In the backyard or in the wild, roguing (selectively pulling or cutting weed plants) and herbicide spot treatments can help prevent small patches of invasive weeds from becoming large infestations. However, herbicide applications may be of little value where senescent plants have already set seeds, because the dead “skeleton” plants may bear dormant but living seeds, which can initiate new infestations.

In the past, such plants may have been removed by stacking and burning them. However, under present conditions, burn permits are hard to come by. Landfill disposal is another option, but transporting seed-bearing plants may spread the seeds, making the problem worse instead of better. Deep burial of plant material...