Wednesday, November 16, 2011

Saratoga Gap and Travertine Spring

And sudden oak death

Fog bank out at the coast
This area of California is not noted for having a really striking fall. Many of the more suburban areas have lots of carefully planted and manicured trees that display fairly nice color, but that never really impresses me. What I really love is displays of natural growth. I always look forward to perusing photos from my flickr contacts, and checking out blogger content from other parts of the country. To some extent I can live vicariously through them when I can’t get away. That’s the beauty of online photo sharing and blogging. I enjoy great photos from places like the eastern Sierra, Pacific Northwest, and various locations back east, that are all very impressive without even leaving home. But what I really look forward to the most is to get outside, and there are areas around the south bay that do have their own unique quality when fall come into full swing. So that was my goal on a foggy and chilly Saturday morning. The areas around Saratoga Gap and along the southern skyline region have lots of big leaf maple, alders, and deciduous oaks that help to give the fall season a special character, even if you couldn’t really make a post card out of it. The cooler air and increased moisture content play a role too as the shades of green in the mosses and lichens really begin to display vividly, popping out in contrast with the orangey brown of the mulching leaves. The coastal fog rolling in overnight inducing the natural drip system pattering a rhythm on the forest floor provides a nice backdrop to the grayish mist as it floats like an apparition amongst the darkened shapes, and attenuated light.

Deciduous Oaks near Saratoga Gap
As I arrived at Saratoga Gap, I had noticed a temporary sign posted at the trailhead going north from the junction of highways 9 and 35. It had a MidPen logo on it, and provided a brief announcement of a new grant funded oak protection project. There has been an ongoing war being waged between scientists and Sudden Oak Death (SOD) since the mid 1990s in this region, as well as many other areas of California, and part of Oregon. MidPen and the CCC are teaming up to implement the latest front in the war to save California’s heritage oaks. This project involves the removal many California Bay trees from peninsula open space preserves, which did not make much sense to me at first. After all, the California Bay is a native tree species that has co-habited within the coastal range amongst many oak species for millennium. The Native Americans used the leaves for various remedies including headache relief. I have heard a lot about SOD in recent years, and we follow the guidelines for cleaning footgear and staying on trails, but I did not understand about removal of bay trees. The sign at the trailhead does not provide a lot of information, so that compelled me to do a little research of my own in order to better understand the situation.
According to the most reliable scientific studies, SOD is caused by a pathogen which can be classified as water borne mold called Phytophthora ramorum. The pathogen spreads in the form of spores which are born in the wind or by rain. SOD needs an unwitting host which harbors the disease, but does not die from it. The California Bay (Umbellularia Californica), also called California Bay Laurel, Pepperwood, Spicebush, Oregon Myrtle, and other names, have been discovered to be the primary vehicle to spread the disease if they are located within 15 feet of an oak species. This is why this new project has been initiated to remove bay trees that are within close enough proximity to be a threat to vulnerable heritage oaks. This is not the first project of this kind. This article in SFGate describes a similar project that was carried out last July. The following quote from that article identifies the California Bay as a major culprit in spreading SOD.
"The research showed that bay trees are responsible for the spreading of the disease," said biologist Cindy Roessler, the open space district's senior resource management specialist. "If you have a bay tree within 15 feet of an oak tree, that oak tree has a much higher chance of getting the disease."
The seriousness of the situation can be underscored by the following quote from the same SFGate article.
“Scientists have discovered that California bay laurels are the prime harborers of the microscopic spores, which are dispersed in the wind and rain. Arborists and ecologists are afraid that if the tiny marauders aren't stopped, California's golden hills could be denuded of its signature live oak trees. As it is, experts predict that as many as 90 percent of California's live oaks and black oaks could die within 25 years.”

This MidPen document from their website describes an earlier bay tree removal project from 2008. Here is a quote from that document.

“The California bay tree has been identified as a main transmitter of sudden oak death
because it hosts the pathogen on its leaves, but is not killed by it. Spores of P. ramorum
spread from the California bay tree leaves to nearby oak trees, which develop trunk
cankers and die.”

And I will offer one more quote from an article posted to the UC Davis Integrated Pest Management Program website.

“Research in California forests has shown that the greatest predictor of P. ramorum canker on oak is the presence of California bay laurel (Umbellularia californica). Pathologists believe P. ramorum drips or is blown down onto oak trunks from neighboring bay leaves when it rains. Once on the oak trunk, P. ramorum uses natural openings in the bark to colonize the bark tissues, killing cells and clogging water and nutrient transport vessels.”

