Clovers

Annual poa (Poa annua), also known as annual meadow grass, is a fast growing annual grass found throughout New Zealand in a wide range of crops. While individual plants tend to be small, populations of this grass weed tend to be large and they then compete for light, nutrients and water. Poa annua is best identified by the boat shaped tips to its leaves and the two parallel veins (often referred to as tramlines) that can be seen if the leaf blade is bent backwards. Germination takes place throughout the year and is set very quickly meaning populations soon increase.

Black nightshade (Solanum nigrum) is a significant weed in arable and horticultural crops but it is also common in disturbed pasture. Black nightshade is present throughout New Zealand but less so in the lower South Island. Distinctive black berries (7-10 mm) can be found on mature plants.

Fathen (Chenopodium album), pronounced fat-hen and sometimes called fat hen, is one of the most serious weeds of cropping throughout New Zealand. It is an annual that germinates in the spring and early summer and then dies off in the autumn with frosts. Fathen is an extremely vigorous weed that can quickly outcompete and smother crops. An upright plant that can grow to 2 m tall and is a prolific seeder.