Research shows the need for patience and persistence when battling perennial weeds such as purple loosestrife over multiple years. The younger the stand the faster the control was achieved.

Cottonwood offers many benefits, but also can be an invasive and difficult-to-control weed. Nebraska researchers studied control efficacy of eight herbicides over two years and found three products provided total control more than a year; however, they also noted a caution for areas with high water tables.

Researchers tested two herbicide strategies in soybean to see how preemergence herbicides would delay the critical time of weed removal, likely reducing the number of herbicide applications needed in a season.