Friday, September 17, 2010

Euro Moth Inspection

Yesterday, starting at 8:00 a.m. sharp, the Borra Home Ranch Merlot and Barbera vineyards on Armstrong Road were inspected for the European Grapevine Moth by a team from the joint Federal/State Emergency Program of the California Department of Food & Agriculture and the USDA.



Mandatory inspections are the result of the quarantine that was set up August 3rd when two male moths were discovered in traps near Kettleman Lane and Curry Road. A couple thousand of these orange traps containing female moth pheromones and sticky flypaper are hanging throughout vineyards to detect any unlucky adult males that might be flittering about.



A swarm of moth caterpillars nearly destroyed a vineyard in Napa last September and none of us want the same to happen to our Lodi vineyards.

The Home Ranch Vineyard, against the north side of the winery and tasting room, is within the quarantine area, whereas Borra’s Gill Creek Ranch, on the east side of Elliot Road north of Lockeford, just missed being in the quarantine area.

Wineries that harvest winegrapes and crush them all within the quarantine area may pretty much go about business as usual. Borra, however, has a good business in selling grapes to wineries across the country, and the only way to legally ship grapes outside of the quarantine is with a special Certificate of Quarantine Compliance from the inspectors.



As explained by inspector Vincent Hicks using a finger to draw a diagram in the dirt, the first – and probably most time-consuming step in an inspection – is to establish a grid to make sure a statistically significant sampling of grape clusters is taken to determine whether or not the moth is present in the vineyard.

Their “systems approach inspection” has a 95% probability of finding moth caterpillars – if they are lurking – based on a “hypergeometric table” that determines the sampling grid for the vineyard. (The statistics can get pretty involved.)



For the layout of the Home Ranch Vineyard, that meant that Vincent needed to mark with green tape every 15th row of vines, where 2 bunches would be cut from every third vine down the row.

Altogether, Borra’s Manuel and his helper snipped off 300 bunches into 5 gallon buckets for the team of 4 to inspect on a folding table out amongst the vines.



The inspection team went about cutting and teasing apart berries on the bunches, looking carefully for caterpillars or evidence of their presence, such as messy little poops or tiny silk homes in the middle of bunches that look like a spider webs.

Fortunately, the team didn’t find any evidence of the moth when they called it a wrap at around 10:30 a.m. All they found was “nothin’ but spiders,” per inspector Dave DeWall. “And there’s a lot of them,” added Vincent.



In fact, spiders and getting occasionally yelled at by upset growers are the chief on-the-job hazards of the inspectors, who work through 3 to 5 vineyards a day, with around 100 under their belts so far this season.

Had a suspicious caterpillar been found, it would have been shipped up to Sacramento for expert identification to be sure it really was a European Grapevine Moth. And if it were, then Borra and growers within a half-mile radius would be notified that if they wanted to move fresh-picked grapes out of the area, they would need to be fumigated. In that case the entire quarantine area may need to be enlarged as well.

If inspection teams keep coming up empty-handed, then when the 10 head scientists supporting the program meet in Napa during the beginning of November, they’ll recommend the quarantine be lifted sooner rather than later.

What impressed me was the kindness and respect displayed by the inspectors. More than once they asked what we wanted to do with the inspected grapes when they were done. They looked a bit surprised when I said, “Dump them.” Which lead me to explain, “If Lodi were getting $3,000 a ton, maybe we’d save them.”



Meanwhile, Markus now has three permits good for a two week period to ship fresh Borra Merlot and Barbera out of California. All he needs to do is slap a “diamond” label on the grape bins and include a copy of the certificate of compliance.

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