Visitors 52
Modified 3-Jul-24
Created 1-Jul-24
36 photos
We start from the Sun Research Center, cross the dam, make our way through oak woodland up to and through the Blue Oak forest on the ridge, then out into the grassland. Mixed soil types underly the grassland – a little way in, we find serpentine soil, carpeted with native spring flowers, especially in the disturbed region along the dirt road. Hiking through the springtime dazzle, we turn south, toward the San Andreas fault and Skyline. On this gentle slope leading down to Corte Madera Creek, we find woodlands, chaparral, and grassland – the grassland carpeted with annual grasses brought by early Europeans, still green. We make our way down the creek, across the causeway bisecting the original unified Searsville Lake, and back to our starting point.
This ambitious afternoon walk is billed as a “pre-hike”, preparation for a later outing for our friends at the Peninsula Open Space Trust. We traverse much of the Preserve, observing many different ecosystems arising from varied soil types, slope and orientation, moisture and more. Here are a few highlights – we move too fast for a comprehensive catalog.
Water gushes beneath us as we cross the dam. In forested slopes above the lake, Warriors’ Plume, Fremont’s Star Lily, and Blue Witch Nightshade blossom; a spider lurks on the Warriors’ Plume. A Red-tailed Hawk circles; a California Scrub Jay keeps watch.
We pass through chaparral and Blue Oak Forest without incident.
The springtime bloom is well underway in the serpentine grasslands at the top of the Ridge. California Goldfields hug the road, extending in patches into the serpentine soil beyond. Purple Leptosiphon provide a contrast; an occasional California Poppy ventures out. Serpentine rocks, bluegreen in the afternoon light, protrude.
Beyond the margins of the serpentine soil, other native flowers share space with European annual grasses. Narrow-leaved Mule Ears attract varied insects. Blue-eyed-grass flourishes. Non-native Vetch attracts a handsome brown butterfly (ID help, please!).
Dropping down to the creek on Trail 10, we pass in and out of chaparral, oak woodland, and grasslands. New oak leaves shine in the sunlight, drawing the eye amidst a scene of contrasting shades of green: yellow-green new grass, fresh shining light-green deciduous oak leaves, and darker green leaves on Coast Live Oaks and many chaparral plants. Bluegreen California Sagebrush, conserving water. On the blue horizon, Skyline, covered with conifers.
Look closer: a caterpillar of the Variable Checkerspot Butterfly -- jet black with bright orange warning cones, sprinkled with white dots – browses on a mint. Predators avoid! An oak gall, stitched along the centerline, bright green shading to reddish-orange, occupies a branch – who ordered that? In the grassland, lupines. Above, blue sky with puffy clouds beneath a vast diverging pattern of whispy clouds.
Corte Madera creek flows slowly. Giant Trillium persists near former wetlands. Other flowers and seeds draw the eye – please let us know the ID if you can.
Deb, thanks for guiding this comprehensive jaunt.
This ambitious afternoon walk is billed as a “pre-hike”, preparation for a later outing for our friends at the Peninsula Open Space Trust. We traverse much of the Preserve, observing many different ecosystems arising from varied soil types, slope and orientation, moisture and more. Here are a few highlights – we move too fast for a comprehensive catalog.
Water gushes beneath us as we cross the dam. In forested slopes above the lake, Warriors’ Plume, Fremont’s Star Lily, and Blue Witch Nightshade blossom; a spider lurks on the Warriors’ Plume. A Red-tailed Hawk circles; a California Scrub Jay keeps watch.
We pass through chaparral and Blue Oak Forest without incident.
The springtime bloom is well underway in the serpentine grasslands at the top of the Ridge. California Goldfields hug the road, extending in patches into the serpentine soil beyond. Purple Leptosiphon provide a contrast; an occasional California Poppy ventures out. Serpentine rocks, bluegreen in the afternoon light, protrude.
Beyond the margins of the serpentine soil, other native flowers share space with European annual grasses. Narrow-leaved Mule Ears attract varied insects. Blue-eyed-grass flourishes. Non-native Vetch attracts a handsome brown butterfly (ID help, please!).
Dropping down to the creek on Trail 10, we pass in and out of chaparral, oak woodland, and grasslands. New oak leaves shine in the sunlight, drawing the eye amidst a scene of contrasting shades of green: yellow-green new grass, fresh shining light-green deciduous oak leaves, and darker green leaves on Coast Live Oaks and many chaparral plants. Bluegreen California Sagebrush, conserving water. On the blue horizon, Skyline, covered with conifers.
Look closer: a caterpillar of the Variable Checkerspot Butterfly -- jet black with bright orange warning cones, sprinkled with white dots – browses on a mint. Predators avoid! An oak gall, stitched along the centerline, bright green shading to reddish-orange, occupies a branch – who ordered that? In the grassland, lupines. Above, blue sky with puffy clouds beneath a vast diverging pattern of whispy clouds.
Corte Madera creek flows slowly. Giant Trillium persists near former wetlands. Other flowers and seeds draw the eye – please let us know the ID if you can.
Deb, thanks for guiding this comprehensive jaunt.
Dan Quinn