Apocynum cannabinum /Dogbane Family
This plant has been confused with common milkweed by people wanting to feed hungry monarch caterpillars. It does "bleed" white sap when cut, but the leaf placement is different than milkweed. Also, Indian Hemp stems are tough and stringy, and they branch, none of these traits are found in the unbranching, hollow-stemmed common milkweed. By the way, monarch caterpillars will not eat these leaves. Indian hemp and other plants in the Apocynum genus are poisonous to horses, cattle, sheep, goats cats, dogs, and humans. The plants contain apocynamarin, cynarin, and apocynein. The last 2 poisons are cardiac glycosides which cause irregular heartbeats and can result in death.
Where seen:Oak Ridge Greenways, Haw Ridge, University of Tennessee Arboretum, widespread