Weed Control Iowa
Notes from an ISU presentation on weed control
Weed control is three steps
1. Base management
a. weed emergence pattern (time) is different for different weeds
b. most seeds are short-lived
c. focus on reducing/eliminating seed bank
2. Effective herbicide management
a. focus on pre-emergence with residual which includes gps 14,15, 3.
b. use full rates
c. scout after planting
d. use layered residual herbicides, be ready to use additional pre-emerge after planting
e. post-herbicide : timing is everything don't lets weeds get too big 2-4 inches
f. Good coverage requires right spray volume and nozzles
3. Integrated managaement practices
a. add diversity
b. don't let a residual gap appear
c. mechanical means, crop rotation and so forth should be considered when possible
The take-home I got out of it is maybe the need to add a second pre-emerge just before crop emergence to add to the length of the residual and then hope the weather didn't mess up the residual coverage before canopy.
These are my scratchy notes so I probably got some of it wrong.