Skip to main content

Forage

All Forage Content

Smart to Lead SDSU Extension Agriculture and Natural Resources Program

July 06, 2021

South Dakota State University Extension has named Alexander “Sandy” Smart as the new Agriculture and Natural Resources Senior Program Leader.

Two mites. From left: Green leaf with two yellow spider mites with dark spots. Green leaf with yellow spider mite.

Spider Mites Reported in South Dakota Crops

With drought conditions continuing in South Dakota, it isn’t surprising that two-spotted spider mite infestations are being reported throughout the state. With hot temperatures in the forecast and limited chances for precipitation, we can expect spider mite populations to thrive in infested fields.

Dark-colored aphids on a green stem.

Cowpea Aphids Infesting Alfalfa

Typically, we worry about pea aphids in alfalfa. However, we noticed that cowpea aphids were present on alfalfa this week. If left unmanaged, cowpea aphids can stunt alfalfa, reduce yields and even kill the plants during severe infestations.

Alfalfa plant that has numerous holes in the leaves.

Keep Scouting for Alfalfa Weevils

This week we received a report and picture confirmation of early-instar alfalfa weevil larvae in an alfalfa field. Although most alfalfa fields were treated for alfalfa weevils before the first cutting, those fields still need to be scouted.

Small, pale-green leafhopper on a green alfalfa leaf.

Start Scouting for Potato Leafhoppers in Alfalfa

Potato leafhoppers are a migratory pest that commonly impact alfalfa fields throughout South Dakota. They cannot tolerate our cold winter temperatures, so they travel up from the southern United States each spring.

Three beetles. From left: Black colored blister beetle on a purple flower. Gray colored blister beetle on a green alfalfa stem. Orange-brown colored blister beetle feeding on a sunflower head.

Blister Beetles Showing up in Alfalfa Fields

Blister beetles are now active in South Dakota. Although the larvae of blister beetles can be beneficial by feeding on grasshopper eggs, the adults cause issues when large populations are present in alfalfa at the time of harvest.

patch of reed canary grass in pasture

Reed Canary Grass: Possible Prussic Acid & Alkaloid Issues

Prussic acid issues with reed canary grass are poorly understood and may go unrecognized if they occur. This article addresses a little-known but interesting aspect of the biology of reed canary grass.

White and red caterpillar feeding within silken hideout on green soybean leaf.

Thistle Caterpillars Observed on Canada Thistle

Although thistle caterpillars are normally first observed in July or August, it is possible for them to appear earlier if weather conditions are favorable. While these caterpillars are generally not present in high numbers, they can cause severe defoliation.

Rangeland covered with dense thickets of maturing cedar trees.

Cedar Trees and Rangeland Loss

The issue of cedar tree invasion into South Dakota’s rangelands tends to be a regional conversation. There is generally broad agreement among most resource professionals that these trees are in fact changing our landscape in a negative way.

Herd of cattle swath grazing hay in a winter pasture.

Swath/Bale Grazing

Swath grazing and bale grazing are harvest systems that mesh haying and grazing techniques. Generally, the objective is to reduce labor and equipment expenses by allowing livestock to consume the hay crop in the field.