To whom it may concern,

I have observed PG&E powerline subcontractor workers from across the country setting up large worker and equipment camps in several areas of Upper Napa Valley. With the increased attention to powerline safety, subcontractors from across the country are responding and hundreds of pieces of equipment including logging trucks, grapple trucks, boom trucks, bobcats excavators, worker trucks, trailers and workers with chainsaws, are staging here to begin the long, difficult task of increased powerline safety, vegetation management.

As a previous Agricultural Biologist and Pest Detection Specialist, I could not help but notice that such a sudden influx of machinery from across the nation poses a real threat of pest introduction and or spread of pests already established in Napa County. I have observed in Angwin alone trucks and equipment from 23 US states.

I believe the potential threat of introduction of pest species (plant, insect, pathogens) is a reality that our Agricultural Commissioner should be aware of and implement basic phytosanitary inspections related to pest exclusion and sanitation.

I have observed the following:

1. Equipment from Maine, North Carolina, Florida, Georgia, Alabama, Arkansas, Oklahoma, Missouri, Mississippi, Ohio, Illinois, North Dakota, Montana, Texas, Nevada, New Mexico, Arizona, Kansas, Virginia, New Hampshire, Iowa, Tennessee, West Virginia, parked in Angwin.

Mind you, these are working trucks that have been driven across the country and many are tagged ‘Disaster Response Vehicle Do Not Delay’. So what’s the likelihood that these vehicles were checked for Gypsy Moth Egg masses or other hitchhiking pests at the California Border Stations? At this time Federal and State Agricultural Officials are very concerned about the potential for the spread of Spotted Lantern Fly and Asian Longhorned Borer. These are not only forest pests but threats to our wine grape industry. Each truck or piece of equipment that is staged in Napa County should be inspected and tagged ‘clean’ similar to what we do for Eurasian Mussel inspections with boats.

2. In St. Helena, Calistoga, Deer Park, and Angwin, a collapse of oak species has been noted and the center hot spot seems to be one of the initial staging areas for PG&E equipment and wood debris storage in the Four Corners Area Of Angwin. Hundreds of dead and diseased oaks dot the landscape and PG&E subcontractors are routinely observed pruning or removing symptomatic trees with no sanitation practices in place. A laboratory analysis of causal organism is warranted so that local Agricultural officials can institute sanitation protocols with PG&E subcontractors/disaster crews if needed. When I asked one worker from Florida cutting into a dead oak tree about what steps were employed to minimize introduction or spread of pests he responded, “Pest? What’s a pest?”

3. Disposal of wood chips and other wood debris from clearings needs to be monitored. Pathogens are known to spread by movement of infected plant materials and some protocols to dispose of diseased debris must be established. I have noted disaster worker trucks with handmade signs: Free Mulch. Is there an established disposal location? Are dead or flagging/symptomatic trees being given away as mulch?

4. With the massive powerline clearings that are occurring, exposing previously shaded forest canopy floors down to bare dirt, the threat of introduction of weed species and the spread of noxious weed populations is very real. I observed grapple trucks repeatedly staged in a roadside turn out where a population of puncture vine Tribulus terrestris is established. Weed species can be spread via equipment and vehicles. Spread of noxious weeds may result in the necessity for increased herbicide applications and competition with desirable species in forest, residential and agricultural settings.

The cost of eradication of an introduced pest can be staggering. Forest pests often are here to stay (Dutch Elm Disease), while the cost of ongoing monitoring for pests eradicated is staggering (European Grapevine Moth, Mediterranean Fruit Fly).

Given the value of not only our agricultural products but also the importance of Napa County’s natural landscape to our economy, I wish to call the current situation to the attention of our Agricultural Commissioner, Farm Advisor, Resource Conservation District, Parks and Open Space District, Napa County Land Trust and industry organizations. The threat of pest introduction into Napa County and all of California is real, and exclusion and detection protocols must be established.


Kellie Anderson