Mexican Feather Grass

Also known as:
Fine-Stemmed Needle Grass
South America

General description

Perennial, drought resistant tussock grass with fine wiry leaves <70cm high. Flowerhead (Oct-Dec) feathery panicle, erect when young & weeping over when mature. Huge numbers of rough-coated seed (<120,000) with tufted hair at base.

Poor or dry pasture, open areas, coastal areas.

Seed spread short distances by wind & by attachment to wool, fur, clothing, machinery etc.

Crowds out pasture species, reducing productivity. Replaces native species in open & coastal areas. Stock forced to eat it get indigestible balls in their stomachs, leading to weight loss & starvation.

Site management

Do not burn or graze, exclude all livestock. Plant dense low cover where appropriate after control. Follow up on open sites for at least 10 years. Plant seeds prolifically into bare ground, do not spray single plants with glyphosate to create bare patches.

Recommended approaches

1. Report it immediately to the Auckland Council Biosecurity team, who will arrange for its control at their expense.
2. Grub out scattered plants.
3. Weed wipe dense infestations, all year round (100ml glyphosate + 2ml penetrant/1L).
4. Knapsack spray dense spots (spring – summer) amongst desirable broadleaf species (60ml haloxyfop + 50ml crop oil/10L).
5. Spray dense infestations, all year round (150ml glyphosate + 20ml penetrant/10L).

Caution: when using any herbicide or pesticide PLEASE READ THE LABEL THOROUGHLY to ensure that all instructions and safety requirements are followed.

Similar species

nassella tussock
Nassella trichotoma

Nasella tussock has brighter green leaves and larger projection on base of floret (3-4mm). The awn (the long bristle-like appendage extending from the end of the seed) is 4.5 to 9 cm long in N. tenuissima; 2 to 3.5 cm in N. trichotoma.

Chilean needle grass
Nassella neesiana

Chilean needle grass has much broader leaves. The awn (the long bristle-like appendage extending from the end of the seed) is 4.5 to 9 cm long in N. tenuissima and 6 to 9 cm long in N. neesiana.

RPMS status

Total Control - Whole Region
National Pest Plant Accord species - nationwide
Mexican feather grass - Main species image