In the interest of learning more about invasive weeds here’s a key that you may find useful in identifying Johnsongrass and Shattercane, two of the noxious weeds on Pennsylvania’s list.
Key for identifying common grassy weed seedlings in Pennsylvania courtesy of Penn State Agronomy.
Getting a few steps into the key, here’s where johnsongrass and shattercane are differentiated:
6A. Thick, white rhizomes just below soil surface…..Johnsongrass, Sorghum halepenese, a perennial
6B. No rhizomes, fibrous root system like corn…..Shattercane, Sorghum bicolor, an annual