A N F Keys
1 Solitary, geophytic perennials, in certain years (following fire) forming a basal rosette of flexible, strap-shaped leaves lacking terminal spine; flowers opening before sunset and closing before dawn, thereafter having the perianth twisted over the superior ovary; perianth segments linear-oblanceolate, 15−26 × 2.5−3 mm, white, initially with or developing a colored midstripe; capsule spheroidal, 5−7 mm, 6-seeded .. Chlorogalum pomeridianum var. pomeridianum [pics]
1' Clonal, evergreen perennials, forming basal rosettes of succulent, stiff, spine-tipped leaves; flowers open for days; perianth segments at least 8 mm wide at base (upper portion sometimes inrolled and appearing linear); capsule oblong, > 20 mm long with stacks of many flat seeds
2 Blades 50−270 mm wide at midblade, conspicuously glaucous with loose surface wax, margins spinose; flowers erect, yellow and green, with perianth tube, containing copious nectar; stamens erect, exserted, with versatile anthers 28−37 mm long; ovary inferior .. Agave americana var. americana [pics]
2' Blades 10−29 mm wide at midblade, sometimes appearing glaucous but without loose surface wax, entire; flowers arching to pendent, cream-colored, with 6 tepals (no perianth tube), lacking nectar; stamens spreading, club-shaped, with basifixed anthers ca. 2 mm long; ovary superior .. Hesperoyucca whipplei [pics]
NB. The family designation of each genus has been highly disputed and is still unsettled. It is possible that these three genera should not be treated together within Agavaceae. Agavaceae may also be treated within Asparagaceae.
The text of the above keys used with permission from
A Naturalist's Flora of the Santa Monica Mountains and Simi Hills, California
© Copyright
Barry A. Prigge and Arthur C. Gibson
2013