georgia in 2010, although it is native to south Asia. The damage from this insect occurs at the last node of the stem where the leaf emerges.


Weed Management

Link Pointer Weed Control Manual for Tennessee
This manual contains The University of Tennessee weed control recommendations for corn, grain sorghum, cotton, soybean, burley and dark tobacco, wheat, forage crops, and farm ponds. These recommendations are based on results of research and demonstrations conducted by UT AgResearch and UT Extension. Decisions regarding recommendations are made by The University of Tennessee Weed Control Committee and are based on three years of data at various locations in the state.

Link Pointer Weed Control Strategies to Maximize Cool-Season Pasture Productivity
Key insights include the importance of early scouting to manage weeds before they bloom, and the effectiveness of using a mix of control methods. Implementing preventive and cultural practices not only boosts forage quality and yield but also reduces bare ground, saving on herbicides, labor, and fuel. A proactive approach leads to healthier pastures and a more productive system overall.

Link Pointer A Simple Method to Calibrate Sprayers
Before you can accurately apply the right amount of herbicide to a field, you have to know how much spray mix is being applied to each acre.

Link Pointer Competition Control in Native Warm-Season Grasses
Native grasses planted for forage production in the mid-South must compete with unwanted weeds and grasses. When that competition impacts stand vigor, quality, longevity or production, it should be controlled. Although some competition is inevitable, there are several steps you can take to minimize it.


Weed Fact Sheets

Link Pointer Arrowleaf Sida/Prickly Sida
Arrowleaf sida, also known as ironweed (not to be confused with tall ironweed) is an erect, summer annual herb. Prickly sida, also an erect, summer annual herb, is more commonly known as false-mallow, Indian mallow, spiny sida or teaweed. Both arrowleaf and prickly sida are members of the mallow (Malvaceae) family and are native to North America.

Link Pointer Nodding Spurge
Nodding spurge is an erect, summer annual herb that is a member of the family Euphorbiaceae. It is closely related to, and often confused with, spotted spurge, Chamaesyce maculata (L.) Small. This native of North America occurs throughout Tennessee; it is a troublesome weed in row and vegetable crops, ornamental, rights-ofway, pastures and hay fields, and many other situations.

Link Pointer Johnsongrass
Johnsongrass, Sorghum halepense (L.) Pers., is a member of the grass or Poaceae family. Johnsongrass is a very troublesome weed, as it is capable of extensive seed production and can propagate from creeping, thick rhizomes.

Link Pointer Horsenettle
This native of southeastern North America is found throughout Tennessee; it is particularly troublesome in grass pastures and hay fields. As is the case with most other weeds, prevention is an important component of an overall management plan.

Link Pointer Poison Hemlock
Poison hemlock, also called deadly hemlock, poison parsley, spotted hemlock, and California fern, is a highly poisonous biennial weed that is a member of the family Apiaceae, which is also referred to as the carrot family.

Link Pointer Tumble Mustard
Tumble mustard, also known as tall hedge mustard, Jim Hill mustard, and tall rocket, is a winter annual or biennial member of the Brassicaceae or mustard family.

Link Pointer Tall Ironweed
Tall ironweed is an erect, warm-season perennial plant that is a member of the sunflower family (Asteraceae). It is native to North America and can be found throughout Tennessee in hay fields, pastures and roadsides, particularly in moist areas.

Link Pointer Knotroot Foxtail
Knotroot foxtail is a warm-season perennial grass that is also known as knotroot bristlegrass or simply perennial foxtail. It is native to the Americas and can be found throughout Tennessee in hay fields, pastures, lawns, roadsides and waste sites.

Link Pointer Buckhorn Plantain
Buckhorn plantain, also known as English plantain, narrow-leaved plantain, and ribwort plantain, is an erect cool-season perennial plant that is a member of the plantain family (Plantaginaceae).

Link Pointer Buttercups
Several species of buttercup are found in Tennessee. Two of the most common are hairy buttercup and bulbous buttercup. They are not native to the United States and are members of the buttercup family (Ranunculaceae).

Link Pointer Chinese Privet
Chinese privet, also called privet, privet hedge, and hedge bush, is a woody, very invasive shrub native to China. It was introduced into the United States in the early to mid-1800s as an ornamental plant; it later escaped from cultivation and has naturalized throughout the southeastern United States.