Plant Highlights
Plant Highlights By Date Plant Highlights Alphabetically
Plant Highlight: Nolina nelsonii
by Brian Kemble
About the family placement
The genus Nolina contains about 30 species, some of them stemless and grass-like in appearance, and others developing thick trunks over time. While they were formerly placed in the small family Nolinaceae, this family has now been folded into the Asparagaceae, as the subfamily Nolinoideae*. Like the other plants in the Nolinoideae, the Nolina species have separate male and female individuals, though it is not possible to tell which sex a plant is until it flowers.
Area of Occurrence
The genus occurs in the southern U.S., from California to Florida, and southward to Oaxaca in southern Mexico. Many of the species have very localized distributions, and this is true of Nolina nelsonii, which comes from northeastern Mexico. It occurs only in the Sierra Madre Oriental in southwestern Tamaulipas, at altitudes of about 4,000 to 8,000 ft. (1,200 to 2,500 m). The habitat is open semi-desert scrub vegetation, with agaves, dasylirions and Brahea decumbens growing in the vicinity. The taller-growing green-leaved Nolina hibernica occurs nearby, but at higher elevations in pine forest habitat.
About the plant
Nolina nelsonii is a trunk-forming species, attaining a height of up to nearly 15 feet (4.5 m). Plants may be single-headed, but often they divide at the growing point to make a multi-headed crown, though not with a large number of heads. Our multi-headed specimen at the Ruth Bancroft Garden has heads about 5 feet in diameter (1.5 m), with the whole crown being about 10 feet across in its longest axis (3 m). The stiffly radiating leaves are about 20 to 28 inches long (.5 to .7 m) and 1.2 to 1.6 inches wide (3 to 4 cm), tapering gradually toward the tip. The leaves are pliable rather than rigid, and on some specimens, they may curve downward. The leaf color is pale blue or blue-green, earning this species the common name of Blue Beargrass Tree (beargrass is a common name for various species in the genus, but it is also often used for Xerophyllum tenax, in a different plant family). While not conspicuously toothed, the leaf margins are minutely serrated and can cause paper cuts. Old leaves swivel downward and are pressed against the trunk; only rarely on older specimens can the woody brown trunk be seen.
Male plant
Male plant
Female plant
About the flowers
This is a spring-flowering species, with the first flowers opening in May at the Ruth Bancroft Garden. The whole inflorescence is about 6½ to 10 feet long (2 to 3 m), with a width of about ⅓ this. The stout peduncle supports a branched and re-branched panicle, bearing many thousands of small white or whitish flowers. The female inflorescences have a slight greenish-yellow tinge, while the male ones are more of a creamy yellowish-tan. The tiny individual flowers are about .12 to .15 inch across (3 -4 mm). The female ones are cupped and tinged greenish, while on the male ones the 6 white tepals are curled back to expose the 6 anthers bearing yellow pollen. As with other species in the family, the flowers are extremely attractive to bees. Female flowers develop into papery 3-winged capsules with a diameter averaging about a third of an inch (8 to 10 mm). Within are 3 chambers holding the round tan seeds, which have a diameter of about a tenth of an inch (2.5 mm).
Female Flower
Male flower
*In the 2020 edition of the Monocotyledons volume of the Illustrated Handbook of Succulent Plants, an alternative classification is used, with the plants in the former Nolinaceae being placed in the family Ruscaceae, along with Sansevieria and Dracaena.
