Extension Crop and Pest Reports (Aug. 17-21)
Corn is now primarily in the dent stage (Photo 1). A lot of corn has experienced heavy disease pressure this year (Photo 2). Hill ground generally looks good due to plentiful rains. Bottom ground is variable as some areas were too wet and nitrogen loss occurred.
Soybeans are in various stages of seed fill (Photo 3). Sudden death syndrome is now apparent in pockets within some fields.
The summer is moving along quickly and crops are maturing. A lot of dry edible bean fields have mature bean pods and are changing color. We will be harvesting dry beans within two weeks. Some of our dry bean fields where growers struggled with their herbicide applications have severe weed pressure. See the Photo 1 and 2 of four-foot tall Kochia and also Palmer Amaranth infesting the beans.
Corn is mostly at the milk stage just moving toward dough. A lot of corn is being sprayed for Spider Mites. The sugar beets continue to look good as growers keep the irrigation going during this hot and dry summer. There has been some treatment of Cercospora leaf spot although warmer dryer conditions do not favor this disease. Early sugar beet harvest will begin the last day of August. Alfalfa growers are mostly finishing their third cutting.
We have some dryland corn that is struggling with the drought conditions and some other dryland crops such as black eyed peas that could use a shot of water. Sunflowers are coming through bloom and are generally deep rooted enough to get through these dry conditions. In most areas range land is getting very dry and brown.
The third cutting of alfalfa is baled and the fourth is slowly growing. Some corn fields are in late milk, but most are in dough to early dent stages. Bacterial leaf streak is very present in fields this year and some flare ups of gray leaf spot and a lot of physoderma brown spot. We did confirm southern rust for Dawson, Buffalo, and Hall Counties (Photo 1). In seed corn fields, most all of them in the area have had the male rows removed so they are progressing nicely. With the exception of late planted fields, most of the soybeans are in beginning to late seed elongation/fill (R5—R6). We are starting to see sudden death syndrome (SDS) show up in soybeans (Photo 2).
We had some issues with spider mites this year in both corn and soybeans, but lots of reports in soybeans this year. Some folks made multiple miticide applications on the same fields.
It’s very dry and irrigation systems have not stopped running. Parts of our region were fortunate to catch rainfall in the past couple weeks, but others are still very dry. We had a light shower this week in the southwestern corner of Buffalo County but not enough to make it into the rain gauge. Crops on pivot corners or dryland fields are starting to show signs of drought and heat stress. Corn is starting to turn brown in spots and leaves are dropping. Soybeans have a gray-green cast, and some are starting to drop leaves.