University of Missouri Extension

Barton County

September 2011 Crop Scouting Reports

Field Scouting Report for September 28…

Soybeans Maturing, Podworms Continue to be Problem

Brie Menjoulet, an agronomy specialist with University of Missouri Extension, scouted soybean fields around Golden City and Lockwood on Sept. 26.

Menjoulet report that in the area scouted, early planted soybeans are reaching maturity stages from R7 to R8. Double-cropped beans were still in the R6 seed development stage.

“In the early planted fields, many pods had aborted seeds and many of seeds that did develop were smaller than normal. When drought occurs during the seed filling stage, the number of seeds and total size of the seed can be reduced as the plant tries to cope and survive with little water,” said Menjoulet.

Podworm continues to be a problem and damaged pods were observed in all fields scouted. “If insecticide control is necessary, double check the pre-harvest interval on the chemical label prior to application so there is not a delay in harvest,” said Menjolet.

Pre-harvest intervals generally range from 14 to 45 days depending on the chemical.

MU Extension agronomy specialists in southwest Missouri are still receiving questions from producers interested in baling or chopping soybeans for livestock feed.

Estimated tonnage for hay or chop ranges from two to four tons per acre with removal rates of about 10 lb phosphate and 25 lb potash per ton. Nitrogen removal will be higher at 45 lb per ton and some adjustments to N application into a corn rotation may be needed next year.

“Several insecticides and fungicides prohibit the plants from being fed to livestock at all. So if you have used chemicals such as Lorsban Advanced, Hero, or products containing captan, these fields can only be harvested for grain,” said Menjolet.

For more information on this scouting report or to learn how you can receive it by telephone each week, contact the MU Extension Center in Barton County at (417) 682-3579. These weekly field crop scouting reports are sponsored by MU Extension in Barton County and the Barton County Soil and Water Conservation District.

PHOTOS AVAILABLE: Photos of the various diseases discussed in this release are available for viewing or downloading in the “crop report” set at www.flickr.com/MUExtension417.

Click here for PDF file Audio Report --- http://tinyurl.com/3mcg6dv

Field Scouting Report for September 21…

Corn Baled, Rain Helps Soybeans and Pests are Few

Tim Schnakenberg, an agronomy specialist with University of Missouri Extension, scouted fields west of Lamar and near Nashville on Sept. 21.

Corn fields appeared to be at least 80 percent harvested. Many fields had the stalks baled up to feed to cattle. “Buyers and sellers of this hay should be aware of nitrate levels that could be high. It is recommended that stalks be tested for this issue,” said Schnakenberg.

Soybeans scouted this week were in R5 and R6 beginning and full seed stages of development, though a few full season fields were at full maturity.

“A much needed rain over the weekend has made the outlook better for the soybean crop, though many doublecrop fields will still be pushed to make a decent yield if we have an early frost,” said Schnakenberg.

The most obvious pests on soybeans currently are green cloverworms, grasshoppers, podworms and a few stinkbugs. Most of the pod damage appeared to be old. Leaf feeding was mostly at 10-20 percent and is mostly due to several small cloverworms in the crop.

“Some of the soybeans are being baled for hay. Soybean hay typically is about 14 percent protein and could have a TDN level in the upper 50s. Issues related to baling soybeans include getting the stalks dry without leaf loss and the quality of the hay is sometimes compromised by the high stalk content,” said Schnakenberg.

PHOTOS AVAILABLE: Photos of the various diseases discussed in this release are available for viewing or downloading in the “crop report” set at www.flickr.com/MUExtension417.

Click here for PDF file Audio Report --- http://tinyurl.com/3kho9b7

Grasshopper Mature corn

Soybean pods Soybean yellowing

Mature soybeans

Field Scouting Report for September 14…

Grasshoppers and Wildlife Moving in to Area Crop Fields

Andy McCorkill, a livestock specialist with University of Missouri Extension, scouted both corn and soybean fields west of Lamar and near Liberal on Sept. 14. Most corn fields were mature with harvest well underway according to McCorkill.

“Problems related to drought stress were prevalent. Local elevators are reporting greatly reduced yields and light test weights. A few loads have tested high for aflatoxin levels as well,” said McCorkill.

Early planted soybeans were mostly in the R5 to R6 stage with beginning to full seed development. Double crop beans were in the R4 and R5 stages with full pod and beginning seed development. “Dry weather conditions continue to be of concern as pods are trying to fill. Some insect feeding on foliage was visible,” said McCorkill.

Grasshoppers were the most apparent feeders. McCorkill said defoliation levels from insect damage ran around five percent. “Insecticide treatment should be considered when defoliation levels from insect damage reach 20 percent defoliation after pod formation,” said McCorkill.

Current market prices and yield potential of the field should be considered before applying insecticide.

“One field in particular showed signs of heavier than normal wildlife feeding. The field’s proximity to nearby wildlife habitat and declining food supply caused by the dry weather conditions we have experienced recently likely played a role in the heavier than normal feeding that was observed,” said McCorkill.

PHOTOS AVAILABLE: Photos of the various diseases discussed in this release are available for viewing or downloading in the “crop report” set at www.flickr.com/MUExtension417.

Click here for PDF file Audio Report --- http://tinyurl.com/3v9kr98

Field Scouting Report for September 7…

Soybean Podworms and Corn Earworms Still Active

Brie Menjoulet, the agronomy specialist with University of Missouri Extension who scouted the fields, scouted both corn and soybean fields in Barton County on Sept. 7. Soybeans in the scouted fields were in the beginning to full seed development stages (R5 to R6).

“I saw pod damage and defoliation consistent with soybean podworm and green cloverworm, reported last week,” said Menjoulet. Soybean podworm is also known as corn earworm, They overwinter as pupae in Missouri soil and also migrate in as moths during the spring.

According to Menjoulet, there are usually three generations of podworm per season, which can create a wide range of sizes and colors of the larvae in the field. Larvae typically change colors as they develop through growth stages.

Regardless of color, look for several dark stripes running horizontally down the length of the larva’s body and for black bumps with protruding hairs. There will also be four pairs of abdominal legs toward the midsection of the worm and one pair of legs at the backend.

Podworms prefer to feed on green pod walls and the seed. They will continue to feed as long as they have a green food source so some of the pods that are alive but missing a seed but are still at risk for further feeding damage.

“When scouting, the best method is to put a white trash bag or sheet between the rows and shake the soybean plants. Counts should be based on foot of row. Yield potential with the current drought damage among other things should be considered prior to spraying,” said Menjoulet.

PHOTOS AVAILABLE: Photos of the various diseases discussed in this release are available for viewing or downloading in the “crop report” set at www.flickr.com/MUExtension417.

Click here for PDF file Audio Report --- http://tinyurl.com/3jjns78

Podworms

Podworm damage