Directory: Pests: Weeds: Californian Thistle (2)   Articles Californian thistle - Cirsium arvense Information on one of the most common thistle species in New Zealand covering recognition and control. A very troublesome weed in pastures that is difficult to control. Controlling California Thistle Organically Controlling California thistle organically is very simple. Research shows seed plays no role in the spread of this species in pastures. The creeping root system produces many buds and some of these give rise to a new crop of shoots after winter. Current Weather Warnings | Bookmark this page | Suggest a listing | Advertise on this page | Our Philosophy This page was last updated on 01 May 2013 All content and images copyright © 2013 Small Kiwi Farms New Zealand. Copyright of linked pages is retained by their owners. Small Kiwi Farms New Zealand is unable to give any assurance regarding the accuracy of this information.