In summer 2015, USDA-ARS and UC Davis Dept of Plant Sciences set up a water hyacinth control study with California Department of Boating & Waterways. The goal of the study was to determine the best of several different surfactants to pair with an aquatic-use formulation of glyphosate.
Aquatic weed trials are tricky compared to terrestrial trials, because the test sites are three-dimensional and they move around. In addition, water hyacinth is free-floating. In order to establish secure test plots, we built floating 1-m2 quadrats out of PVC pipe, swim noodles, and construction fencing.
On 31 July, we anchored the quadrats in open water within a sunken island in the Sacramento delta. Quadrats were...
Do weed populations change during a drought? Does drought favor certain species? Does annual or perennial species matter? During this four year period of drought in California, have they changed? What are the populations of annual and perennial weeds? With a limiting growth factor, in this case water, weeds become more prominent and which of them will or could disappear?
In urban landscapes, where turf grass areas are being renovated, or in non-irrigated land that has been farmed, but furloughed, or in non-cropped roadsides or wasteland, are we seeing life-cycle species shifts? Or is it that we see a loss or decreased competitiveness of annual species, thus perennial species can be observed?
I will give the example of...
Reposted with permission from the January 2014 issue of "CWSS Research Update and News", a semiannual publication by the California Weed Science Society. Check out that issue for several other interesting research and extension articles. Take care, Brad
Control of Willowherb in California's North Coast Vineyards
- John Roncoroni, UCCE Napa.../span>
- Posted by: Gale Perez
Napa, Calif.—Last week John Roncoroni, a Napa County UC Cooperative Extension weed science advisor, held a field demonstration about the efficacy of herbicides newly registered for vineyard application. He had laid out 25 treatment plots and rated the herbicides for weed control in vineyards./span>
- Author: Carl E. Bell
- Re-posted by: Gale Perez
Tips on applying herbicides
The table below is from training that my colleagues Dr. Cheryl Wilen, Area Advisor, UC IPM; Dr. Milt McGiffen, Extension Specialist, UC Riverside; and I did in southern California at four locations in 2009/2010 with a total of 80 people that all had previous experience applying herbicides on invasive plants. This training utilized the 128th acre sprayer calibration method (more on that below).