blue hesper palm
Stems: Solitary, erect, to 15 m in height and 45 cm in diameter and somewhat swollen at the base. Old leaves or leaf bases may cover the stem, but with age, it becomes bare with rings of leaf scars. Leaves: Costapalmate, induplicate, icy-blue or blue-green, up to 2.5 m across, and divided to about the midpoint into stiff segments with bifid tips. The petioles are armed with robust marginal teeth and covered with wooly hairs. Flowers and fruit: The spectacular inflorescences are up to 5 m long and hang downward from among the leaves. Flowers are hermaphroditic, with yellow petals. Fruit oblong to spherical, about 2 cm across, and brown to black when mature.
Field: A robust, solitary palm with slight swelling at the base of the stem, icy-blue to blue-green leaves, and irregular teeth along the petiole margins
Lab: Black to brown floccose indumentum
Washingtonia sp. are somewhat similar and grow in many of the same locations, but Washingtonia palms are grassy green, not blue or silvery. Brahea brandegeei could be confused with B. armata, but its leaves are green on the upper surface.
Native to sandy or rocky soils in desert of northwestern Mexico
Often planted in California and other hot, dry regions of the southwestern United States
Brahea armata S.Watson
Arecaceae/Palmae
Brahea clara (L.H.Bailey) Espejo & López-Ferrari
Brahea roezlii Linden
Erythea armata (S.Watson) Watson
Erythea clara L.H.Bailey
Erythea elegans Franceschi ex Becc.
Erythea roezlii (Linden) L.H.Bailey
Glaucothea armata (S.Watson) O.F.Cook
Glaucothea elegans (Franceschi ex Becc.) Johnston