This section is from the book "The Standard Cyclopedia Of Horticulture Vol2", by L. H. Bailey. See also: Western Garden Book: More than 8,000 Plants - The Right Plants for Your Climate - Tips from Western Garden Experts.
9. alpinum, Linn. Height 12 ft., bluish above, from a thick root: radical leaves deeply cordate-triangular, acuminate, coarsely double-crenate; stem - leaves round-cordate, often 3-lobed at the apex or palmatifid: head globose-cylindrical, about 1 in. long; involucral bracts 12-18, lance-oblong, rigid, multifid; fls,, many; sepals ovate-lanceolate; petals somewhat rectangular. Eu. B.M. 922. G.C. III. 53:139. G.M. 46:136. Gn.W. 21:278. G.W. 3:576; 15, p. 478. R.H. 1876, p. 113. Gn. 46:523. - There is a white variety. Prized for the attractive blue color of the heads and upper part of the plant.
10. Oliverianum, Delar. (E. alpinum variety Oliver-ianum, Spreng.). Hybrid, perhaps of E. planum and E. giganteum, or perhaps with E. alpinum: plant strong,
3 ft.: lower leaves long-petioled, broadly cordate-ovate, indistinctly 3-lobed at the apex, unequally spinulose-serrate; younger and the lower cauline leaves 3-lobed or -parted and the lobes again more or less lobed or angled and the margins spinose-serrate: head blue, cylindrical-ovoid, or ovate, many-flowered; involucral bracts 10-15, subulate or linear, somewhat spinulose. Gn. 45, p. 223; 60, p. 425. Gn. W. 20:791. G.W. 15, p. 497.
11. tripartitum, Desf. Probably a hybrid: radical leaves unequally spinulose-serrate with a large obtuse middle lobe; stem - leaves deeply 3-parted, the lobes lanceolate and rigid, spiny-toothed: head globular, small; involucral bracts 6-9, narrow-lanceolate, spiny margined.
12. giganteum, Bieb. (E. asperifolium, Delar. E. glaucum, Hoffm ). Stout, 6 ft., the root thick and turnip-shaped, the stem simple below and 4-5-forked above: leaves coriaceous, the basal ones broadly cordate or cordate-triangular, toothed; stem - leaves more or less 3-lobed, spinulose-dentate: heads cylindrical or ovoid-cylindrical, 3-4 in. long, in an ample infloresence, blue or pale green; involucral bracts lanceolate to obovate, very rigid, much cut; flowers very many; sepals ovate or ovate-lanceolate; petals obovate-lanceolate. Caucasus, Asia Minor. Gn. 46, p. 523; 70, p. 111. G. 34:95. R.H. 1906, p. 379. G.W. 15, p. 479.
13. planum, Linn. (E. planifblium, Pall. E. lati-fdlium, Gilib. E. intermedium, Weinm.). Root thick turnip-shaped, very long: stem 3 ft., mostly single, 3-5-forked at top: basal leaves cordate, oblong or oval or broadly obovate, obtuse, spinulose, usually palmately 7-9-nerved; lower stem - leaves short-petioled, shaped like the basal leaves or 3-lobed, the lobes deeply serrate or cut, the upper ones sessile and 3-5-parted: heads blue, ovoid or nearly globular, about 1/2in. long; involucral bracts mostly linear, rigid, somewhat spinulose-serrate; sepals lanceolate; petals ovate-oblong. Eu., Asia. G.L. 18:136. - A variety roseum is offered.
14. dich6tomum, Desf. (E. tricuspidatum, Tenore). Two ft. or less, glaucous-blue, the stem strong, few-lvd., branchy, 3-5-forked at top: lower leaves long-petioled, cordate-oblong or obovate, very obtuse, serrate or crenate, reticulated; upper leaves rigid, 5-parted: head nearly globose or ovoid-globose, about 1/2in. long; involucral bracts 6-7, rigid, narrow-linear or subulate, somewhat spinulose, pungent-pointed; sepals ovate or ovate-lanceolate, spine-tipped; petals ovate-oblong. Medit. region.
