Definitionen
1.NounSeveral North American plants with black roots of:
genus Pterocaulon, such as Pterocaulon pycnostachyum (dense-spike blackroot) and Pterocaulon virgatum (wand blackroot)
species Veronicastrum virginicum (Culver's root)
species Aletris farinosa (colicroot)
2.Noungenus Pterocaulon, such as Pterocaulon pycnostachyum (dense-spike blackroot) and Pterocaulon virgatum (wand blackroot)
3.Nounspecies Veronicastrum virginicum (Culver's root)
4.Nounspecies Aletris farinosa (colicroot)
5.NounSeveral plant diseases caused by fungi in the genus Aphanomyces causing that cause roots to rot and turn black.