About Echinocereus pacificus (Engelm.) Britton & Rose
Echinocereus pacificus (Engelm.) Britton & Rose can grow solitary or form clumps. Clumps are 30–60 cm (12–24 in) across and typically contain around 100 stems. Stems are cylindrical to elongated, measuring 5 to 6 cm (2.0 to 2.4 in) long, and feature 10 to 12 ribs. Each stem has 4 to 5 strong, upright central spines that are white or light gray with darker tips, reaching 25 mm (0.98 in) in length. There are also 10 to 12 spreading, straight whitish or grayish radial spines, which measure 5 to 10 mm (0.20 to 0.39 in) long. The cup-shaped flowers are deep red-orange, 2.5 to 4 cm (0.98 to 1.57 in) in diameter, and emerge from the upper half of the stems. The fruits are spherical, fleshy, spiny, and 1.2 to 1.6 cm (0.047 to 0.063 in) long. The chromosome count for this species is 4n=44.
This cactus is distributed on granite slopes and in xeric scrub in Baja California, Mexico, growing at elevations between approximately 110 and 2600 meters. It is found growing alongside Adenostoma fasciculatum, Stipa speciosa, Arctostaphylos peninsularis, Dudleya pulverulenta, Lotus rigidus, Nolina microcarpa, Pinus monophylla, Rhamnus crocea, Opuntia phaeacantha, Cylindropuntia acanthocarpa, Pinus quadrifolia, Ferocactus viridescens, and Malosma laurina.
