- Author: Joseph DiTomaso
Medusahead (Taeniatherum caput-medusae) is one of the most problematic invasive grasses on many California rangelands. It is difficult to control selectively in grasslands. Prescribed burning, grazing, and herbicides have been tested with some success but are not practical in all situations. The selective herbicide Milestone (aminopyralid), normally used for control of certain broadleaf species such as thistles, suppresses some annual grasses when applied pre- or early postemergence. We tested the efficacy of the aminopyralid for medusahead control in preemergence applications at three foothill rangeland sites in northern California. Treatments were applied in early fall 2009 and we evaluated the plots in May 2010. Our results...
- Author: WSSA
- re-poster: Brad Hanson
A quick repost this morning of a recent Weed Science Society of America (WSSA) press release about online databases and smartphone apps for tracking invasive weeds.
Technology that allows integration GPS coordinates and automated (or semi-automated) managment of huge, constantly changing datasets is evolving quickly. The ability for non-technical weed managers to use smartphones to monitor and even help map the location and movement of invasive weeds may allow new opportunities to identify invasions while they are small which can significantly increase the chances for successful eradiction or economical management. Pretty cool stuff!
- Author: Wendy West
The most effective, economical, and ecologically sound method of managing invasive plants is to prevent their invasion in the first place. Resources can be spent most efficiently on proactive activities that focus on stopping the movement of plant seeds and other reproductive parts to new areas.
One way that invasive weed seeds and root fragments can be moved is in hay and straw used for animal feed and bedding or in materials used for erosion control.
Seeds can also be transferred in animal manure if the animal has recently ingested invasive plants in infested feed or while grazing. These seeds and plant parts can then reproduce and colonize a previously uninfested area --- and if left...
- Author: Guy B Kyser
Woolly distaff thistle (Carthamus lanatus L.) is a yellow-flowered, spiny winter annual native to Mediterranean and central Europe. It has become a problem recently in northern California and southern Oregon. Ranchers in Marin County are reporting populations of distaff thistle so dense that they crowd out grasses and native species. The populations appear to spread along an elevation gradient, maybe along cattle trails.
Organic growers have tried mowing distaff prior to flowering. This sets it back, but is not a long-term solution – not to mention the difficulties of mowing on steep hillsides. In one area, ranchers conducted a prescribed burn in June, which prevented thistle from producing any seed...
- Author: Douglas J Munier
Previously in this blog Brad Hanson discussed some of the research Kent Brittan (UCCE Yolo) and I have done with Roundup Ready canola as a crop and then evaluating it as a weed because of its seed dormancy characteristics. We published an article on the weediness potential of Roundup Ready canola in California this past January in the Journal of Environmental Science and Pollution Research.
Here's the abstract from the article:
Abstract: Canola which is genetically modified (GM) for tolerance to glyphosate has the potential to become established as a new glyphosate resistant weed, thus reducing the effectiveness of glyphosate. Volunteer from dormant canola seeds produced thousands of plants per acre...