About Cupressus macnabiana A.Murray bis
Hesperocyparis macnabiana (scientific name Cupressus macnabiana A.Murray bis) is an evergreen shrub or small tree, 3–12 metres (9.8–39.4 ft) tall, rarely reaching 17 metres (56 ft). It has a spreading crown that is often broader than it is tall. Foliage grows in dense, short flat sprays, unlike most other California cypresses which do not have flattened sprays; it is bright glaucous gray-green with a strong spicy-resinous scent. Mature leaves are scale-like, 1–2 mm long with an acute apex, and have a conspicuous white resin gland at the leaf center. Young seedlings produce needle-like leaves up to 10 mm (0.4 inches) long during their first year. Seed cones are oblong-ovoid to cuboid, 15–25 mm long and 13–20 mm broad, with six (rarely four or eight) scales; each scale bears a prominent umbo. Seed cones are strongly serotinous, and do not open to release seeds until the parent tree is killed by wildfire. This allows heavy seed release to colonize bare, fire-cleared ground. Pollen cones are 3–4 mm long, and release pollen in the fall. Hesperocyparis macnabiana is endemic to northern California. It is one of the most widely distributed of all native California cypresses, growing in chaparral, oak woodlands, and coniferous woodlands habitats along the inner northern California Coast Ranges and the foothills of the northern Sierra Nevada. MacNab cypress is often associated with ultramafic soils.
