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Crop Management

All Crop Management Content

A color-coded map of the United Statees showing the precipitation outlook for August through October 2019. All of South Dakota is light green. Parts of Western South Dakota are a darker green.

Wet Conditions Likely Into Fall Season

Many locations in South Dakota have already received as much precipitation this year as they do in an entire average year. The latest climate outlook from NOAA’s Climate Prediction Center shows increased chances of wetter than average conditions to continue into the fall season.

Small, green soybean aphids on a green, soybean stem with pink flower.

Small Populations of Soybean Aphids Observed in South Dakota

While scouting fields last week, we observed small populations of soybean aphids near Volga, South Dakota. Although no sustained populations were observed, it is a good reminder that soybean aphid scouting should occur throughout the growing season to prevent population outbreaks.

Symptoms of three common corn diseases. From left: anthracnose leaf blight, common rust and eyespot.

Is a Fungicide Needed for Developing Corn Diseases?

Corn is starting to tassel in several locations across the state. This is also the growth stage when a fungicide may be applied to control fungal leaf diseases. Diseases currently starting to develop are: anthracnose leaf blight, common rust and eyespot.

Three color-coded maps indicating no-till, conservation tillage, and conventional tillage percentages in South Dakota. For a complete description, call SDSU Extension at 605-688-6729.

Soil Conservation Practice Adoption Status at the S.D. County Level: 2012–2017

An increasing number of farmers across the state of South Dakota have adopted different soil conservation practices such as no-till, conservation tillage and cover crops. Over time, these practices play significant roles in improving soil health and increasing soil resilience towards extreme weather conditions.

A sprawling wheat field with gray, mostly cloudy skies in the background.

Small Grain Pre-Harvest Options

Consider pre-harvest herbicide applications in crop ground planted with small grains that are grown for seed or forage. Dense weed populations may inhibit harvest, therefore proper control of them early in the growing season is best.

Corn plants with noticable rotting near the bottom stem.

Fusarium Root and Crown Rot Developing in Corn

A few corn fields scouted in Brookings County were found with Fusarium root rot at low levels. Infected plants were wilting and upon splitting of the lower nodes revealed brown discoloration of the pith. Root and crown rots developing in corn after the seedling stage are usually caused by Fusarium spp. and can be enhanced by injury to the roots or crown, mainly by insect feeding.

Dark green and tan curled caterpillars with an orange stripe along their sides.

Watch for True Armyworms in Wheat

This week we observed some true armyworm caterpillars in winter wheat fields. The caterpillars were still relatively small, which means they will continue feeding for some time. So far, the true armyworm caterpillars were still feeding on the leaves of the nearly mature wheat, but they have the potential to also clip heads off of the plants.

Soybean leaves with several bright green lesions progressing into tears with brown crusting along the edges.

Bacterial Blight Common in Soybean Fields

Several soybean fields scouted the week of July 15, 2019 were found with bacterial blight developing. The frequent rains experienced in most soybean growing counties have led to the development of this disease. Bacterial blight affected leaves are most evident on younger leaves in the upper canopy.

Green wheat with many green stink bugs present on it.

Say’s Stinkbug Present in Western S.D. Wheat: Do I Spray?

While looking at winter wheat at the new SDSU West River Research Farm near Sturgis, we came across some very large stinkbug populations in a few areas of the field. The stinkbugs we observed were the Say’s stinkbugs. Although stinkbugs have the potential to reduce wheat yields, this is attributed with feeding that occurs between the late boot and milk stage.

Gray beetle with long antennae that are alternating white and black pattern on green leaf petiole.

Dectes Stem Borer Adults Active in Sunflower

In South Dakota, one of the insects that is commonly observed in sunflower is the Dectes stem borer larva. At this point in the season, adults are beginning to become active with females laying eggs in sunflower plants.