Welwitschia seeds!

The Welwitschia mirabilis plants at UConn produced abundant fully-formed cones for the first time, this past summer. On warm afternoons in midsummer, the mature female cones produced "pollination drops," or droplets of nectar at the end of hair-like extensions of the ovules. The male cones have nectaries, as well, which probably attract insect pollinators in the wild in Namibia.

I placed pollen from the males into the pollination drops of female cones for several days running back in July, and two months later the seeds are starting to mature. Some of the seeds are very light and thin, and are probably duds, but quite a few look like viable Welwitschia seed. I may plant a few now to see what happens, though it probably isn't the best time of year.

Female cones with pollination drops, back in midsummer.

Succulents of Coastal Southern California 2: Cacti etc.

Ferocactus viridescens var. viridescens overlooking the Pacific at Torrey Pines State Reserve.

Apart from the Crassulaceae (stonecrop family), the Cactaceae (cactus family) is probably the group of succulent plants that is most prominent in the flora of the San Diego area. The most frequently encountered cacti are Opuntia and Cylindropuntia species, the prickly pears and chollas. There are several species of each genus in the area, ready to stick unwary hikers with barbed spines and glochids. Some, like Opuntia littoralis, form impressive spiky clumps.

Opuntia littoralis among spring wildflowers at Torrey Pines.

Ferocactus viridescens looks a little out of place in the chaparral of the coastal regions; the genus is much more widespread in true desert, inland. This small barrel cactus grows mostly on open gravelly slopes, though I spotted a few plants under the scrubby vegetation that dominates the area. Ferocactus viridescens seems to be relatively rare, and getting more so: a botanist told me about a large population in downtown San Diego that persisted for many years on a steep slope amid the parking lots and hotel complexes, which was just recently wiped out by development.

The cactus genera Mammillaria and Bergerocactus are also represented in coastal SoCal, though I’ve never spotted them in the wild. The local climate is almost entirely winter-rainfall, and it seems like the native cacti in the area grow and flower mainly in the cooler part of spring. I suspect that they would do most of their growing in the summer sun if cultivated in a greenhouse in the Northeast, but it would be worth experimenting with keeping them active in the winter.

Yucca shidigera at Torrey Pines.

Yucca and related genera Hesperoyucca and Agave (family Agavaceae) are also encountered in the patchy remnants of the wilds of greater San Diego. Yucca schidigera, Spanish Dagger, is widespread in the Sonoran and Mohave deserts, as well as the chaparral. It branches from the base and grows into a good-sized shrub, often taller than a person.

Marah macrocarpus in a weedy hedgerow on the agricultural outskirts of Vista, Ca.

Marah macrocarpus, California Manroot, is a caudiciform plant in the squash family (Cucurbitaceae). Marah produces scrambling, leafy vines in the winter and spring, but the interesting part of the plant, from the perspective of the succulent-plant fan, is the massive tuber. In the wild, the tuber stays unseen deep underground, but caudiciform growers can raise their Manroots partially above ground for viewing. So to speak.

Mesembryanthemum crystallinum on the beach. Invasive, but pretty.

Finally, the beaches and freeway medians of Southern California are host to a wide variety of ice plants (family Aizoaceae). Most of these are introduced from South Africa, but at least one species—Carpobrotus aequilaterus (Sour Fig)—is most likely native. Some of the exotic ice plants, including Mesembryanthemum and other species of Carpobrotus, have become invasive weeds, sometimes even encountered in wild areas.

The alien Carpobrotus edulis, grown as a groundcover in Vista, California. The native C. aequilaterus is similar, but with violet flowers.

Succulents of Coastal Southern California: Dudleya

Dudleya pulverulenta on granitic rock in Vista, California, April 2011.

The San Diego area experiences some of the most agreeable weather in the world. It has a mild Mediterranean climate where frost is a rarity and unpleasant heat is almost as uncommon; for months on end the forecast is “morning fog in coastal areas, then sunny with a high near 80.” Given a little irrigation, a huge range of tropical and subtropical flowers and fruits will grow like mad. A breakfast of the most delicious oranges and avocados can be obtained by merely reaching up and plucking it from the trees. Southwestern California is a land of milk and honey.

All of this is common knowledge, and as a result there is hardly an acre of land in coastal Southern California that hasn’t been converted to houses, strip malls, roads and farms. But here and there, one can find remnants of the original scrubby chaparral vegetation, which includes some interesting succulent plants.

