Sierra Azul

Saturday, 25 October 2014

The Sierra Azul open space preserve is said to have 24.4 miles of trail, and hiking all of them generally adds an overhead of 50%, so it was clear that I was not going to do all the trails here in one visit. Two, probably. It was raining — the first rain this season — and wonderful to get out into it. The faded, dusty colours brighten up and the world looks great. And there is no such thing as bad weather, merely inadequate clothing. Not a problem.

I parked at Lexington reservoir and hiked the figure-8 trails (well, I actually hiked a PG-rated 33 set of trails), as well as a 4-mile down and back side trip to Kennedy road parking. Total 19 miles, over 5000 vertical feet. Hard day, but it felt good in the coolth.

Because of the rain, I put my cell phone and car keys into ziploc baggies, and left the real camera at home. So there aren’t many pictures: the GPS receiver has a camera, probably not even as good as the cell phone. These are from the Limekiln quarry, across the canyon as I descended back toward Lexington reservoir at the end of the day.

Jacky and I dined at an Indian restaurant (street food: and indeed we ate on the street), then went to a performance of the SF chamber orchestra at a local church whose pews have been padded in the seat in compliance with the Geneva convention, but still torture the lumbar vertabrae. We lasted until the interval. A good day.

Sunday, 26 October

I had rather intended to do another killer hike today and finish off Sierra Azul, but decided instead to go to Windy Hill and chase broom. I had volunteered to work on the broom along the lower part of Razorback ridge trail. I had already suspected that there was some form of Ur-forest of broom uphill and upwind from the trailside manifestations, and in last Sunday’s visit, I speculated on the location, a clear spot visible in the aerial photographs on Google earth.

Today I thought I would try to reach the hypothetical eye of the broomicane, but I was unable to find a good way to get there. What I did discover is an old power line, possibly inactive: at least one pole had no wires on it. The comparatively open space under it was a hotbed for broom, but unfortunately, also for poison oak. I looked for broom, found a lot, removed a lot, until my enthusiasm waned.

When I got home, I checked the GPS track with Google earth. Today’s work is above. Alpine road goes uphill across the upper right corner of the picture; Rapley trail goes uphill more or less straight down the picture. Damiani creek from lower center to upper right. GPS track in blue, erratic because of unreliable reception in the  woods.

Google earth includes aerial photography archives. The oldest available photos of this area date from 1953. I overlaid today’s GPS track onto it for reference. As we see, there was a patch of open country at the time, where today we find a lot of broom. The 1953 resolution is good enough to show shadows of the trees, so if there was ever a house in the clearing, it was gone by 1953.

I traced the outline of the open space in red and overlaid it onto the 2014 photo. Broom likes to get started in open areas, but it is perfectly capable of spreading into forests, which seems to be what is going on here. It is clear that unless this Ur-forest can be controlled, there will be a rear-guard action along the trail, continuing forever.

Today’s adventures. Check this space to see whether I managed to avoid the poison oak.

Tags: Sierra Azul open space preserve, Windy Hill open space preserve