Digging Best Option for Controlling Thistles Now
Musk thistles as well as many of its relatives are coming into full bloom. Those pretty purple Musk thistle blooms look nice now but mean problems later. Once the plant has bolted or shot up a seed stalk, control options are limited.
Digging is one of the few options now to prevent their seed from spreading. Plants should be dug or cut off 1 to 2 inches below the soil surface where the root diameter narrows from the crown. Dug plants should be burned or disposed of in a way to prevent seeds from escaping.
Musk thistles are classified as a noxious weed and by law are required to be controlled. If a landowner fails to control noxious weeds on their property, Washington County can serve them with a notice to comply. This notice will give specific instructions and methods on when and how certain noxious weeds are to be controlled.
The best growth stage for controlling musk thistle is the rosette stage. Rosettes can be found in both the fall and spring. Fall chemical applications are preferred because when combined with the effects of winter, a higher percentage of the plants will be killed. University of Nebraska-Lincoln research has shown that late September or October is the best time to treat the plants.
Controlling musk thistle must be done on a community basis to be truly effective. It takes neighbors working together to truly keep musk thistles under control.
Standing Water Impacts Corn and Soybeans
The abundant rains we have received have resulted in flooding and ponding of water in many fields near creeks and rivers. Standing water poses a threat to our spring planted corn and soybeans.
Corn seedlings with less than six leaves, can withstand four days under water if air temperatures are less than the high 70s. If air temperatures are greater than that, seedlings may only survive for one day.
Soybeans are also at risk in standing water. The extent of the flooding on soybean plants is related to temperature of the water, the amount of water motion and the duration of the flooding.
Research from Minnesota shows that flooding for 6 days or more may result in a significant yield loss or loss of the entire crop. With air temperatures in the 80’s, soybeans may only survive a few days.
We need rain to produce food but at times it can be too much of a good thing.
