White Thorn Acacia

Bina lowered her head. The blisters on her feet ached and she guided her finger across the bubbles of skin. Her stomach growled. She followed the run-off contours of the dry arroyo with her eyes down the bare banks and across the browns of the desert into the setting sun. Clusters of red-green bean pods dangled from the limbs of the white thorn acacia that shaded her. She looked up. Food she thought. Good food.

Acacia Constricta also known as White Thorn Acacia or Mescat Acacia is a native plant in the Trans-Pecos region of Texas. The red-maroon barked shrub tree can grow to heights of 15 feet and to keep grazers at bay, grows one to two inch white thorns from its gray colored branches. Often when there is no grazing or pruning the plant will not grow thorns as it is expensive in materials for the plant to manufacture.

The Acacia is part of the legume family and thus a nitrogen fixer. Legume family root nodules host bacterias known as diazatrophs that convert nitrogen in the air (N2) into ammonia (NH3) which is secreted into the soil and used by plants to biosynthesize nucleotide for DNA and amino acids for proteins. Farmers often plant legumes like soybeans and alfalfa as one of their rotational crops to recharge their field soil.

The bi-pinnate compound leaves of the white thorn acacia fall in drought and occasionally in winter. The plant usually flowers in spring and again in late summer after the monsoon season. It produces a bright yellow fluff ball as its flower and clusters of green-red seed pods with high protein beans contained in a sweet fibrous seed sheath. Oddly though, the plant produces little nectar or pollen and thus has few visiting insects.