15. cceruleum, Bieb. About 3 ft., blue, the root thick and long turnip-shaped, the stem usually solitary, 4-5-forked above, the branches long: basal leaves all long-petioled, cordate, cordate-ovate or cordate-oblong, crenate-serrate, outer ones undivided, inner ones 3-lobed: heads small; involucral bracts 4-6, rigid and wide-spreading, linear-lanceolate, spinulose; sepals narrow-lanceolate; petals oblong. Caucasus and E.
16. Leavenworthii, Torr. & Gray. Purple-violet above, 3 ft., the stem strict and full-lvd., at the top 3-forked: basal leaves oblanceolate and mostly obtuse, spinose-dentate, the others deeply palmate-parted, the divisions cut-pinnatifid and the segments spreading and pungent-pointed: heads ovoid-cylindrical, 2 in. or less long; involucral bracts 7-9, linear-lanceolate, spinose-pinnatifid; sepals pinnatifid. Dry soil, Kans. to Texas.
cc. Basal leaves on the flowering plant all lobed or divided.
17. serbicum, Pane. Height 1-1 1/2 ft., blue above: root elongated, thick, somewhat woody: stem slender, sparsely lvd., short-branching and 3-4-forked above: basal leaves long-petioled, fresh green, divided into 5-7 grass-like segments; stem - leaves more or less clasping or short-petioled, the segments very narrow and remotely spinulose-cut: heads small, globose-ovoid; involucral bracts 5-7, rigid, narrow-linear, sharp-pointed; sepals broad-ovate, obtuse; petals broadly oblong-ovate. Servia.
18. Spinalba, Vill. Plant rigid, whitish green, more or less blue above: stem stout, at the top 3-4-forked: leaves coriaceous, rigid, broadly cordate-ovate, palmately 4-5-parted, the margins undulate and spiny-toothed: head blue, o void-cylindrical; involucral bracts about 10 and very rigid, deeply pinnatifid, spine-pointed; sepals lanceolate or more or less ovate; petals oblong-linear. Eu., in the Alps.
19. Bourgatii, Gouan (E. Tournefbrtii, Bub.). Low, usually about 1 1/2 ft.: root thick, somewhat turnip-form: stem mostly solitary, simple below, sparingly branched above, apex 3-forked: leaves somewhat coriaceous, pale green, rigid, nearly orbicular or somewhat reniform, palmately 3-5-parted and again lobed, spiny-toothed; stem - leaves palmate, somewhat clasping: heads blue or rarely green, nearly globose or ovoid-globose; involucral bracts 9-15, spiny or not; sepals lanceolate, acute; petals spatulate. Medit. region.
20. Zabelii, Hort. (E. alpinum x E. Bourgatii). Plant rather robust, 1 1/2 ft.: basal leaves suborbicular, 3-parted; the segments cuneate at base and deeply 3-lobed and again 3-lobed, margins strongly spinulose-serrate: head globose-cylindrical, 1 in. or more long; involucral bracts, 12-14, rigid, lanceolate, spinulose-dentate, blue or amethystine. G.W. 15, p. 496.
21. amethystinum, Linn. (E. pallescente, Mill.). Fig. 1417. Stout, 1 1/2 ft. and more, blue or amethystine above or sometimes whitish: root thick, long-cylindrical: stem remotely leafy, branched, 4-5-forked at top: leaves rigid, obovate or oblong-ovate, bipinnatifid, spinose-dentate; upper stem - leaves clasping, pinnately parted, spinulose-dentate: heads ovoid-globose, 1/2in.. or more long, the peduncle thick and sulcate; involucral bracts 6-9, unequal, linear-subulate or lanceolate, sharp-pointed; sepals ovate-lanceolate; petals ovate-oblong or nearly rectangular. Eu. Gn. 46, p. 522; 55, p. 454. G.L. 23:199. Variable. variety multifidum, Wolff (E. multifidum, Smith) has much-cut leaves
Any number of eryngiums may be expected to appear in the list, as they are likely to strike the attention of collectors. They appear to hybridize rather freely. E. hybridum is a trade name for garden forms, but it has no botanical standing. - E. Rothenbergii is a garden hybrid of E. alpinum and E. giganteum. - E. azureum and E. caelestmum are garden names without botanical standing; the latter is said to be E. amethystinum. - E. Ebeneum=E. ebur-neum(?). - E. Wrightii is said to be a free form of E. planum, bloom-ing for a long period. L H B