Should I spray Canada thistle this Fall?
According to Tim Seipel, MSU Cropland Weed Extension Specialist, producers need to wait until it warms up before they spray. Hopefully, producers will get another window of good fall weather to get out and clean up fields. Glyphosate will not be absorbed if temperatures are below 40 degrees.
In addition, spraying depends on what is going to be sprayed. Canada thistle stalks from this year were recently hammered by the cold. Stalks have most likely finished moving sugars around especially if the temperature gets down to 15 degrees. However, Canada thistl...