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The restrictions, expected to be issued in early January, will affect millions of plants grown in California, Oregon and Washington, about one-third of the country's nursery plant supply. They will require inspection, sampling and possibly testing of all plants that could be hosts to the pathogen, Phytophthora ramorum, the cause of sudden oak death syndrome, before shipment across state lines. The disease has been spotted in 22 states.

Meanwhile, virtually NOTHING is done about plants imported from overseas.

You will note in the top photo: That is a riparian corridor with surrounding firs on the left and madrone on the right (the left side probably faces north or east). The dead trees are Lithocarpus densiflorus (tanoak). Oaks don't do well down in a wet shady gully like that, particularly shaded for part of the day by taller trees. They are as much victims of fire suppression and succession having allowed massive overstocking. That raised the average humidity, increased the duration of fog, reduced aeration, and increased accumulated and acidic litter (which would kill those trees eventually anyway when Armillaria gets into the cambium breaks caused by girdling roots due to the litter). Higher average humidity and shorter hours of sunlight greatly aid the disease in infecting a tree (tanoak is particularly susceptible because of its thinner bark than most oaks).

These species were selected over the last few thousand years having become accustomed to regular fire. Regular fires would have prevented the conifers from being so dense and shading that zone. Regular fires would have consumed the litter and provided those trees nutrition. There is no way that a stand now in that stocking density could survive a fire.

This disease started in Marin and Santa Cruz Counties, two of the most heavily regulated and overgrown counties in the whole state. I live in Santa Cruz County. Unlike my nieghbors, I have done the hard work of thinning my forests. In the seven years since Phytophthora ramorum was identified, I have lost ONE tree. The trees in that photo are more victims of how that land was managed than they are of the disease (which was likely imported from Europe with rhododendrons, btw).

Phytophthora ramorum produces spores. That means it is spread by birds. There is NO WAY any regulatory body is going to stop it now. All this action accomplishes is to kill a legitimate (although badly run) horticultural industry that we need for re-establishing native plants. The only way they could have prevented the disease was to take action on screening imports (particularly from Mexico), which is the one thing they don't do. So if that doesn't seem likely, ask yourself why.

I agree.

I own a 20ac nursery & garden center in southcentral Pennsylvania, and have been tracking it here for over 2 years with the Penna Dept of Ag, EPA and DER. Mostly confined to western PA, it is beginning to work its way east. Particularly aiding it are the last two wet years we've gone through in this region. The Plum Pox virus is another we're tracking.

More than 70% of my retail nursery stock - the rare, unusual and hard-to-find Jap maples and conifers - come from Oregon, and spring shipments will be impacted.

That said, there is nothing they can do to stop it now; the toothpaste is out of the tube.

There are several bio-terrorism/economic impact theories floating around Harrisburg, these days.