Screwbean
Prosopis pubescens
Photographed near the Salt River at Phoenix, Arizona, USA. This image is hosted at Wikipedia
Screwbean Mesquite, Prosopis pubescens. The double-thorned insect at far right is Platycentrus acuticornis.
FRUIT: Legumes appear by mid-summer and are twisted around and around
giving the appearance of a screw, thus the namesake for the plant.
TREE: A small or medium sized tree with short spines and brown bark.
LEAVES: Light green leaves are twice-compound, i.e. the rachis splits
once into two or four (occas. 6) secondary rachises upon which the ultimate leaflets appear.
RANGE: Sonoran and Chihuahuan Deserts most commonly along flood-prone
rivers where the soil may be seasonally saline or damp. It is often planted
near wastewater treatment facilities.
FLOWERS: Spikes of numerous, small yellow flowers. The petals are minute
whereas the stamens are elongate and conspicuous
ARMED: Spines are 1 to 3 cm short and are white at maturity.