Category Archives: Corn
Two (Uncommon) Foliar Diseases Seen on Fall Corn
In October, I visited a field of corn in Jackson County. Plants had dark brown, circular spots on stalks and the midribs of leaves (Figure 1). Associated with the dark spots on the midrib were smaller spots on the leaf blade that looked like southern rust. There also was a repeating pattern associated with these spots. The disease was Physoderma brown spot, caused by the fungus Physoderma maydis. I confirmed it by examining spores from spots under the microscope. Previously, the only time I’ve seen this disease was… Read More →
Herbicide Management in Corn and Forage Sorghum Silage Crops
Jourdan Bell, Kevin Heflin, Vanessa Corriher-Olsen, and Pete Dotray In response to increasing silage demands, Texas producers are growing more corn and forage sorghum for silage. In recent years, some producers are also making late season decisions to harvest corn intended for grain as silage due to favorable silage markets. As producers make preplant agronomic decisions, it is important to select herbicides that are labeled for the silage crops if there is a contingency plan to chop a grain crop for silage. Although it is commonly… Read More →
Impact of Ponded Water/Flooding on Corn and Sorghum
Ronnie Schnell, Ph.D. Associate Professor and Cropping Systems Specialist Texas A&M AgriLife Extension, College Station Tony Provin, Ph.D. Professor and Extension Specialist – Soil Chemistry Texas A&M AgriLife Extension, College Station Numerous rain events have resulted in flooding or significant ponding of water in many corn and sorghum fields across Texas. While low-lying areas may be flooded, other areas of fields may be saturated for extended periods of time. How long can corn or sorghum survive under saturated or flooded conditions? What impact will these conditions… Read More →
Freeze Injury, Low Temperature Stress and Chill Injury in Corn and Sorghum
Dr. Ronnie Schnell Cropping Systems Specialist – College Station Introduction Recent cold weather has affected newly planted, emerging or emerged corn or sorghum throughout south and central Texas. Corn and sorghum will experience similar types of injury although tolerance to low temperatures does differ between the crops to some degree. Sorghum generally requires warmer soil temperatures. Three types of injury may be observed, depending on stage of growth and temperatures experience above and below ground. This includes imbibition injury, cold stress, and frost/freeze damage…. Read More →
Corn Diseases in South and Central Texas, So Far
This season has been unusual for corn diseases. Early in the year, starting in south Texas and progressing north, the fungal disease, northern corn leaf blight (Figure 1), has been very prevalent. Usually, a few lesions of the disease are seen on the lowest leaves and the disease never progresses. Disease development is driven by frequent rain and temperatures lower than 80°F. In a typical Texas growing season, infrequent rain, but moreover increasing temperatures will hinder the fungus. Weather conditions early in the season supported disease development. There… Read More →
Soil management considerations for upcoming pre-emergence herbicide applications in corn and sorghum
Many farmers across Texas will be thinking about planting corn in just a couple of months, and sorghum shortly after that. Managing soil for good seed-soil contact and for fertilizer nutrients are common concerns as the time for planting nears, but understanding how the management of soil works into integrated pest management (IPM) programs can be helpful to ensuring the effectiveness of expensive pre-emergence (PRE) herbicide applications as well. There are two concepts presented in this article to consider for how soils effect PRE herbicides. 1. Activity –… Read More →
Insect Pest Update
Dr. David Kerns, Texas A&M AgriLife Extension Service Cotton: Cotton fleahoppers (CFH) have been extremely bad in cotton this year throughout the eastern half of Texas. In the Brazos River Bottom we have fields running 100-150% CFH infestation based on terminal inspections; the threshold is 10-15%. These large populations are the result of ample rainfall and production of weedy host harboring CFH. The good news is CFH are easy to kill with the right insecticides. The bad news is the CFH are continually reinvesting sprayed cotton and… Read More →