Carson-Iceberg Wilderness

Folger Peak from the Carson-Iceberg Wilderness.

After a hot California summer (one for which I was admittedly away for a decent portion), fall appears to finally be here. There are cooler temperatures in the Central Valley and day length is noticeably shorter.

Last weekend I ventured to the crest of the Sierra for a short excursion into the Carson-Iceberg Wilderness, one of the more northerly of the string of wilderness areas, national parks, and national monuments that protect much of the Sierra Nevada. The Carson is south of the Mokelumne Wilderness and north of Emigrant Wilderness and Yosemite National Park. It straddles the crest of the mountains that Muir called the “Range of Light”, incorporating part of the Humboldt-Toiyabe National Forest to the east and the Stanislaus National Forest to the west. The name of the wilderness derives from an early California settler (Kit Carson) and a unique rock formation within the wilderness (named Iceberg).

Map of wilderness areas in the Sierra Nevada
range. Map from sierrawild.gov.

I hiked into the wilderness with B from the Tryon Meadow trailhead. The trail was not very distinct in places, and therefore probably not frequently used, but obvious enough to not get steered too far off course. It passed through lightly dense forests of pine and firs, crossing a few very tiny streams. Some remnant patches of snow lingered on the western flank of Folger Peak, but the evidence of the very wet 2016-2017 California winter was otherwise gone.

We ended the hike at Milk Ranch Meadow, a lovely expanse of sedge-dominated wetlands occupying a broad valley. The lush yellow-green Carex swayed with the mild gusts of wind. The air was cool, but there was a clear sky full of warming sun. Open water in the form of a small lake and even smaller ponds occurred within the Carex meadow, and the wetland itself had standing water.

I spent about an hour trying to photograph dragonflies busy with activity over the wetland. I walked out on to the white skeleton branches of a fallen tree that penetrated into the wetland like a decaying pier. There appeared to be three dragonfly species: a rarer black form, a smaller red species, and a larger blue species that occupied much of my time. The red species was relatively easy to photograph because it would land patiently on the tree branches. The blue species, however, was constantly in motion, hovering above the sedges for a second and then descending into the vegetation, then pairing with a friend (or competitor) to dash off to a new spot above the meadow. They moved nearly constantly, seldom landed, and often mid-flight took a sharp turn to move in a different direction, all aspects of behavior that made them a keen challenge to capture by camera.

The blue dragonfly species.

Wetland at Milk Ranch Meadow.

The wilderness and adjacent national forest had a variety of flowers in bloom, including a very abundant species of pink Sidalcea, blue lupines with large palmate leaves, Spiraea splendens, and yellow and blue asters. Ipomopsis aggregata showed off its flame red flowers, with a long floral tube and five sharp pointed petals.

The high Sierra had some signs of the approaching fall season like a few hints of yellowing branches on the otherwise green aspens. The abundant corn lilies (Veratrum californicum) with their poisonous leaves, growing in patches in open areas, were well on their way to senescence too. Snow apparently returned to the Sierra over the past few days, and while the initial dusting may melt, soon the high peaks will be blanketed again. In the fluctuating annual precipitation regimes of California, and the longer-term pressure of a changing climate, will this year being a return of drought conditions, another wet year, or something closer to the long-term average?

References

Wenk E. 2015. Wildflowers of the High Sierra and John Muir Trail. Wilderness Press, Birmingham, AL.

Wilson L, Wilson J, Nicholas J. 1987. Wildflowers of Yosemite. Sunrise Productions, Yosemite, CA.

The red dragonfly species.

Ipomopsis aggregata (Polemoniaceae) at left and Sidalcea sp. (Malvaceae) at right.

Incredible plants: ocotillo

A flowering ocotillo in the western Arizona desert,
April 2017.

Primary productivity in desert environments is low. Water is the limiting resource for desert vegetation, whereas sunlight is available in overabundance. Desert plants generally only attain relatively short stature, and either flourish in annual bursts of growth (when rains come) or grow slowly over years and decades, responding opportunistically to rainfall availability over the longer term. Plants like cacti or the iconic Joshua Tree (Yucca brevifolia) of the southwest follow the latter strategy. In the life cycle of the ocotillo, one of my favorite desert plants, this species sort of embodies a bit of both strategies.

Ocotillo (Fouquieria splendens) is indicative of the Sonoran Desert, the hot low-elevation deserts of southeast California, eastern Arizona, and northwest Mexico. In terms of growth habit, the plants are one of the larger of the woody desert species in the southwestern US, reaching up to 10 m in height. They may live a century or two.

Germination of a young ocotillo requires a significant summer rainfall event of several centimeters. Most young seedlings will succumb to drought, frost or herbivores. Survivors become larger and woody. The stems of adult plants have a mottled grey and black surface with furrows. Sharp grey foreboding spines are abundant all over the stems.

Ocotillo leaves are short, spoon-shaped, and of two types. The primary leaves emerge from a petiole (which when dried, becomes the numerous spines lining the stems), while secondary leaves emerge in clusters directly from the base of the spines of the primary leaves and don’t have associated spines of their own. Secondary leaves are produced episodically and gorw in profusion very shortly after a good rain soaks the soil. The plant doesn’t invest for the long-term in these secondary leaves, rather they are produced without a cuticle (allowing easy CO₂ uptake but making them susceptible to water loss). After a few weeks mining the soil for water, the plant sheds its temporary leaves and will go physiologically dormant during a subsequent period of drought. Dormant plants retain living cells internally, but shallow roots die off and secondary leaves are lost.

Bare stem (left) on a plant from Joshua Tree National Park, CA, Feb 2012 and secondary leaves (right) on a plant from Arizona, April 2017. 

Inflorescence, western Arizona, April 2017.

Ocotillo are placed in their own plant family, the Fouquieriaceae, a small group of woody species endemic to Mexico and the southwestern US. The family is believed to have evolved in the subtropics during the Miocene (5-24 mya). The species grows below 2500 ft and occurs from California and Baja California eastward to Texas. The species is not tolerant of freezing temperatures which may be one factor limiting its occurrence in the Mojave and Great Basin deserts to the north where winter-time frost is likely.

Flowers are produced on branch tips. From a distance they appear as red flames. Flower petals are up to 2.5 cm long and are fused into a trumpet-shaped tube. A tuft of red stamens emerges beyond the corolla extending the length of the flower. Hummingbirds enjoy the nectar produced by the flowers.

References

Baldwin BG et al. (eds). 2012. The Jepson Manual. Higher Plants of California. 2^nd ed. University of California Press, Berkeley, CA.

Munz PA. 1962. California Desert Wildflowers. University of California Press, Berkeley CA.

Pavlik BM. 2008. The California Deserts. An Ecological Rediscovery. University of California Press, Berkeley, CA.

Leaf-less ocotillo in the Sonoran desert portion of Joshua
Tree National Park, Feb 2012.