From Sunday’s San Gabriels High Five run and hike.
Category Archives: nature|trees
Twilight Oak
From a run in Upper Las Virgenes Canyon Open Space Preserve (formerly Ahmanson Ranch).
Google search: $g(landscape photography)
Hill Dancers
From a run at Upper Las Virgenes Canyon Open Space Preserve (formerly Ahmanson Ranch). Note the hawk in the tree on the left.
Leaf Vein Networks
Who hasn’t pondered the intriguing network formed by the interconnected veins of a leaf? Like many apparently complex self-organized structures, there is a recognizable pattern, but the basis of the pattern is difficult to grasp.
Remarkably, research published in 2002 (S. Bohn et al., Phys. Rev. E, June 2002.) found that there is a simple relationship governing the angles between vein segments in the leaves of dicotyledons, and that this relationship is universal. The study also found that the observed vein angles can be reproduced using a simple force model.
Numerical analysis of leaf scans revealed that the angles between vein segments are directly related to the thickness of the segments. When the vein sizes are similar, the connection appears to form a three-way junction with the angle between the veins about 120 degrees. If the vein sizes are dissimilar, with one much larger than the other, the smaller vein joins the larger at about a 90 degree angle.
The photograph is of a leaf of a Fremont cottonwood (Populus fremontii) along Las Virgenes Creek in Upper Las Virgenes Canyon Open Space Preserve. It was taken on a run from the Victory trailhead on May 16, 2007.
Wally Waldron Limber Pine
A grizzled guardian of the San Gabriel Mountains, the Wally Waldron Tree stands defiantly astride an airy, rock strewn ridge, just below the summit of 9399 ft. Mt. Baden-Powell.
Perched on the brink of the mountain’s precipitous southeast face, the weather-sculpted Limber Pine is at an elevation and in an environment similar to the 4000+ yr. old White Mountain Bristlecone Pines. Burnished and hardened, the tree’s huge, gnarled roots anchor it firmly to the mountain, helping it to resist the whims of weather and time. The tree is estimated to be 1500 years old.
We had stopped to visit the tree part way through an approximately 23.5 mile loop from Islip Saddle. Our route had descended to South Fork Campground (4560′), before climbing back up to Vincent Gap and Mt. Baden-Powell. In a few minutes we would continue to Baden-Powell’s summit, and from there follow the PCT along the crest back to Islip Saddle. Here’s a Google Earth image and Google Earth KMZ file of a GPS trace of the loop.
Water Notes: The little stream on the Manzanita Trail about 1.5 miles from Vincent Gap was still running. The flow from Little Jimmy Spring was lower than normal, but still very reasonable. We did not detour to Lamil Spring.
Related posts: Vincent Gap – Little Jimmy Spring Out & Back, Complications, Heat Wave
Little Jimmy Spring Incense Cedar
This is the large incense-cedar (Calocedrus decurrens) mentioned in the post Snowless San Gabriels. It is located on a northeast facing slope near Little Jimmy Spring at an elevation of about 7460′ in the San Gabriel Mountains of Southern California. A vertical panorama better shows the size of this tree.
The scar from the 2002 Curve Fire can be seen on the left side of the tree. The black and white cap is about 7 inches wide and suggests a diameter of perhaps 70-80 inches. According to the species information in the FEIS database, in Southern California the largest incense-cedars generally have a diameter at breast height (d.b.h.) of 36-48 inches, but in the Sierra Nevada frequently reach diameters of 84 inches. According to the database, trees over about 200 years old are subject to dry rot, but large trees are often over 500 years old.
Related posts: Pine Mountain Juniper, Heat Wave, Lightning Tree