Sunday, December 18, 2011

Sagebrush


Weather: Monday’s snow landed on the snow still here from a week ago; Tuesday’s rain didn’t wash everything away; temperatures have been too cold since to melt much; 9:43 hours of daylight today.

What’s still green: Juniper and other evergreens, rose stems, hollyhock, winecup, vinca, sea pink, coral beardtongue, gypsum phacelia, snakeweed, strap-leaf aster leaves.

Still green plants, like gypsum phacelia, seem to peak through snow first, perhaps because they generate heat from below that adds to effects of the sun above.

What’s red/turning red: Cholla; branches on coyote willow, apples, apricots, spirea and raspberry; leaves on red hot poker, coral bells, small-leaved soapwort, pink evening primrose.

What’s blue or gray: Piñon; leaves on four-winged saltbush, snow-in-summer, pinks, yellow alyssum, golden hairy and purple asters.

What’s yellow-green: Branches on weeping willow; arborvitae beginning to bronze.

What’s blooming inside: Aptenia, asparagus fern, zonal geranium; buds on Christmas cactus.

Animal sightings: Small birds.

Weekly update: The day before Thanksgiving, I wandered out toward one of the badland formations for a closer look at junipers I’d seen for years from my back porch. I found them growing in an allée bordering a wide stretch of ground bared by flowing water.

Having gotten that far, I thought why not start up the water path towards the sedimentary cliffs themselves. Bunch grasses were dark and dormant, but Gypsum phacelia was green everywhere.


Then I saw something I’d never seen before in this area, a very low sagebrush. Soon after, the alkaline loving phacelia disappeared, and more sagebrushes sprawled about, exploiting, if not directing, the movement of water.

These plants had the shorter, wider three-lobed leaves and branching habit of the wyomingensis subspecies of Artemisia tridentata found in this state in Rio Arriba and Taos counties.

The other big sagebrush subspecies, tridentata, with longer, narrower three-toothed leaves and a central trunk, is also found in Rio Arriba and Taos counties, but also in San Juan county to the west. It doesn’t grow in Santa Fe or Los Alamos counties, but in Sandoval and McKinley to the west. It isn’t around Albuquerque, but in Valencia and Torrance counties to the south.

While I associate sagebrushes with the Taos plateau, Frederic Clements warns their dominance is recent, the likely consequence of overgrazing the original grasslands in the late nineteenth century.

Like the badlands, where remains of ancient horses and camels have been found, the Artemisia genus appeared sometime in the Miocene when grasses were emerging. Clements believes the two have had an antiphonal relationship since, with grasses appearing in wet periods and sagebrushes dominating when the climate dried.

In historic times, he thinks the range of sagebrush was limited to desert areas where its roots penetrated deeper than those of the more common grasses. Most of the native groups who used the plant, mainly for medicine, live in the dryer northwestern part of the state, the Hopi, Zuñi, Navajo and Apache.

Tewa speakers used the dark woody branches as fuel when nothing better was available, say “on the journey from San Juan to Taos.” They used the leaves, which they could have brought back, to treat indigestion, flatulence, coughs and congestion.


The gray leaves have a bitter taste which discourages many animals from eating them, except during famine times. The nitrogen containing monoterpene oils that make them medicinally useful attack the digesting bacteria in animals’ stomachs. When sheep or cattle were abusing a stand of grass, sagebrush had a competitive advantage.

About the only wild animal who can digest the composite is the pronghorn, whose ancestors emerged in the post-Miocene when “the lower valleys appear to have been primarily clothed in spruce parklands, marshy meadows, or sagebrush (Artemisia) steppe with subalpine conifers and shrubs dominating the coarser sites.” The modern animal evolved when tree and grass savannas were alternating with shrub steppes during the warm periods between glacial advances.

William Dick-Peddie suggests the mechanics of domination are those of erosion. When grasses are eaten to stubs, water flows over the land, rather than into it. Juniper sprouts in depressions where water collects, while sagebrush nestles in the slightly elevated spots between.


I have no idea from whence came the seeds of the shrubs I saw or if they had taking advantage of the past season’s drought. Seed can last at least nine years under the right conditions, but it first has to be in the area. I haven’t ventured past the cliffs yet to see what grows beyond, so I don’t know if there’s some indigenous source or if the tiny brown seeds were tracked in by hikers or ATV tires.

I waited twenty years to visit the junipers and badlands. No matter how intense my curiosity now, I have no choice but to wait until the snow clears enough so I can see where I’m walking.

Notes:Brown, David E. “An Evolutionary History of Pronghorn Habitat and Its Effect on Taxonomic Differentiation,” Pronghorn Workshop, 2006.

Clements, Frederic E. Dynamics of Vegetation, collected papers edited by B. W. Allred and Edith S. Clements, 1949.

Dick-Peddie, William A. New Mexico Vegetation, 1993.

Moerman, Dan. Native American Ethnobotany, 1998, summarizes data from a number of ethnographies.

Robbins, William Wilfred, John Peabody Harrington, and Barbara Friere-Marreco. Ethnobotany of the Tewa Indians, 1916.

Tilley, Derek J., Dan Ogle, Loren St. John, and Brock Benson. “Big Sagebrush,” USDA Natural Resources Conservation Service plant guide.

United States Department of Agriculture, Natural Resources Conservation Service. New Mexico county distribution maps for Artemisia tridentata subspecies.

Photographs: All were taken near the local badlands, 23 November 2011. Gypsum phacelia in lower left hand corner of second picture.

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