I could go on, but the science gets really heavy from here, and that's a little beyond my scope. However, it is clear that there is no equivocation from the scientific community on the bay tree removals as being a logical step in order to help arrest the spread of SOD. For more detailed information you can visit the California Oak Mortality Task Force website. Given all the research data and public announcements that I found, I am actually amazed that I had not been more aware of this connection between the bay trees and SOD. I had to get this off my chest because I love bay trees, and I hate the idea that some of them must be destroyed, but this is indeed war, and I am in full support. If I only had more time I would volunteer my help.

San Lorenzo Headwaters
Now back to the hike. Oh, that’s right! I was on a hike. I hiked north on the Skyline Trail making my way through the greyish mire drifting lazily along the ridge tops to the crossover of highway 35 and into Long Ridge OSP. I turned south again using the Achistaca Trail to take me back to the crossover of highway 9, and down to the Saratoga Toll Road Trail. After that I was basically doing the same hike I had done a couple of weeks ago using the Toll Road to get to Travertine Spring Trail. With the progression of the fall weather, I was keen to visit areas with thick populations of the deciduous trees in order to explore the signs of seasonal change.

As the trail descended down toward the headwaters of the San Lorenzo River the fog thinned out into intermittent sunshine. This was on of those odd days when the fog was primarily up high. I was having a really great time checking out, and enjoying the sights, sounds, and even the smells of fall until reaching Castle Rock where I encountered a really large group of hikers that were taking a break around the trail camp. I immediately was thinking that I should really try to get out ahead of them just in case this huge mob of humanity was going to take the Trail I wanted. I was planing to use Loghry Woods Trail to get back to Skyline, and I did not want them to wind up becoming a walking, talking, trail blockage for my assent back to the ridge. I’ve had that happen before with large hiking groups, and it’s really annoying when they don’t have any sense of trail etiquette. Plus their noisy clamor scares away all the wildlife. I decided to make use of the pit toilet there as it was the only one around for miles, and then take off. But when I got finished, lo and behold, there they went en masse down the trail, making a huge racket, in the direction of the junction I was planning to use. And sure enough they began making the turn onto Loghry Woods Trail. Incredulous of my luck, I decided to just hang out around the trail camp for about 30 minutes to let them get well ahead, hoping that would be enough that I would not see them again. Quiet time is good I kept telling myself. The ploy worked, and the rest of my hike was just as pleasant as in the morning. Surely there must be a way to keep Castle Rock open. If this park actually closes, that will severely degrade the trail connectivity of this area. You can visit my photoset on flickr to see some pictures, and see a track log on EveryTrail.

Click here to visit the California Oak Mortality Task Force website
Click here to see MidPen's Sudden Oak Death fact sheet
Click here to download a Guide for Recreational Users from the California Oak Mortality Task Force


Katie (Nature ID) said...

Great post! I sent a link to Cindy. Seems this year the fall colors weren't as spectacular across the blogosphere as last year. Interesting about CA bays and SOD. I'm going to have to check out your links, because friends' have property down the coast where both oaks AND bays are dying. Now I understand why so many bay trees were being inexplicably cut at Mt. Madonna last winter. I'm with you on trying to stay clear of large hiking groups. So often they seem oblivious to the fact they're out in nature.

Katie (Nature ID) said...

Oops. Brain freeze. It's tanbark oak that is dying and being cut, not CA bay.

Cindy said...

Randy of Waypoints: a friend pointed me to this post when she saw me quoted. Thanks for spreading the word about about Sudden Oak Death and what's being done - you ARE doing something to help by sharing what you see and learn. Managing public lands is complicated but I find it heartening when people like you understand why we are removing a select set of bay trees to protect the huge oak trees, and to hear you enjoy these natural areas. Your description of our drippy, foggy green fall colors is perfect. Also, gorgeous photo of the creek. Enjoy! I look forward to hearing more about your hikes. -Cindy of Midpen and Dipper Ranch

Waypoints said...

Thanks Katie. Yes, I think getting the word out is very important, and especially to recreational users. I had heard about SOD, and the importance of not spreading it, but this business of the bay trees harboring spores was a total shock. I didn't know very much until I decided to do some research for this post.

Hi Cindy. I have read your blog before, and really enjoyed it, but I did not know that quote was from you. Great to have you stop by, and thanks for the encouragement.