In the greenhouse, ground dried sunnhemp residues (applied mixed with the soil at
1.6%w/w) reduced percent germination of lettuce (Lactuca sativa L.) and smooth pigweed
(Amaranthus hybridus L.) to a similar degree as that caused by cereal rye (Secale cereale
L. subsp. cereale) residues (applied at 1.5% w/w).