Unwanted plant pest Noogoora bur (Xanthium strumarium), is quite literally a space invader.

It's a strong plant that can grow rapidly and has the potential to compete with crops and pasture, poison stock and reduce wool quality.

Noogoora bur (Xanthium strumarium), can poison stock.

Bay of Plenty Regional Council is currently battling to eradicate Noogoora bur from several maize paddocks in the Western Bay.

The weed is an annual herb, with maple like leaves on short, purple-streaked stems. Clusters of 7-25mm long burs grow at the leaf nodes. It can grow up to 2.5 metres in height, growing upright among groups or more sprawling in open ground.

Its burs have spiny hooks that attach themselves to animals, clothing and farm equipment. The burs also float well and are moved by water.

Each plant can produce up to 11,000 seeds, which are commonly spread through contaminated agricultural seed and machinery. They can lie dormant in the ground for many years, germinating when soil is disturbed.

Council is urging farmers and contractors not to help this alien invade local farms. Stop the spread by buying clean maize seed from reputable sources. Check and clean harvest machinery between properties; and insist all machinery and material to come onto your land is weed-free.

If you see the pest, report it by calling a Bay of Plenty Regional Council land management officer on 0800 884 880.