As of September 2, 2019, Palmer amaranth seed has been added to South Dakota’s list of prohibited noxious seeds. Seeds for sale within South Dakota may not contain prohibited noxious seeds in any amount.
In addition to Palmer amaranth, other noxious weed seeds include Canada thistle, find bindweed, hoary cress, horse nettle, leafy spurge, perennial sowthistle, and Russian napseed. Prohibited noxious seeds are highly destructive and difficult to control. Noxious weed seeds cannot exceed a total of 20 per pound. Restricted noxious weed seeds are highly objectionable and difficult to control in specific crops, fields, lawns, and gardens.
The South Dakota Department of Agriculture encourages those buying seeds to carefully examine the labels of their seed purchases and ask to see the official seed analysis report if a percentage of weed seed is listed. Doing so will help deter the spread of weeds in South Dakota.
According to South Dakota State University extension, Palmer amaranth can be found in South Dakota, but it is currently not wide spread. SDSU Extension staff say it may be possible to limit the scope and economic burden this weed could cause if South Dakota producers and agronomists are vigilant throughout harvest.