Mouse-eared Chickweed

Cleavers (Galium aparine) are a common, widespread annual weed found throughout New Zealand. A significant weed of cereal and horticultural crops and often found scrambling up fencelines and hedgerows Cleavers have a scrambling, clambering growth habit and “stickiness” due to tiny hooks on its stems and seeds.

Chickweed (Stellaria media) is a widespread, very resistant weed, it is found in the North and South Island in areas of cultivated land and roadsides. Commonly seen in winter, it does not favour drier conditions. It is a problem in small grain crops such as barley, causing up to 80% yield losses. It a low growing spreading annual (up to 40 cm) with, light green soft leaves, (lighter underneath) up to 2 cm long. The leaves are in opposite pairs on hairy stalks. Flowers are white, about 1 cm in diameter, with 5 deeply divided petals that appear to be 10 petals. Chickweed flowers and sets seeds simultaneously. The seeds are contained in green egg-shaped capsules, and one plant produces about 15,000 seeds, which remain capable of germination in the soil for up to 5 years.

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.

Hedge mustard (Sisymbrium officinale) is a widespread common annual herb, found throughout New Zealand in pasture, cultivated land, gardens and road-sides. It grows in a rosette formation up to 1 m tall and has broad hairy leaves with deep lobes. The end lobe has a rounded shape. Flowers are very small, pale yellow, numerous, and can be found at the top of the main stem or at the end of branches. Stems are upright, with downward pointing hairs and alternate branches. Seed pods are found close to the stems; seeds are 1 mm long, brown and oblong.