Sunday, October 09, 2011

Narrow-Leaved Collomia


What’s blooming in the area: Hybrid tea roses, Russian sage, silver lace vine, red yucca, datura, sweet pea, Sensation cosmos, French marigolds, pampas grass; grape leaves turning yellow.

Beyond the walls and fences: Indian paintbrush near chamisa, leatherleaf globemallows, blue gilia, clammy weed, white and yellow evening primroses, bindweed, ivy-leaf morning glory, scarlet creeper, goat’s head, bush pea, stickleaf, toothed spurge, prostrate knotweed, lamb’s quarter, amaranth, pigweed, chamisa, native sunflowers, snakeweed, spiny lettuce, gumweed, Hopi tea, áñil del muerto, broom senecio, golden hairy, strap-leaf, purple and heath asters, cockle bur, black grama grass; salt bush beginning to turn yellow.

In my yard, looking east: Winecup mallow, sidalcea, large-leaf soapwort, pink evening primrose, Rose Queen salvia, Shirley and California poppies, Maximilian sunflowers, tansy fading.

Looking south: Floribunda roses, reseeded and new Crimson Rambler morning glories; sweet alyssum, moss rose and zinnia from seed.

Looking west: Calamintha, sea lavender, lead plant, Silver King artemisia; skunk bush leaves turning yellow orange.

Looking north: Golden spur columbine, nasturtium from seed, Mexican hat, chocolate flower, blanket flower, yellow cosmos from seed, black-eyed Susan, chrysanthemum.

Bedding plants: Sweet alyssum, pansy, moss rose, nicotiana, impatiens, tomato; peppers turned red.

Inside: Aptenia, asparagus fern, zonal geranium.

Animal sightings: Hummingbird, harvester and small black ants.

Weather: Rain much of Friday night, snow in east and west mountains yesterday morning; 11:33 hours of daylight today.

Weekly update: The far arroyo goes back a couple miles from the ranch road. I don’t usually walk much farther than the section dominated by the high, hard right bank where the four-winged salt bushes creep up the base. If I do continue southeast, the base changes to the sorts of weeds I find along the road shoulder, pigweed, Russian thistle, sweet white clover, yellow hairy asters.

After that the bank drops, vegetation disappears and the rocks cross in what would be rapids if the arroyo were flowing. I can still see striations from water movements a month ago that haven’t yet dried and blown away.

From there the other bank sweeps out with a higher, hard edge, and the right bank slowly rises a few feet. In the area where the soft bank is only a foot high I’ve discovered a small section where late summer wildflowers bloom. Their seeds will occasionally settle in the ruderal section and a few will cross to land near the Russian olive at the ranch road, but if I want to see them I usually need to walk upstream a few weeks after the rain.

Narrow-leaved collomias were blooming there two weeks ago. A few plants were left last Sunday. I suspect I won’t find any when I wander out later today.

When you first come upon the flowering plant, you nearly pass it by as one more aborted purple aster. It has the same general habit, an isolated, reddish stem covered with dark, needle-shaped leaves, flowers at the ends. However, you soon notice they aren’t daisies.

When you stoop for a closer look you realize it’s a member of the phlox family. The five narrow petals fuse into long tubes that settle into dark green nests of individual retaining vials that persist after the corollas fall away, so eventually only the green shows. On some, the heads are full globes; on others they’re spread out like snapdragons or ladybells.

On a few plants, the leaves are long and luxurious. On others, they barely exist or have fallen away. On most in the arroyo, there are only a few reflexed lances alternating along slightly hairy stems.

In other parts of the Great Plains and in California, Dieter Wilken says the flowers are “white to pink,” but in Arizona he says they are “bluish violet to nearly white.” The local ones have light lavender petals and darker veins. Dark eyes dominate the centers, both from pigments in the petals and from the filaments. The anthers and tips of the stigmas are lighter colored.

In many places between the eastern edge of the plains and the Pacific coast ranges, the annual blooms sometime between April and August. With this year’s delayed rains, they didn’t get their chance here until September.

Adaptability seems one of the hallmarks of a plant Elmer Wooton and Paul Standley said was growing in “meadows in the mountains” of Tunitcha, Chama, Santa Fe and Las Vegas early in the last century. Al Schneider says it’s now common in the mountains of the Four Corners region.

When Wilken looked closely at two Collomia linearis populations from Larimer County in north central Colorado, he found more variation in external morphological traits from plants growing in a disturbed area than from those in an alpine meadow. Since the annuals can pollinate themselves, this means, so long as no environmental condition selects one genetic combination year after year, plants in any given location produce wide possibilities to survive whatever nature offers any particular year. Their ability to adapt is sustained.

Perhaps the oblong brown seeds provide some of the most useful adaptative mechanisms. When they’ve ripened, the capsules open to expel them. Sometimes, like this past week, that occurs when the ground is wet. The seed coat becomes sticky when it’s wet and the seed stays long enough to lodge where it landed, rather than being picked up again by the drying winds and dropped in some less congenial location.

In the arroyo, seeds from the primary population apparently have been sent downstream by either the wind or the rain. Only those that landed in areas where other vegetation helped trap moisture, the ruderal base of the high bank, the plants between chamisa and the Russian olive, have been able to germinate.

Next year, those isolated plants may expand their populations, or maybe other environmental factors will destroy their seed before the summer rains arrive. Presumably, they have the genetic variety needed to survive somewhere.

Notes:
Schneider, Al. “Collomia linearis,” Southwest Colorado Wildflowers website.

Wilken, Dieter H. “Local Differentiation for Phenotypic Plasticity in the Annual Collomia linearis (Polemoniaceae),” Systematic Botany 2:99-108:1977.

_____. “Collomia Nutt., Collomia” in Great Plains Flora Association, Flora of the Great Plains, 1986.

_____. Entries on Collomia and C. linearis Nutt., Jepson Flora Project website.

_____ and J. Mark Porter. “Vascular Plants of Arizona: Polemoniaceae,” Canotia 1:1-37:2005.

Wooton, Elmer O. and Paul C. Standley. Flora of New Mexico, 1915, reprinted by J. Cramer, 1972.

Photograph: Narrow-leaved collomia upstream on the arroyo bank in a slight breeze, 2 October 2011.

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