Sunday, April 21, 2013

Rocks and Roots

Weather: Intermittent high winds; last rain 4/09/13; 13:10 hours of daylight today.

Cold temperatures Friday morning destroyed the flowers on my apple trees, purple-leafed plum, and purple-leafed sand cherry.

What’s blooming in the area: Apples, crab apples, forsythia, daffodils, tulips. Leaves emerging on silver lace vine.

Ditches flowing.

Beyond the walls and fences: Siberian elm, alfilerillo, western stickseed, purple mat flower, common and native dandelions.

In my yard: Sand cherry still fragrant. Buds on Bath pinks, lilacs, vinca. Leaves emerging on apricot, snowball, forsythia, and weigela. Blue flax, sea lavender, catmints, Saint John’s wort, baptisia, Shasta daisy and Maximilian sunflower breaking ground.

What’s blooming inside: Zonal geraniums, petunia.

Animal sightings: Rabbit, bees on sand cherries, small brown birds, harvester and smaller ants, first grasshopper of the season.

Weekly update: A year ago, the sand verbena were getting ready to bloom. By July, the heat and drought had returned. The grasses hadn’t revived. There was no way I would have known this area had so recently bloomed.

A month ago I was walking along the side of the verbena hill, when I thought there was more gravel on the path than I remembered.

That was the first time I realized the wind was as important as the frost in exposing what lay beneath the surface.

Intellectually, I knew the ground where I was walking was a layer cake that alternated tiers of sand with ones of pebbles washed down from the Peñasco embayment. I could see the strata in the arroyo a few feet away.

I also knew from Wikipedia the taproots of Abronia fragrans could reach down anywhere from 7" to 3'. The surrounding grasses tend to concentrate their root mass in the top 6" of soil. Although needle grass roots may reach deeper, the ones in my yard are shallow.

I simply never connected the details. Someone, I kept my midwestern image that vegetation was a thatch more dependent on the topsoil than on what lay beneath.

It did not occur to me that maybe the reason that area was more fertile than the one ten feet away was that it had more gravel at the right level to retain water for the roots of the verbena, and, perhaps not enough to support the grasses in arid times.

1. Sand verbena blooming on the prairie last spring, 9 May 2012.

2. Santo Domingo basin with white clouds hanging low against the surrounding hills and a line of light colored dust at the horizon.

3. Same sand verbena growing area last summer, 19 July 2013.

4. Path near the sand verbena growing area a month ago, 29 March 2013.

5. Arroyo walls a bit upstream from the sand verbena area, 27 January 2013.

6. Thatch of grass growing on lava on La Bajada hill top last week, 15 April 2013.

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