Last fall, the County Agricultural Commissioner found evidence of Gypsy Moths in the Ojai Valley.A quick google search turned up this:
The gypsy moth is a pest that was imported into the United States in 1869 in an experiment to produce an improved silk producer. Once it escaped, it established in the New England states and has since defoliated forests, killed trees, and created great nuisances in urban areas. The greatest feeding damage is done by older caterpillars during the last two weeks of June, sometimes making it appear as if trees are stripped of leaves practically over night. ...almost everyone has some level of concern when gypsy moth caterpillars cause noticeable defoliation of trees, drop their frass (feces) on everything under the trees, or when the hairy caterpillars begin to crawl over everything in sight. At this point, people are willing to spray almost anything that they think will eliminate these caterpillars from their daily routines.
So, how can people avoid coming into contact with synthetic pesticides, yet control the gypsy moth? One answer is to use products derived from a naturally occurring, soil dwelling bacterium, called Bacillus thuringiensis, or "BT" for short.
This week the Agricultural Commissioner had plans to spray BT (Bacillus thuringiensis) a naturally occurring bacterium that produces a crystal protein toxin that kills the cells lining the insect gut. However, local residents, alarmed by information from Pesticide Free Ojai, have been refusing access to their property. Without this timely control, before the moths hatch in the coming weeks, the Ojai Valley's precious native oaks could be devastated. And with climate change upon us, the native shade canopy in the hot arid Ojai valley could be irreplaceable.
The controversy: http://www.ojaipost.com/2009/03/do_we_really_need_more_pestici.shtml
Update: State gets court order to spray for gypsy moths: Escorted by law enforcement, five agriculture crews try to stop moth's spread with pesticide
http://www.ojaipost.com/2009/03/the_war_on_gypsy_moths_2.shtml
http://www.venturacountystar.com/news/2009/apr/02/moth-spray-intrusion/
More info:
BT in Organic Gardening: http://www.dirtdoctor.com/view_question.php?id=184
CA Dept of Food and Ag: http://www.cdfa.ca.gov/phpps/gypsymoth/
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