It seems like the biggest hazard in recreating in California's many national, state, and regional parks is not making a campground reservation early enough. Last night, my family finally found a summer spot at a state parks campground in Mendocino - but not until mid August. That's the price we pay for such wonderful, inexpensive recreation within a few hours drive. That, and dirty, dirty clothes.
Of course, there are other issues to consider when we're out in California's forests. In the past week, I've noted three separate recreation-and-Sudden-Oak-Death mentions in local media: avoiding irritating pests (and SOD); campfire restrictions because of fire hazards (due to SOD); and trail closures (due to SOD). On top of that, the question of whether and how recreational visitors might spread the pathogen to new areas is one I get regularly. (Not to mention, it's already been a previous blog post of mine.)
Recreational users of our forests can spread Phytophthora ramorum - researchers have shown that they can carry clumps of infested mud along trails and back to their cars and homes (read the details here). The issue is how this level of spread compares to that of natural spread from the leaves of hosts in the forest, or from infected nursery plants trading around the globe. In any case, there are some simple sanitation steps that forest visitors can take to ease their minds and reduce their chance of spreading disease.
Ultimately, the recreation question is one I never get tired of because it shows me that people are concerned about our forests and our impacts on them. Any step individuals can take to protect our forests - from Sudden Oak Death or other threats - creates a sense of stewarship and connection that is larger than that single action. We owe it to ourselves and our forests to foster that sense of stewardship as much and as often as we can.
Make your camping reservations now!
I don't know if hitchhiking is so common anymore in our human communities, but it is a dispersal strategy that is alive and well in the plant world. Take a walk through Califorina's annual grasslands in the summer and check what's left in your boot laces and socks to see what I mean.
(Photo coutesy of http://waynesword.palomar.edu/plmay98.htm)
Even organisms that need not rely on animals for dispersal can still benefit from the worldwide movement of plants and animals. Take, for instance, the microscopic water mold Phytophthora ramorum, the pathogen that causes Sudden Oak Death and Ramorum foliar blight. Genetic analyses suggest that P. ramorum was introduced to California as an unknown, unseen hitchhiker on imported nursery plants. Now, in areas where it is well established in wild forests and landscapes, P. ramorum can hitchhike again, on the feet, hooves, paws, and tires of large animals.
As we enter spring, a time of planting in our gardens and venturing back out into our forests, it is good to remember the hitchhikers, seen and unseen, around us. Simple steps can help discourage the unwanted hitchhiking species around us, be they deadly plant pathogens or merely annoying weed seeds.
