Arrow bamboo
Botanical Name
Pseudosasa japonica
Family
Poaceae (grass)
Also known as
Bamboo
Where is it originally from?
Japan, South Korea
What does it look like?
Medium-sized, clump-forming perennial bamboo (<5 m tall) with extensive underground root systems, and round, dark green stems with a white band just below each ring (node) where branches attach to stems. Each branch has 1-7 flat, green leaves (35-40 mm wide x 250-300 mm long), and hairless leaf sheaths, often purplish above, that are longer than the distance between stem nodes. Flattened grass-like flower spikes (4-9 cm long) are purplish on the exposed side, and can flower continuously for several years.
Are there any similar species?
There are several other bamboo species in New Zealand.
Why is it weedy?
Forms very dense stands that exclude all other plants and that spread outwards by rapid growth of the thick rhizomes.
How does it spread?
Spread is vegetative by growth of rhizome, viable seed is uncommon.
What damage does it do?
Rapidly crowds out other plants as it forms dense stands.
Which habitats is it likely to invade?
Scrub, forest margins, riverbanks, roadsides, in or around plantations, urban areas, waste places.
What can I do to get rid of it?
1. Cut down near the ground: Mulch leaves and stems. Dig out rhizomes and root mass, and dispose of them at a refuse transfer station.
2. Cut down near the ground: Mulch stems and leaves. Allow to resprout, and spray the new growth with amitrole (333ml/L + penetrant) or 520g/L haloxyfop-P-methyl (150ml/10L + penetrant) before the regrowth reaches 60 cm tall. Again, allow to resprout and spray the regowth. Usually 4-5 applications are required before it stops resprouting.
CAUTION: When using any herbicide or pesticide, PLEASE READ THE LABEL THOROUGHLY to ensure that all instructions and directions for the purchase, use and storage of the product, are followed and adhered to.
What can I do to stop it coming back?
Monitor the site for regrowth from roots and rhizomes. Repeat treatments will usually be required. Plant the site with local, native plants to produce shade, but wait six months from last herbicide application.
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