696 



CEANOTHUS 



CEANOTHUS 



A. Lvs. alternate. (Nos. 1-13.) 



B. Margin of Ivs. serrate or crenate. 



c. Foliage glabrous beneath or slightly pubescent. 



D. Fls. white: Ivs. thin, deciduous. 

 E. Peduncles slender, at the end of the new growth. 

 1. americanus, Linn. Fig. 847. Low, erect shrub, to 

 3 ft.: Ivs. ovate, usually acute, finely and irregularly 

 serrate, bright green and dull above, paler and pubes- 

 cent or nearly glabrous 

 beneath, 1^-3 in. 

 long: fls. in terminal 

 and axillary panicles 

 on slender peduncles, 

 forming large, corym- 

 bose panicles. July- 

 Sept. From Canada 

 to S. C. and Texas. 

 B.M. 1479. Gt. 61, p. 

 92. Gn. 56, p. 137. 

 Common in dry woods 

 and making a pro- 

 fusion of bloom, which, 

 however, is short-lived. 

 * Many hybrids have 

 been raised from this 

 , species in Eu. (see C. 

 ' hybridus). Var. inter- 

 medius, Trel. (C. in- 

 termedius, Pursh), has 

 smaller, ovate or 

 ovate - lanceolate Ivs. 

 and the fls. in small, 

 very slender - pedun- 

 cled, short racemes or 

 panicles. Tenn. to S. C. 

 2. ovatus, Desf. (C. 

 ovdlis, Bigel.). Low 

 shrub: Ivs. elliptic to 

 elliptic-lanceolate, ob- 

 tuse or acute, crenulate-serrate, nearly glabrous, glossy 

 above, 1-2 in. long: infl. like the former, but usually 

 smaller. New England to Colo, and Ala. 



EE. Peduncles usually stout, from lateral buds of the 

 old wood. 



3. sanguineus, Pursh (C. oregdnus, Nutt.). Tall 

 shrub, with purple or reddish glabrous branches: Ivs. 

 orbicular to ovate or obovate, obtuse, serrate, nearly 

 glabrous, 1-3 in. long: fls. in rather long, narrow pani- 

 cles, on stout, leafless peduncles, axillary, from branches 

 of the previous year. May, June. Brit. Col. to Calif. 

 B.M. 5177. 



DD. Fls. blue or pink, rarely white: Ivs. usually 

 half-evergreen. 



4. hybridus, Hort. Hybrids of garden origin, chiefly 

 between C. americanus and C. thyrsiflorus, between C. 

 ovatus and C. thyrsiflorus and between C. americanus 

 and C. azureus; the hybrids of the first group may be 

 classed under C. roseus, Koehne, of the second under C. 

 pallidus, Lindl., and those of the third group under C. 

 Arnouldii, Hort. Some of the most distinct are: dlbo- 

 plenus, with double white fls.; atrocaeruleus purpiireus, 

 fl. blue, foliage purple when young; Arnouldii, fls. sky- 

 blue, in large panicles; Gloire de Versailles, with 

 bright blue, large panicles (M.D.G. 1903:485); Gloire 

 de Plantieres, fls. dark blue, in large panicles; Victor 

 Jouin, fls. deep blue, darker than in the preceding, one 

 of the hardiest hybrids; Ciel de Provence, fls. deep blue, 

 profusely produced (R.H. 1903:332); Marie Simon, 

 fls. flesh-colored; roseus, fls. pink (R.H. 1875:30); 

 pallidus, fls. pale blue, Ivs. green and pubescent below 

 (B.R. 26:20). 



5. thyrsiflorus, -Each. Shrub or small tree: Ivs. ob- 

 long, obtuse, crenate-serrate, nearly glabrous, 1-1 J^ 



847. Ceanothus americanus. ( X Ja) 



in. long: fls. blue, rarely white, in narrow panicles, 

 about 3 in. long. May-July. Ore. to Calif. B.R. 

 30:38. S.S. 2:64. G.C. III. 20:363; 37:179; 41:221. 

 Gn. 74, p. 303. G.M. 50:430. A very fine, free-flower- 

 ing species of beautiful blue color. Probably natural 

 hybrids of this species are: C. Veitchidnus, Hook. (C. 

 thyrsiflorus x C. rigidus), with deep blue fls. in dense 

 panicled clusters (B.M. 5127; F.S. 13:1383), and C. 