Plants from the genus Dudleya are the characteristic succulents of the coastal chaparral. Dudleyas are rosette plants with succulent leaves, which often resemble Echeveria. In some ways, Dudleya is the winter-rainfall climate equivalent of Echeveria (which are summer-growing plants), although the two genera are not closely related, with Dudleya falling out near Sedum in recent evolutionary studies of the family Crassulaceae.

Dudleya edulis (left) and D. pulverulenta (right) on the beach at Torrey Pines.

The most common Dudleya in the vicinity of San Diego is D. pulverulenta, the Chalk Rose, which favors rocky slopes and can occasionally be found growing in road cuts. Chalk Roses can be stunningly beautiful plants, waxy white and bigger than dinner plates, with tall racemes of red tubular flowers that are pollinated by hummingbirds.

Dudleya edulis, or Fingertips Live-forever, is a more strictly coastal species with upright cylindrical leaves, like handfuls of string beans. Supposedly, the leaves can be eaten as a raw or cooked vegetable. Another species that seems to be most frequent on the coast, though it can occur inland on mountains, is D. lanceolata, which looks a lot like a greenish, pointy-leaved Echeveria.

Dudleya lanceolata at Torrey Pines. The Martian weed around the Dudleya is Crassula connata, a tiny winter annual.

The rarest Dudleya of San Diego County is D. blochmaniae ssp. brevifolia, which is found on a handful of sites near the ocean, growing on patches of open ground among pebbly, iron-rich concretions. It is a tiny plant, with globular leaves only a centimeter or so long, which blend in well with the dark concretions. It only grows in the winter and spring, and dies back to a subterranean tuber in warm weather. Fortunately, the primary population of D. blochmaniae ssp. brevifolia is protected within Torrey Pines State Park.

Dudleya blochmaniae ssp. brevifolia, getting ready to flower in April at Torrey Pines.

Dudleyas hardly seem to be cultivated at all by C&S people on the eastern seaboard, possibly because they are strict winter-growers, which can be tricky to accommodate outside of Mediterranean climes. They don’t seem to be too difficult, though, if they can be given plenty of sun and a fair amount of water in the cooler months, and a warm, dry summer rest. Water can accumulate among the waxy leaves of species like D. pulverulenta, and this should be drained off in order to avoid rot. In the wild, the rosettes are often held near vertically against cliff faces, so pooling rain is not an issue.

I’ll have more on the cacti and succulents of Southern California in a future post.

Heterotroph Invasion

This summer has been a good one for mushrooms and other non-photosynthetic, non-motile denizens of my yard, possibly because of unusually wet weather up until a couple of weeks ago. First up, two species of Monotropa, a genus the Ericaceae (heath family), that look superficially like fungi, but which are actually flowering plants that rely on a more or less parasitic relationship with real fungi for their organic nutrient needs.

Monotropa uniflora, Indian Pipe.

Monotropa hypopithys, Pinesap. This species is relatively uncommon, and is associated with pine trees. Presumably, it parasitizes fungi that have a symbiotic relationship with pine roots.

Next up, three things from the fungal kingdom. I don't know from mushrooms, so if anybody has ideas on identifications, leave a comment.

This one is probably Boletus chrysenteron. It's alarmingly large, about 20 cm across.

Boletus sp.? This one is growing under Eastern Hemlock trees, if that tells you mycologists anything. [Edited to add: possibly Leccinum sp.]

This thing has pores on the underside of its cap, like the boletes, and is growing under White Oaks. I'm coming up empty on possible names with my mushroom book. [edited to add: probably Strobilomyces floccopus, the Old Man of the Woods.]

I've also had these hanging around the neighborhood, mostly at dusk in pine trees. I'm no zoologist, but I checked some books, and they are probably some kind of chordate. Definitely metazoans, at any rate.

Titan Arum in Full Bloom

The Corpse Flower is fully open and producing waves of cabbage-y, fishy odor right now, near 11:00 PM. These photos are from just before sunset, when the lighting was better, and the smell was potent but not quite as overpowering as it is at the moment. The weather has been pretty warm lately, and I think that has encouraged a strong flowering event this time, even if the inflorescence is a little on the short side (~5 feet). The spathe is further reflexed than in previous blooms, and the colors seem a bit brighter.