Sunday, August 06, 2006

Evening Primroses

What’s blooming in the area: Apache plume, Illinois bundle flower, lance-leaf yellow brush, datura, buffalo gourd, stickleaf, white evening primrose, velvetweed, horseweed, white sweet clover, golden hairy aster, goldenrod, bigleaf globeflower, purple mat, bindweed, rose of Sharon, purple phlox, roses, sweet pea, faded bouncing Bess, heavenly blue morning glory, cardinal climber, pink evening primrose, trumpet creeper, silverlace vine, native and farmer’s sunflowers, pumpkins and beans. Hay cut in one field near orchards.

What’s blooming in my garden, looking north: Black eyed Susan, blanket flower, golden spur columbine, lance-leaf coreopsis, chocolate flowers, perky Sue, Hartweg evening primrose, fern-leaf yarrow, Mexican hat, yellow cosmos, creeping zinnia.

Looking east: Yellow evening primrose, garlic chives, California poppy, winecup peaked, floribunda (Fashion), small and large flowered soapworts peaked, pink bachelor button, coral beardtongue, hollyhock, Shirley poppy, sweet alyssum.

Look south: Zinnia, crimson rambler morning glory, sensation cosmos, blaze, rugosa and rugosa hybrid (Elisio); red hips visible on rugosa rose.

Look west: Perennial four o’clock, purple coneflower, white phlox (David), white spurge, frikarti aster, lead plant, catmint, blue flax, sea lavender, Russian sage, purple ice plant, caryopteris.

Bedding plants: Dalhburg daisies, marigolds, sweet alyssum, snapdragons, petunias, profusion zinnia.

Animal sightings: Hummingbirds, bees, ants, worm, grasshoppers on Russian sage, small snake near eastern bed. Quail crossed road with 20 young. Gopher killed a hollyhock and tomato.

Weather: Solid rain last night and this morning; gentle rain the night before as Chris dissipated in Caribbean. Earlier, the usual hot days, cloudy afternoons, cool nights, and no useful rain.

Weekly update: Evening primroses flourish this year. The tall yellow biennials are everywhere, the white cluster by the roadside, and solitary pink cultivars unfold in village gardens. In addition, velvetweed has established large colonies, and a willow leaved gaura sprouted at the road by my drive.

I haven’t driven along the other side of the river at the right time of day to see if the Hartweg and white primroses are blooming there as well. Calylophos hartwegii usually sprawl for a short stretch along the road through Santa Clara land.

It’s easy to ascribe their triumph to cool weather, but that doesn’t explain much with biennials. They had to have had their good season several years ago; I just removed unwanted plants that started growing before this year’s plants bloomed, and so must be last year’s offspring. This year’s flowers are from plants that grew between the grasshoppers of last summer and the invasion of Japanese beetles in 2003.

Botanists would tell us survival of the genes under extraordinary circumstances is a defining characteristic of the plant family Onagraceae. In 1929 Johansen theorized from chromosome counts that the family originated when two species crossbred and produced a fertile offspring that could breed with either of its parents. This created two related, but separate strains, the one tied back to the mother, the other to the father.

This is all posited to have occurred in the area of today’s intermontane southwestern deserts during the Eocene when the Rockies were first being formed and grasses were evolving some 34 to 54 million years ago. From there, Katinas, et alia, have traced the gauras, calylophus and oenothera eastward.

The primroses (oenothera) are the fifth descendant on the dominant side. Gaura emerged three stages later. And, they’re still propagating: Gaura neomexicana coloradoensis was first reported in 1895 around Fort Collins. A hundred years later, the population is still small enough to count in Colorado, Nebraska and Wyoming.

For nearsighted people like me who only see external characteristics, yellow evening primroses (Oenothera biennis) have flowers with four large petals on tall, rangy plants that can be recognized from the road. Less obvious from a distance, the four sepals curve downward and the eight anthers protrude. The sepals of the Hartwegs merely point away from the flower, but otherwise look the same.

Velvetweeds (Gaura mollis) have smaller flowers that advertise themselves by catching morning light a foot above their leaves. It’s necessary to stop to see the tiny white petals clasped by pink sepals which survive after the petals have fallen. The anthers are as obvious.

Insects apparently don’t have the same problems recognizing them, but the sepal embracement of the petals creates a funnel that hides the nectar from all but the most specialized pollinators like moths, hummingbirds and some bees. I never see any insects or birds near my flowers; in the early morning the bees are at the catmint and caryopteris.

Velvetweed has compensated for the difficulty of attracting insects by developing rhizomatous roots. It may have been forming colonies for years underground, unnoticed until conditions favored their fluorescence this summer.

The white primroses are itinerant. When they appear, and they don’t emerge every year, they may be 50' or a 100' from their ancestors. Several years ago, they shimmered above a field near San Ildefonso for about a week. I don’t know if drought prevented them from reappearing or hungry cattle.

My natives remain short, with serrated leaves and no more than two flowers at a time that curve into shallow cups. The ones along the road grow about a foot and have a number of flowers with petals that lay flat like a cross and sepals that fuse at the tips. Mine, with their reddish stems, usually begin blooming in May and are gone by 7am. The ones by the road with their whitish stalks open this time of year and last until mid-morning.

Perennial pink primroses (Oenothera speciosa) reseed within a few feet of their parents, usually nearer the walk where there’s more water, but so far they have not naturalized. The ones that edged a drive in the village did not recover from the Japanese beetles.

The fickelness of the onagraceae clan is one feature that makes them interesting to grow, or rather watch, since they disdain domestication. Only Gaura lindheimeri is currently attracting nurserymen like Baldassare Mineo and time will tell if anything he produces survives as well as the little white primroses that migrate every year.

Notes:
Johansen, Donald A. "A Proposed Phylogeny of the Onagraceae Based Primarily on Number of Chromosomes," Proceedings, National Academy of Science 15:882-885:1929.

Katinas, Liliana, Jorge V. Crisci, Warren L. Wagner and Peter C. Hoch. "Geographical Diversification of Tribes Epilobieae, Gongylcarpeae, and Onagreae (Onagraceae) in North America, Based on Parsimony Analysis of Endemicity and Track Compatibilty Analysis," Annals, Missouri Botanical Gardens 91:159-185:2004.

United States, Department of the Interior, Fish and Wildlife Service. "Proposed Threatened Status for the Plant Gaura Neomexicana ssp Coloradoensis," Federal Register 68 (56):14060-14065:24 March 1998.

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