- Posted by: Gale Perez
The Western IPM Center's May 2017 newsletter just came out.
The IPM VIDEO OF THE MONTH is on a robotic herbicide sprayer that targets weeds.
- Author: Whitney Brim-DeForest
- Posted by: Gale Perez
From the UC Rice Blog ι April 25, 2017
BUTTE®, a rice herbicide, has received federal registration in the USA and will be available to California rice growers for the upcoming 2017 season. Gowan Company, along with SDS Biotech and Nissan have collaborated to bring this product to California rice growers.
BUTTE® is a granular into-the-water herbicide that combines two modes of action: an HPPD-inhibitor (benzobicyclon), and an ALS-inhibitor (halosulfuron). It is the first HPPD-inhibitor available to California rice growers. Since weeds in CA rice have widespread herbicide resistance,...
- Author: Cari Koopmann Rivers
- Author: Steve Orloff
- Posted by: Gale Perez
The weather pattern this year in the Intermountain Region of Northern California has been radically different from what we have seen the previous 4 years. In most years, high pressure usually moves in periodically sending Pacific cold fronts farther north and giving us periods of warm dry weather. However, this winter and so far this spring high pressure has not dominated and we have been continually bombarded by cold fronts.
The frequent rains this winter and spring has resulted in changes in the weed spectrum. One weed we have seen a lot more of in this area is bur buttercup. Bur buttercup (Ranunculus testiculatus) has been widespread this spring and in some cases dense populations have been...
- Author: Richard Smith
- Author: Steven Fennimore
- Posted by: Gale Perez
Spinach is susceptible to weed pressure because it is produced on high-density 80-inch wide beds with 18 to 42 seedlines. There is no opportunity to cultivate the bed top so all weed control is accomplished by managing weeds in prior rotations, cultural practices, chemical weed control or hand weeding. Clipped spinach is mechanically harvested and must be kept as weed free as possible to reduce hand weeding costs. In the recent UC publication, Sample costs to produce and harvest organic spinach (Tourte et al, 2015 http://coststudies.ucdavis.edu/current/ ) hand weeding costs averaged $440 per acre. However, weeding costs can easily exceed $1,000 per acre in weedy fields, and...
- Author: Whitney Brim-DeForest
- Posted by: Gale Perez
We talk about herbicide resistance all of the time in California rice, but how does it evolve in a field? Understanding how herbicide management selects for resistant populations is an important part of preventing the problem from occurring in your fields.
We have many weed species in CA rice that are confirmed to be herbicide resistant. The major herbicide-resistant species are late watergrass, early watergrass, barnyardgrass, smallflower umbrella sedge, ricefield bulrush (roughseed), sprangletop, and redstem. For this illustration of how herbicide resistance evolves in a field, we use redstem as our example.
Year 1, Beginning of season: A population of redstem is found in a...