Post Rock Extension hosts KSU Sorghum School

by Sandra Wick, Agriculture and Natural Resources Agent

Dr. Curtis Thompson, K-State Research and Extension Weed specialist and State Leader, visits with ag producers and agribusinesses on weed control strategies in grain sorghum.

Recently, Post Rock Extension District hosted one of the KSU Sorghum Schools in Beloit. Nine K-State Research and Extension faculty presented information on weed control strategies, disease management, planting management, risk management, web and mobile apps, soil fertility and insect management.

The following is some of the highlights from the meeting:

• Be on the lookout for weeds early in the season. For season long coverage, a pre-plant and post-emergence herbicide application is recommended.
• KSU research has determined palmer amaranth (pigweed) has developed some weed resistance in Kansas. Pre-plant herbicides that have shown some control include Callisto, Callisto plus Atrazine, Balance Flexx plus atrazine, and Lumax EZ.
• DuPont herbicide “Zest” – new herbicide for ALS resistant sorghum for 2014. Similar to Beacon or Accent.
• Marestail control in grain sorghum has become a challenge. Several combinations of herbicides have shown some control including Atrazine/Dicamba; Split application of Lumax (pre-plant and at planting); or Huskie with Atrazine.
• Greatest return in nutrient management for grain sorghum is nitrogen and phosphorus, but only if based on SOIL TESTS.
• Several management strategies can affect nitrogen update including tillage/residue cover; soil type, texture and drainage; application methods and the rate.
• Remember the 4 R’s of fertility management including the RIGHT rate, place, time and source products.
• Dribble and knifing are two of the more efficient methods of application for nitrogen.
• The rate of “tie-up” of nitrogen (N) depends on the kind of residue.
• Timing of the nitrogen application “at planting” yielded a higher grain sorghum yield in KSU research with Agrotain.
• Moisture is needed to move the sidedress N fertilizer application down into the soil profile.
• The use of urease inhibitors should be based on your tillage methods. The use of urease inhibitors in a “conventional” tillage is not needed because of the incorporation of the nitrogen while a “no-till” system will see a response from urease inhibitors.
• Grain sorghum may see a response to the micro-nutrient, Chloride (CL) with an application, if the soil tests indicate less than 30 lbs. in the soil profile based on a 24” sample.
  

If you were unable to attend and would like information from the meeting contact any office of the Post Rock Extension District in Beloit, Lincoln, Mankato, Osborne or Smith Center.