 Lobbianus, Hook. (C. thyrsiflorus x C. dentatus), with 

 deep blue fls., in oval, peduncled, solitary clusters. B. 

 M. 4810 (4811 by error). F.S. 10:1016. 



cc. Foliage tomentose or densely pubescent beneath: half- 

 evergreen or evergreen (see also C. hybridus). 

 D. Branchlets and the veins beneath nearly glabrous: Ivs. 

 very obtuse: fls. white. 



6. velutinus, Douglas. Tall shrub: Ivs. persistent, 

 broadly elliptic, mostly subcordate, obtuse, serrate, 

 dark green and glabrous above, canescent beneath, but 

 the veins glabrescent, 2-3 in. long: fls. in large, com- 

 pound panicles at the ends of the branches. June, July. 

 Brit. Col. to Colo, and Calif. B.M. 5165. 



DD. Branchlets and the veins tomentose or pubescent: Ivs. 



mostly acute: fls. usually blue. 



E. The Ivs. glabrous or puberulous above, whitish or 

 tawny tomentose beneath. 



7. arbdreus, Greene (C. velutinus var. arbdreus, 

 Sarg.). Small tree, with whitish bark: branchlets at 

 first angled and pubescent, later glabrescent and glossy : 

 Ivs. elliptic-ovate, obtusish or acutish, rounded or sub- 

 cordate at the base, closely serrate, with close white 

 tomentum beneath, 1^-3 in. long: fls. pale blue to white 

 in panicles 2-3 in. long. Spring. Isls. off the Calif, 

 coast. S.S. 2:65. 



8. azureus, Desf. (C. bicolor, HBK. C. cseriileus, 

 Lag.). Tall shrub: branchlets terete, densely tomen- 

 tose: Ivs. oblong-ovate or oblong, acute or obtuse, 

 rounded at base, serrate, with villous tawny tomentum 

 beneath, 1-3 in. long: fls. deep blue, in slender panicles 

 2-4in. long. Spring. Mex. L.B.C. 2:110. B.R. 4:291. 

 P.M. 2:74. Gn. 61, p. 223. Under this name, a hybrid 

 species with C. americanus is often cult. 



EE. The Ivs. villous or hirsute on both sides, usually green 

 beneath. 



9. hirsutus, Nutt. Shrub or small tree, with villous 

 branches: Ivs. broadly elliptic or ovate, rounded or 

 cordate at the base, obtuse or acute, with glandular 

 teeth, 3^-2 in. long: fls. deep blue to purplish, in nar- 

 row panicles 1-2 in. long. April, May. Calif. Called 

 "wild lilac" in Calif. Var. Orcuttii, Trel. (C. Orcuttii, 

 Torr.). Fls. blue, paler: fr. loosely villous. 



BB. Margin of Ivs. entire or nearly so (sometimes serrate 



on vigorous shoots). 

 c. Shrub prostrate: fls. white. 



10. Fendleri, Gray. Low, prostrate and spiny shrub : 

 Ivs. oval, rounded or nearly acute at both ends, entire, 

 rarely finely serrulate, grayish green, minutely tomen- 

 tose beneath, J^-l in. long: fls. white, in short racemes, 

 terminal, on short, lateral branchlets. June, July. 

 From S. D. to New Mex. and Ariz. R.H. 1901, p. 423. 

 M.D.G. 1908:208; 1912:499. A very graceful and 

 free-flowering shrub of almost creeping habit, well 

 adapted for covering dry, sandy banks; half evergreen 

 and hardy N. 



cc. Shrubs tall, upright. 

 D. Branchlets terete or slightly angled, rarely spiny. 



11. integerrimus, Hook. & Arn. Tall, erect shrub, 

 with glabrescent branches: Ivs. broadly elliptic or ovate, 

 obtuse, sparingly hairy or glabrous; bright green be- 

 neath, 1-3 in. long: fls. blue, sometimes white, fragrant, 

 in 3-6 in. long, narrow panicles. April-June. Wash, to 

 Calif, and S. E. Ariz. B.M. 7640. 



