Indian Hemp ( Apocynum cannabinum ) is a species of plant . It is also known as Dogbane , Amy Root , Hemp Dogbane , Rheumatism Root , and Wild Cotton . Apocynum cannabinum ( Dogbane , Amy Root , Hemp Dogbane , Indian Hemp , Rheumatism Root , or Wild Cotton ) is a perennial herbaceous plant that grows throughout much of North America - in the southern half of Canada and throughout the United States .