Southern California Vineyards Recover Thanks to Insecticide Applications

Grapevines Destroyed in 1999

Grapevines Destroyed in 1999

Temecula Today

Temecula Today

In 1999, about one-third of the vineyards in Temecula Valley, Riverside County, California were destroyed due to Pierce’s Disease which is caused by a bacteria transmitted to grapevines by an insect-the glassy winged sharpshooter. The disease seemed destined to spread throughout Southern California. However, research demonstrated that a carefully-timed insecticide application would prevent the sharpshooter from transmitting the disease to grapevines. As a result of this insecticide use, the wine grape industry in Southern California has recovered and is prospering.

“Twelve years ago a Pierce’s disease epidemic in Southern California wine grapes prompted a multi-pronged local, state and federal attack to contain the disease spread and find a cure or treatment.

Riverside County agriculture officials declared a local emergency in 1999 and 300 acres of Temecula wine grape vines were destroyed after they were found to be infested with the glassy winged sharpshooter.

Emergencies were declared, a task force was formed, and in 2000 $22.3 million in federal financial assistance was secured to reduce pest infestations and support research.

Research found that the Southern California epidemics were almost entirely the result of vine-to-vine transmission…. A protocol of applying one carefully timed application of a persistent systemic insecticide such as imidacloprid virtually eliminates the vine-to-vine spread.

Ben Drake is a Temecula-area wine grape grower and vineyard manager who began seeing problems from PD in the Temecula Valley as early as 1997.

We’ve found that if we apply (imidacloprid) at the middle to the end of May, before the sharpshooter moves out of the citrus and goes into the vineyards, we get levels of the material into the plant high enough that when the sharpshooter flies over from the citrus groves to try it, they just fly back where they came from. Or, if they feed long enough, it will kill them.

But just look at the Temecula Valley now to understand what’s changed: From 12 wineries in 1999, the Temecula Valley Winegrowers Association website today lists more than 50 growers and 34 wineries…. A thriving agritourism industry has developed…. Existing wineries are expanding and new ones are under construction or in planning phases.”

Author: Christine Thompson
Affiliation: Reporter
Title: Grape growers urged to remain vigilant against sharpshooter pest
Source: Western Farm Press. 2011-12-12. Available at: http://westernfarmpress.com/grapes/grape-growers-urged-remain-vigilant-against-sharpshooter-pest

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EPA Recognizes Value of Fumigants in Peanut Fields

Normal Peanuts and Black Rot Peanuts

Fumigated and Non-Fumigated

The disease known as cylindrocladium black rot (CBR) grows best in cool soils and is a major problem in the Virginia and North Carolina peanut regions. Entire pods may turn black and rot. The fungus may survive several years in the soil. Disease incidences in excess of 80% have occurred. The soil fumigant, metam sodium applied 8-10 inches below rows at least two weeks prior to planting has been the standard recommendation for control of CBR since 1985. Recently, the USEPA conducted a study of the value of metam sodium for peanuts and concluded that…

“Thus, the main benefit of metam sodium is that it permits cultivation of peanuts that would otherwise not be economically viable. …a large proportion of peanut acreage in the North Carolina-Virginia region depends on metam sodium simply to make production economically viable.”

Authors: A. Chiri, and T. J. Wyatt
Affiliations: EPA, Office of Pesticide Programs, Biological and Economic Analysis Division.
Title: Assessment of the Benefits of Soil Fumigation with Metam Sodium in Peanut Production.
Publication: U.S. EPA. (2007). Assessment of the benefits of soil fumigation with metam sodium in peanut production (DP#337490). Available at http://www.regulations.gov/#!home

Heavy Thrips Infestations in Virginia and North Carolina Cotton

Thrips have many hosts, including grasses, grains and alfalfa. Large populations often develop on these hosts and fly into cotton fields when the cotton seedlings are developing. Thrips feeding causes severe deformation and stunting of the developing cotton leaves. The Upper Southeast cotton region (Virginia and North Carolina) could be designated “Thrips Central” for the Cotton Belt. Jack Bacheler, a North Carolina Extension Entomologist, explains…

“With the exceptionally warm winter and good moisture levels, at this point it looks like thrips flights into cotton should be both large and early this year. … Our region has earned the distinction of having the highest levels of thrips and greatest potential damage to seedling cotton of anywhere in the U.S. In some tests, with the help of a microscope, we sometimes count as many as 200 to 500 thrips per 5 seedlings! That’s a “ton” of thrips, especially if seedlings are unprotected. So it’s probably not a surprise that Virginia and North Carolina have the highest ratio of surrounding host vegetation to small average cotton field size.”

“Over the past eight years, more than 85 percent of our cotton acreage has been over-sprayed [i.e. sprayed over] following a seed treatment. With the potential for thrips damage lasting up to 5 or 6 weeks after planting and seed treatments varying from about 2 to 3 weeks in their activity, a high percentage of foliar follow-up treatments for thrips is not surprising.”

Author: Jack Bacheler
Affiliation: North Carolina Extension Entomologist
Title: Heavy thrips populations anticipated.
Publication: Southeast Farm Press, April 18, 2012. Available: http://connection.ebscohost.com/c/articles/76291692/thrips-pressure-heavy-mississippi-cotton

Research Shows Importance of Insecticides for Sweet Potato

North Carolina is the country’s largest sweet potato producing state, totaling nearly half the entire production in the U.S. Wireworms, which live in the soil and feed on sweet potato roots, are the #1 insect enemy of sweet potato growers. Mark Abney, North Carolina State University entomologist, explains what his research has determined about the value of insecticide treatments for wireworm control…

“Abney was part of the multi-state project that ran from 2004-2007 and was designed to document which insects were major pests of sweet potatoes and begin the process of developing comprehensive IPM programs to best manage these pests. … ‘So, growers who don’t treat with an insecticide for wireworm control on sweet potatoes should expect 40 percent or more of their crop to be damaged by wireworms and for 17-20 percent of the crop to be unmarketable,’ he adds.”

Author: Roy Roberson
Title: Wireworm management a must in North Carolina sweet potatoes.
Publication: Southeast Farm Press. 2012. January 11.