Napier grass

Napier grass is a robust perennial grass forming large bamboo-like clumps growing up to 7 metres high.

Description

• Large leaf blades (20-120 cm long and 1-5 cm wide) have a prominent whitish central vein.

• Flower spikelets are surrounded by numerous bristles, one of which is larger than the others (i.e. 2-4 cm long)

• Seed-head is spike-like (8-30 cm long and 1.5-3 cm wide) and very bristly.

• Seeds are predominantly spread by wind, moving water and seeds attached to fur, clothing and vehicles. But can also spread vegetatively via tillers and stem fragments.

• Habitats include grasslands, forest margins, swamps, wet grasslands, roadsides, rivers and waterways.

What you need to know

Napier grass is an aggressive grass that grows rapidly, colonising new areas and forming dense thickets that invade native vegetation.

Management approach

Napier grass is declared an unwanted organism by the Ministry for Primary Industries (MPI) because it is capable of causing harm to the natural environment, physical resources or human health in Aotearoa/New Zealand.

These species pose a high risk to our environment, economy, recreation, and cultural values.

Rules

Any species declared a pest, including unwanted organisms, cannot be sold or be in a place where plants are being sold. Pest plants cannot be propagated, bred, or multiplied, communicated, released, or cause to be released, or otherwise spread.

Control

Do not attempt to undertake control of Napier grass yourself. Report any sightings to us.