Willow Weed

Persicaria maculosa

Willow weed (Persicaria maculosa) is an erect and sprawling summer growing annual that can be a serious weed in crops (e.g. maize). It has reddish stems and pink spike like flowers. It is common in the spring and summer throughout New Zealand but is quickly killed by frosts. A similar species, water pepper, grows taller and is common in wet places.

Cotyledons:

Long
Apex rounded
Base not tapered.
Stalkless

Leaves:

Thin spear-shaped
Rigid

Related Pests

Groundsel

Senecio vulgaris

Groundsel (Senecio vulgaris) is an annual weed, found throughout New Zealand. It is a common weed in arable and horticultural crops, gardens and waste areas. The erect weed grows to 50 cm tall with soft, leafy stems and distinctive yellow flowers.

Fathen

Chenopodium album

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.

Spurrey

Spergula arvensis

Spurrey (Spergula arvensis) is a fine-stemmed, sprawling annual weed which is commonly found throughout New Zealand. It can often grow dense. Severely competing with and smother crop seedlings and establishing pastures. Spurrey germinates in the autumn and spring.

Nettle

Urtica urens

Nettle (Urtica urens) is present New Zealand wide except for Northland, Taranaki and Westland. It is well known as stinging nettle due its characteristic of causing swelling and stinging to the skin upon contact. The erect 60 cm tall annual is often found on farms in stock camps where it needs bare ground to germinate. Animals will not graze it. Nettle can also be a troublesome weed in cropping and horticulture.