Origin and Habitat: Occurs in restricted and localized populations from fewer than a dozen disjunct sites in a six-square-mile area in the interior foothills in Central San Diego County and on land across the border in Baja California. Only about 9.000 individual plants are known to exist in habitat.
Altitude: 200 a 700 m.
Type locality: Near El Cajon.
Habitat: Grows in dry chaparral-covered slopes on clay soils derived from gabbro or metavolcanic bedrock and on stony, fine, sandy loams. The species is fire-dependent, flowering profusely after wildfires.
Synonyms:
Common Names include:
ENGLISH: Burried Nolina, San Diego Nolina, Nohna Interrata, Dehesa Beargrass, Dehesa Nolina
Description: It is a large yucca-like perennial succulent subshrub with narrow leaves similar to that of Nolina parryi but apparently no woody stem beneath the leaf clusters, this being buried underground and the clustered leaves borne at ground level. Mature plants are often 2-3 m across. It is one of 30 or so members of the genus Nolina.
Stem (rhizomatous caudex): Mostly below ground up to 2-3 meter long, horizontal or ascending, branched and producing a platform of rosettes .
Rosettes: 10-45 leafed
Leaves: 70-90(-150) cm long, 8-35 mm wide, thick and somewhat fleshy at the bases (base 2-7 cm wide), stiff, flat to somewhat concave above, waxy, attractive arching, very light glaucous green and minutely serrated along the edges.
Inflorescence: Erect 0,5-2 m tall, with tiny flowers arrayed along the branches, scape 5-16 mm wide at base, internodes 5-12 cm long with persistent bracts.
Flowers: Few millimetres long, light-coloured, with six whitish tepals about 3 mm long puberulent at the swollen tips. N. interrata has separate male and female plants, identical except when in flower.
Blooming season: June - July.
Fruit: Papery capsule about 12-15 mm wide with 3 chambers.
Seed: Roundish 4 x 5 mm wide, yellowish, tannish yellow or red brown, wrinkled.
Cultivation and Propagation: It is a resistant plant that tolerates poor soil and drought, but requires excellent drainage and usually does not give many problems in cultivation. It is not particularly fussy about moisture, though careful drainage is always a plus. It likes regular irrigation at time of growth. Outdoors it needs no irrigation once established.
Frost Tolerance: They cannot resist cold. In areas that receive frost or snow the species is best kept indoors or in heated glasshouses.
Maintenance: Removal of old dried basal leaves. During the winter months it may become dormant, during which little moisture is required, and the plants should be grown cool.
Propagation: Suckers, micropropagation or seeds.
