Blossoming from April to October, this species is common at elevations
between 1,000 and 3,000 feet Nevada to New Mexico, Arizona, California,
and northwestern Mexico. There are fifteen or more other species, many
of which are found in a desert habitat and range in size from
low-growing herbs to small shrubs 3-5 feet high. Senna is sometimes
called “rattlebox” because the nearly ripe seeds rattle in their woody
pods when the plant is stirred, startling the hiker who immediately
thinks “rattlesnake!” A closely related species, _leptocarpa_, is noted
for its foul-smelling foliage.
_Cassia covesii_ Pea Family
[Illustration: SENNA]