Agronomy eUpdate March 16th, 2023

Issue 947

Residual herbicides for corn

Residual herbicides that kill weed seeds/seedlings as they germinate or emerge are an important component of herbicide applications at or before the time of corn planting. Many cases of herbicide-resistant weeds have resulted from over-reliance on post-emergence herbicide applications, thus it is essential to include one or more residual herbicides available for corn.

corn weed control pre-emergence residual herbicides 

Spring planting is approaching: Soil temperature and moisture status

Planting date is one of the most critical factors to decide for row crops. Rather than just calendar dates, farmers should consider basing this decision based on soil temperature and moisture. Every summer row crop has an optimal soil temperature for its emergence. A late freeze can also affect any early planted fields.

planting soil moisture soil temperature planting date 

Soil temperatures across Kansas: Current and historical averages

We are now two weeks into meteorological spring. Warmer air temperatures are fast approaching, and those will lead to warming soil temperatures. One important benchmark for spring planting is the arrival of soil temperatures that reach and consistently stay above 50°F. Is Kasnas ahead or behind normal so far this spring?

climate soil temperature 

Considerations for early fungicide applications on wheat in 2023

As wheat starts to green-up across the state, questions are coming in about the benefit of early fungicide applications. Research at K-State and in other regions continues to demonstrate that it is often possible to achieve high levels of foliar disease control with a single fungicide applied between flag leaf emergence and heading growth stages.

wheat disease fungicide 

First hollow stem update - March 13, 2023

This is the latest report on the status of first hollow stem development as tested by the K-State Extension Wheat and Forages team. Producers should use this information as a guide and monitor FHS from an ungrazed portion of each individual wheat pasture to make the decision of removing cattle from wheat pastures.

wheat dual purpose first hollow stem 

Potential pest of soybeans and alfalfa in Kansas: Mealybugs

First identified in 2008 as a potential pest of soybeans in the US, trochanter mealybugs have a wide variety of hosts including corn, sorghum, and alfalfa. While their role as a pest of soybeans is still not fully understood, it appears that mealybugs have the potential to be a problem in Kansas alfalfa as sporadic infestations have been detected in the western part of the state as recently as 2022.

soybeans insects alfalfa mealybugs 

2022 Kansas cool-season forage performance tests

The results of the 2022 Kansas Performance Tests for cool-season annual forage varieties are available online. Results are available for both yield and nutrient value for the cool-season forages. Annual forage performance tests are conducted each year by the Kansas Agricultural Experiment Station.

forage variety trials cool-season