What does it look like?
Noogoora bur is a fast-growing summer annual that can reach heights of 2m - 2.5m. It’s named for the clusters of distinctive, egg-shaped burs that contain seeds. The burs are 10-25mm long and covered in hooked spines with two thick spines at the tip. The plant can grow with a single stem or as a multi-stemmed bush. The leaves are dark green above, paler below, and irregularly lobed with purplish veins. The stems are rough to the touch and streaked with purple.
Noogoora bur favours fertile soils and is often found close to water. It usually grows on arable land and in paddocks, but it’s also found on disturbed ground, stream banks, and other riparian areas.
Why is it a problem?
Noogoora bur contains chemicals that can impede the growth and germination of neighbouring plants. It produces large quantities of seeds that germinate into a fast growing and highly competitive weed that can cause significant losses in many crops. A single plant can produce 10,000 seeds, which are contained inside burs. The seeds spread via animals, clothing, and agricultural machinery. They may also be spread in seed, feed, gravel and soil and also float, so can be spread by water. Seeds may remain dormant in the soil for many years.
Control methods
Noogoora Bur is listed as an Exclusion Pest under the Hawke’s Bay Regional Pest Management Plan 2018-2038.
If you think you have seen Noogoora Bur, please contact us on 06 835 9200. Do not attempt to control it yourself.
Related links
https://www.cabi.org/isc/datasheet/56864
https://www.nzpcn.org.nz/flora/species/xanthium-strumarium/
http://www.nzflora.info/factsheet/Taxon/Xanthium-strumarium.html
Notify Council
If you think you've found this pest, please get in touch with our Biosecurity Team at biosecurity@hbrc.govt.nz or call us on 0800 108 838.
Management Programme
Exclusion Programme
Exclusion pest plants are organisms known in other parts of the country but are not thought to exist in Hawkes Bay. An Exclusion Programme aims to prevent a specific pest from establishing in the region before it arrives. With economic returns of around 1:100, prevention is always the most cost-effective strategy available. The faster we can detect an incursion, the more economical and successful our response efforts are likely to be. If an organisms listed under an exclusion programme was to establish, it has the potential to cause adverse effects on production, economic wellbeing, and environmental values.
More informationRules
Sections 52 and 53 of the Biosecurity Act (1993)
No person shall knowingly communicate, cause to be communicated, release, or cause to be released, or otherwise spread any pest or unwanted organism, in accordance with Sections 52 and 53 of the Biosecurity Act 1993
More information
