Witchweed (Striga asiatica) was first collected and identified in the United States during the late summer of 1956. This parasite attacks the roots of plants primarily in the family Gramineae. In the United States it appears to be a potential threat to the corn and grain sorghum crops. The seed of this annual germinates under very exacting conditions and can attach itself to a growing root tip of a host plant. Infestations build up, and spread is by seed which are produced in abundance. Beginning infestations may cause a few stunted crop plants while older infestations may cover several acres or entire fields and completely kill the host plants before they can produce a crop.