How to identify pigweeds
Pigweeds (Amaranthus spp.) are difficult to identify from each other. But identification is crucial for developing a successful weed management program, particularly in an agricultural landscape that is heavily reliant on herbicides (and where resistance is common). Species can also differ in their growth rates, which can impact the success of physical management, like cultivation. When thinking about pigweed identification, focus on a few key characteristics:
- The shape of the leaf blade and the length of the petiole, as well as the hairiness of the stem.
- The presence of male and female flowers on the same (monoecious) or separate (dioecious) plants and the structure of the flower heads (inflorescence).
- The size of the plant.