Friday, February 21, 2014

Hackamore Acres

When our local grocery store was built six years ago, I was glad that I could now walk just a mile to do my shopping, but grieved a little for another patch of desert that was transformed into seventy-five acres of asphalt and concrete. Fortunately, the other half of this island surrounded by a moat of roadways between Hackamore and Happy Valley Road, still remains for me to wander and to study the natural and unnatural history there. From the air, the desert side shows a maze of trails created by wildlife and the occasional human passing through. The mall side appears to have nothing growing at all, but this is hardly true. 
This week I made a comparative floral inventory of the two parcels of land. Creosote bush is the dominant plant on the wild side, with a few mesquites, palo verde and wolfberry shrubs mingling in.   Patches of globe mallow (Spaeralcea ambigua) and African chamomile (Oncosiphon piluliferum) flourish wherever there is a little cover from deadfall or a dip in the landscape where soil and water accumulate.  Over forty other species of plants seek refuge in the shade of the larger shrubs. A few hardy annuals, especially plantain (Plantago ovata) and burrcomb (Pectocarya recurvata), colonize the wide expanses of otherwise bare earth.  Quail, ground squirrels, desert cottontail, white-crowned sparrows and lizards are some of the critters that make a living here too. 

Crossing the curbed boundary between the two sides of Hackamore Acres, the diversity of plants and animals that occupy the parking lot are entirely different. Well, obviously. Except for a few token creosotes and triangle leaf bursages, all of the forty-one species that have been selected to live in the sea of asphalt are not found in the wild desert next door. Landscapers do a thorough job of weeding out the few introduced species that have established on the desert side.  Even the birds are different. Over in the parking lot and on sidewalks, you're more likely to see house sparrows, pigeons and grackles. This is a distinctly urban ecology. But this is also a miracle! That anything can survive in this radically altered landscape is, in some ways, a testimony to the power and resilience of life.

I've come to appreciate both sides of Hackamore Acres. I admire the trees and shrubs that can survive (albeit with an IV of sorts, water and nutrients provided through a drip system) in the super-heated environment of the parking lot. Emu bush, rosemary, oleander and lantana are year-round sources of nectar, pollen, seeds and leaves for birds and insects to feed on. Willow acacia, if left untended for more than a few months, will sprout many seedlings. Surely they would form a forest in the future if we ceased pruning, weeding and hosing the gravel with herbicides.

I romanticize the wildness of creosote flats that smell so sweet after a rainstorm. Arizona poppies and spiderling that erupt from seemingly barren soils after a good monsoon rain remind me that no matter what abuses we torture the earth with, seeds blown in will restore the land in time. Life is patient.

Tuesday, February 11, 2014

Stone Buster

You gotta love a plant that was given the name Hairy Rupturewort (Herniaria hirsuta). With a name like that, you better be tough, and tough it is. This inconspicuous little plant lives in cracks, or ruptures, in the asphalt of our neighborhood streets, one of the hottest, driest environments a plant could take root in.  Peering at it through my hand lens, I saw that the leaves are covered with soft hairs. Although the cracks probably began due to the natural heaving of the earth, rupturewort and other plants that occupy this microhabitat help to widen the cracks. Oblivious, or at least unhindered, by the local traffic, rupturewort adds sinuous stripes of green to the road. The plant's natural habitat in northern Africa is probably in similar cracks in rocks.

Rupturewort was imported to North America as a horticultural marvel and herbal remedy. Another species, Herniaria glabra, or smooth rupturewort (i.e. not hairy), is marketed as a "carpet" plant to use in walkways, and as medicinal tea or extract. You can even purchase a poster that includes a botanical illustration of rupturewort.

Moroccan urologist, Fouad Atmani, has been experimenting with rupturewort to better understand its effects on kidney stones. His 2004 article, Effect of herb extract from Herniaria hirsuta on calcium oxalate crystallization in vitro; and another published in 2003, Effect of aqueous extract from Herniaria hirsuta on experimentally induced calcium oxalate nephrolithiasis in rats, document that the herb is indeed useful in dealing with kidney stones, although it does not actually rupture, or break them. What it does do is inhibit the stones from adhering to kidney tissue, which helps to reduce mineral build-up and the excruciating pain and other side effects that comes with it.  Extracts from the plant have been used for centuries as a medicinal remedy to treat kidney stones and as a diuretic. Now Dr. Atmani's research has shown that early herbalists seemed to know what they were doing.

Is it a divine synchronicity that my fascination with this plant coincided with my own personal episode of kidney stones? The world works in mysterious ways! Time to make some rupturewort tea. Fortunately, there is a plentiful supply in the street.