Redroot (amaranthus) (Amaranthus powellii)
Most abundant in the North Island. Annual.
Identification
A tall upright plant with green leaves that often have a red tinge. The first true leaf of the seedlings has a notch at the tip. It has greenish-brown flowers that feel prickly and produce shiny black seeds.
Characteristics
A summer annual that dies with frosts in late autumn. It can be a problem in spring-sown pastures because it forms dense patches of upright plants.