Thursday, May 18, 2017

"Yellow Brick Field"

posted by Jochum Wiersma, UMN Small Grains Specialist

The Wizard of Oz's Yellow Brick Road may have been fictional element.  Some springs, solid yellow small grain fields are not.  

Although few reports of early seasoning yellowing have come in to date, Memorial Day Weekend is just around the corner and historically that's often the time one of the causes of early season yellowing is observed.  

Follow this link to an article I posted in 2016 that discusses the most common causes of early season yellowing. 

Barcodes in Wheat, Barley, and Oats?

prepared by Jochum Wiersma, UMN Small Grains Specialist

The beautiful, dry sunny weather with high winds this past week and weekend has allowed many of you to make great strides with planting. Unfortunately this also exposed young small grain seedlings to same conditions. 

Seedlings with the yellow, constricted 
appearance symptomatic for heat 
canker  (photo courtesy of  Byron Fisher)
The daytime heat at the soil surface can and has caused heat canker. The tender young tissue at the soil surface basically has been 'cooked' and this appears as a yellow band that is slightly constricted (Photo 1). As the leaf continues to grow, this yellow band (1/8 - 1/4") moves upward and away from the soil surface. 

If the hot and dry weather last for several days, its is possible to see repeated bands, much like a barcode. The damage is nicely depicted on page 81 of the second edition of the Small Grains Field Guide. Because of the high winds, the tips of leaves may fall over or even break off at the yellow band and give a field a very ragged appearance.

Damage from heat canker is temporary and should not affect further growth and development.

Tall trees catch much wind..or how to avoid the risk of lodging in small grains.

posted by Jochum Wiersma, UMN Small Grains Specialist

The meaning of Dutch proverb "Tall trees catch much wind" doesn't have anything to do with lodging and more to do with the propensity of people to be jealous of those that stand out, but in this context is a nice way to describe the physics off lodging. Simply put, it takes less wind power for a tall crop to lodge, simply because the amount of force needed to bend the stem is less.

Last spring I wrote a summary about the use of growth regulators to reduce the risk of lodging. 

 It can be found here:

Monday, May 15, 2017

Preemergence Herbicides are a Proactive Approach for Weed Management

prepared by Tom PetersExtension Sugarbeet Agronomist, NDSU & U of MN 
and Rich ZollingerExtension Weed Specialist, NDSU

Agriculturalists frequently advocate for use of preemergent herbicides. You heard state Extension Specialists recommend this in presentations during winter meetings and you have read it in trade magazines while you relax at home. Now it is time to put what you have heard and read into action. However, you are not so sure anymore, for some reason. The following evidence is intended to encourage you to apply herbicides preemergence.

Looking for Soybean Growers to participate in a research study on Soybean Aphid Population Levels and Buckthorn Density

We are looking for soybean growers who have 10 or more acres of woodlands or forests that they own and/or are publicly owned and adjacent to their soybean field. 

Soybean aphid has quickly become one of the most damaging pests of soybean in the Great Lakes Region, negatively impacting soybean yields and quality.  There are numerous options for managing soybean aphid ranging from aphid resistant soybean varieties, insecticides, and predatory insects. These treatments focus solely on the field. 

Soybean aphid on buckthorn in the fallHowever, soybean aphid requires buckthorn to overwinter. Buckthorn is a widely distributed, invasive shrub common in forests, woodlands, and hedgerows. There has been little research exploring the relationship between buckthorn density and soybean aphid populations.

The MN Soybean Research and Promotion Council has recently funded a project to explore this topic. The long-term goal of this proposal is to explore treatments methods for controlling buckthorn, decreasing soybean aphid populations, thus increasing quality and yields for soybean growers. 

This in an interdisciplinary project that brings together faculty, Extension educators, and soybean growers to try to answer to the question, “can buckthorn management have economic and ecological benefits for soybean growers?” 

Field crews will sample in both the woodland and the soybean fields. Field crews will set-up forest inventory plots in the woodlands to gain information on the overstory, regenerating seedlings and saplings, and buckthorn density once during the summer growing season. This information will be shared with the landowner. Field crews will use transects to sample soybean aphid populations 2 to 3 times during the growing season to quantify how soybean aphid levels change. This information will be used to test the relationships between buckthorn density, buckthorn proximity, and soybean aphid populations through the growing season.

If you are interested and/or would like additional information regarding participating in the study feel free to call:

      Dr. Marcella Windmuller-Campione 
      612-624-3699 (office) or 
      847-772-5458 (cell) 

We are planning to begin early season sampling in June.