A third of a century of studies and trials of yellow starthistle control (1970-2006) has been conducted by U.C. Davis, public land managers, and volunteers. The principle methods employed are burning, pulling, release of insects, grazing, herbiciding, planting of native grass seeds and mowing. Unfortunate the best that any of these methods, or combination of methods has achieved, is control of yellow starthistle within three or more years of activity.
The usual starthistle control methods, like burning or spraying Transline®, have never been evaluated to discover their impacts on water quality, non-point source water pollution, and the impacts on non-target organisms, especially Threatened, Endangered or Sensitive (TES) plant and animal species.
Before wholesale aerial spraying by helicopter of Transline® is started Statewide, perhaps more environmentally friendly methods could be investigated?
That's why our firm, after 19 years of test-plot work, has developed two successful yellow starthistle control techniques that shorten the time needed to control the plants, utilizing the most environmentally friendly methods: the Temporary Method and the Permanent Method.
The Temporary Method works within 60 days or less, and controls yellow starthistle close to 100% for many years.
Our method's success rests on the ecological concept, that starthistle is one of the many European exotic plants that have spread, to cover 99.9% of California's grasslands. Starthistle is just a "non-useful" portion of all those exotic species---whereas some people might see wild oats, ripgut grass, "Blando" brome, "Zorro" fescue, "Panoche Red" brome as "acceptable exotics", as they are useful for hay and animal fodder. But ecologically, all the exotics work together to destroy and displace California's original native grassland ecosystem.
The Temporary Method, however, is only a way to have quick results to wipe out the exotic problem of starthistle within 60 days or less, but there's a chance that starthistle can return, if a functioning local native ecosystem is not put back in its place.
The Permanent Method is to replace the yellow starthistle with the original local California ecosystem species. Just like a good paint job on your car, it is more expensive in materials and effort to reintroduce a local ecosystem that can function on its own.
Both processes or techniques do not use any herbicides, mowing, burning, pulling, release of insects, or grazing---instead they rely on the local ecosystem's ability to heal itself.
Our methods and processes are available for licensing only to public land managers, on a per acre rate of $25 per acre for the Temporary Method, and $100 per acre for the Permanent Method. The costs of materials, labor to apply the methods, and any additional consulting, is extra.
We are confident that once our methods and processes begin to be employed, that within a relatively short amount of time, starthistle will be only a historic footnote of a former weed problem in California.
A UC Davis experiment in the Sacramento valley, trying to convert Star thistle/exotic annual grasses, back to perennial native grasses, at http://www.ecoseeds.com/road.test.html, for $450,000.
Updated August 25, 2006