Friday, July 21, 2017

California Spring Extravaganza 5. Torrey Pines State Natural Preserve

A typical specimen of Pinus torreyana overlooks the Pacific
On bluffs overlooking the Pacific Ocean, in one of the most densely populated
Camissoniopsis bistorta is a member of the Evening Primrose
Family (Onagraceae), with brilliant yellow flowers.  A
species of Cryptantha occurs with it.
parts of California, is an extraordinary natural oasis, Torrey Pines Natural Preserve.  It is the home of the main surviving population of the very rare Pinus torreyana, and a fine example of California's coastal chaparral community. In the spring, it lights up with a wonderful display of wildflowers, a little less gaudy than Antelope Valley or Anza-Borrego, but nevertheless filled with gems.  Some are similar to what can be seen at Pt. Mugu and other places to the north, but many that we saw only in this more southerly location. I've done my best to identify these plants correctly, but as usual will welcome corrections from those of you more familiar with California's amazing and diverse flora.
Ephemeral masses of a Cryptantha, probably C. muricata, fill
in around a more permanent beavertail cactus.
The sea dahlia, Leptosyne maritima (Asteraceae),
blooms abundantly in April on slopes in
the preserve.
A closer view of Cryptantha muricata (Boraginaceae)..
A beautiful red form of Mimulus aurantiacus (placed by some in the genus
Diplacus), Family Phrymaceae, is common at Torrey Pines.
Dichelostemma capitata, first seen in
Antelope Valley, seems to be everywhere
in California.
Acmispon glaber is a member of the Legume Family, Fabaceae.

Salvia mellifera (Lamiaceae), or black sage,
 is a common member of the chaparral
community in California.

Another form of Acmispon glaber has its
flowers more spread out.

The tarweed, Hemizona fasciculata

Saturday, July 1, 2017

California Spring Extravaganza 4. Cacti and cactus wannabees

Natural cactus gardens are common in the rocky slopes of Anza-Borrego.
No plants are more symbolic of deserts than cacti, and so they deserve a post of their own.  The cactus family consists of some 1750 species, almost exclusively inhabitants of the new world, and amply represented in the California desert.  So successful is the leafless, succulent habit of these plants, that regions of the world where the cactus family has not spread, have evolved their own cactus look-a-likes, or "wannabees" (want-to-be's) in the American slang.  In Africa, both the Euphorbiaceae and the Asclepiadaceae have produced their own cactus-like plants in great variety (see South Africa.8. Succulent Paradise, and others in the series).  And then there are the leaf succulents, Kalanchoe plus Aloe and their relatives in Africa, Agave, Sedum, in the new world.

The Ocotillo bush, Fouquieria splendens,
 superficially resembles a cactus.
In Anza-Borrego, a spectacular cactus mimic, ocotillo, is abundant. One can tell it is not a true cactus because after the rainy season its succulent stems are studded with small leaves, and the flowers are very different.  In the dry season, the leafless succulent stems could easily be mistaken for a thin-stemmed cactus.
In the rainy season, ocotillo sprouts small leaves.
Ocotillo flowers are produced in long racemes at the ends of the stems.

Ocotillo flowers are narrow-tubular, and pollinated by migrating hummingbirds that feed on their nectar.

The common beaver tail cactus in Anza-Borrego is
Opuntia basilaris.  A possible adaptive advantage
of the flattened stem segments is that the
noon-day sun strikes the surface obliquely.  This
may reduce the risk of overheating.
Like all cacti, the flowers of beaver tail cacti have
numerous petals and stamens.
Now for the real cacti.  Members of this family are leafless, except for some archaiec genera like Pereskia.  Actually, what were originally leaves in cactus ancestors were modified into spines, which occur in concentrated clusters along the stem,  Flowers in this family are large, with many petals and stamens, and an inferior (i.e. located below the petals and stamens) ovary with numerous seeds. So in flower, they are even more easily distinguished from their imitators. In Anza-Borrego several common growth forms are represented, including barrel cacti, cylindrical cacti, and beavertail cacti (having flattened, oval-shaped stem segments).

Mammillaria dioica is a small barrel cactus, and its stem is shaded by numerous long spines.

Cylindropuntia echinocarpa is one of the cylindrical cacti known as cholla.

Ferrocactus cylindraceus is another barrel cactus, here bedecked by a ring of flowers.
The flowers of Echinocereus engelmannii, a hedgehog cactus, resemble the beaver tail cactus that inhabits the same rocky slopes, but its stems are cylindrical. Photo by Gretchen Craig.

In this photo, the green stigmas of Echinocereus are seen in the center of the flower. Photo by Gretchen Craig.