Posts Tagged: John Roncoroni

Unwelcome weed 'stinkwort' spreading quickly in California

UC Cooperative Extension experts are advocating for aggressive control of invasive stinkwort to prevent it from becoming an established California weed, reported the Sacramento Bee. Joe DiTamaso, UCCE specialist in the Department of Plant Sciences at UC Davis, said he believes CalTrans will have to treat stinkwort as an invasive of high and unique concern if it has any hope of controlling its spread.

Stinkwort made its first California appearance in 1994, but remained quite rare until the mid-2000s, when it began spreading rapidly. Stinkwort is now found in 36 of the state's 58 counties, particularly along roadsides.

"If it gets a major foothold and produces millions and millions of seeds, then the seedlings will grow and they can form a carpet," DiTomaso said. "Then it would block light and prevent the growth of more desirable species – like native plants. It will out-compete them, and that is a concern."

Another troubling aspect is that the weed has been seen in vineyards, said John Roncoroni, UCCE advisor in Napa County, a weed science expert.

"I've seen it on the roadsides in Napa, and it's just encroaching into the vineyards at Napa Valley College," he said.

Local collaboration is one secret behind excellent Napa Valley wine

One reason the Napa County wine industry is so successful is its commitment to working together, wrote Paul Franson in an op-ed piece that ran in the Napa Valley Register today. Franson credits frequent industry meetings in the area, where a wealth of information on grape growth and wine production are offered.

A recent meeting he cited was a field day last month in which John Roncoroni, UC Cooperative Extension advisor in Napa County, took two groups through the Huichica Creek Demonstration Vineyard in Carneros to teach attendees how to identify weeds that commonly occur in vineyards.

Other local organizations that bring together local grape and wine producers are the Napa County Agricultural Commissioner's office, the Napa Valley Grapegrowers, Napa Sustainable Winegrowing Group and the UC Davis Department of Viticulture and Enology.

"It’s no wonder that Napa Valley growers get the highest prices for their grapes in the state. They learn how to grow the grapes better," Franson wrote.

UCCE helps organic farmers confront weed control challenges

Organic weed control in orchards is far more difficult than conventional weed control, reported the Daily Democrat. The story was written by Bob Johnson for AgAlert.

The most effective organic approach to weed control is a combination of cultural practices and organic herbicides, said John Roncoroni, UC Cooperative Extension advisor in Napa County, at a pear weed control field meeting.

"This is the wood mulch from last year," Roncoroni pointed out at the field day. "As you can see, the grass is growing on the edges, but it's held up pretty well. This is after a year, but it will break down."

Roncoroni is testing the use of spot applications of organic herbicides in combination with mulches.

"Bindweed is pushing through the wood chip mulch," Roncoroni said. "The mulch is a foot deep, but the bindweed rhizomes are six feet deep."

Rachel Elkins, UCCE advisor in Lake and Mendocino counties, also spoke at the field day. She advised cleaning up weeds conventionally and then converting orchard ground management to organic methods.

"You shouldn't have any weeds within two or three feet of young trees," Elkins said. "It's like growing two crops - you need enough water and nitrogen for the trees and the weeds.

Yuba-Sutter almond harvest prices better this year
Ashley Gebb, The Appeal Democrat

The 2012 almond harvest is expected to be smaller than last year for some farmers, but hopes are for higher prices.

"The crop is not all the way in, so this is strictly rumor, but it seems the crop is a little bit off so price seems to be up a bit, which is good for growers," said Franz Niederholzer, UCCE advisor in Yuba and Sutter counties. "I'm not sure where it will work out with increase in price versus loss in income for reduced yield."

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