August 2023 E-Newsletter

by Bobbi Sabine

Spreading dogbane (Apocynum androsaemifolium) has been found throughout the great state of Michigan, from Monroe County all the way to Isle Royale. It thrives in sand or rocky open forests and savannas, as well as clearings, old fields, roadsides, and prairies. Its waxy five-petaled pale pinkish flowers are generally in pairs or clumps of about 8-12 at the end of the stem, giving way to the characteristic paired seed pods which resemble skinny green beans. The seeds inside are silky-haired like milkweed.

Its close relative, Indian hemp or hemp dogbane (Apocynum cannabinum) is slightly less common north of about Gaylord. It grows in similar habitat but leans more toward wet soils – shores, thickets, riverbanks, marshes and meadows, but also will tolerate disturbed ground in upland areas. Flowers are more creamy white and densely clustered on the end of the stems.

A host to hummingbird moths, dogbane is said to be poisonous and may cause cardiac arrest if ingested. The stems contain a white sap capable of causing skin blisters. Other symptoms include dizziness, color  hallucinations, cold sweats, and excessive urination.

The word Apocynum means “poison to dogs.” Though inedible, the stalks provided a good source of fiber for Native Americans who used it to make thread, bows, nets, straps, fishing lines, bags, and clothing.

Not entirely without medicinal use, a weak tea made from the dried roots was used by tribes to induce vomiting, treat cardiac diseases, and as a vermifuge (to expel parasitic worms).

It can also be used in phytoremediation by taking up lead from the soil through its roots and sequestering it.

Photo Credit: R. Schipper, U of M