ROSE FAMILY 221 



zontal floors of gravelly plains where perfection of drainage gives it a secure foothold. It is, 

 hovpever, absent from broad areas of barren hUls in the Coast Eanges, perhaps by excess of soil 

 vrater at critical periods or by lack of drainage. In the Sierra Nevada foothills it occurs at many 

 stations and often in a characteristic pure formation as on the East Fork Kaweah Eiver. There 

 are, however, broad gaps in its distribution in the Sierra Nevada foothills, where it appears either 

 infrequent, localized or absent such as : between Fresno Eiver and the North Fork Kings Eiver, 

 where it is replaced by Eriodictyon calif ornicum Greene ; Shasta Co. to Eldorado Co. It has not 

 been recorded from the Tehachapi Mts. 



Chamise is commonly gregarious and often forms a distinct chamisal belt between the chap- 

 arral belt of the low foothills and the Western Yellow Pine belt above. The purest and most 

 extensive formations are often those occurring on the steepest and driest south and west slopes. 

 Such marked belts occur frequently on the westerly slope of the sierran axis in Southern Cali- 

 fornia and are a part of the dramatic vegetation content of the country in the Kaweah Eiver 

 region of the southern Sierra Nevada and in the Greasewood Hills region, in western Tehama Co., 

 inner North Coast Eange. Yet again, as a further example : the east slope of the inner range of 

 the Santa Lucia Mts. from Salinas south to the Arroyo Seco, is striped by a narrow Chamise band. 

 This band occupies both of the local slopes of the narrow deep caiions, or if the right hand slope 

 lies directly north the Chamise band is replaced by chaparral. As the band runs southward it 

 becomes broader and more uniform on both local slopes, or if the slope have a swale or flat in it 

 low oak or chaparral replaces Chamise. Such extensive pure colonies are known as chamisal. 

 In cismontane California the geographic name Black Hills has its origin in pure formations of 

 Adenostoma fasciculatum, likewise the name Greasewood Hills. On the other hand this species 

 also occurs very commonly as scattered individuals through the hard chaparral as an associate of 

 Ceanothus cuneatus, C. leucodermis, Arctostaphylos manzanita, A. viscida, A. mariposa and many 

 other f rutescent species. It has a Avider ranger and is more abundant in individuals than any other 

 shrub species in California save only Ehus diversiloba T. & G. None other of our shrubs of wide 

 range, however, equals it in constancy of character. 



The individual is well-protected against completely destructive effects of chaparral fires by 

 its strong taproot which descends vertically to a depth of 3 to 8 feet or more wherever the subsoil 

 conditions permit. Strong lateral roots are also developed. After fire the plant regenerates by 

 shoots from the root-crown. Under repeated fires the root-crown increases in size and usually 

 becomes an enlarged woody structure 2 to 6 inches in diameter. A strong taproot is first estab- 

 lished by the seedling. After about 6 or 8 years (cf. fig. 168) a thickening occurs at base of the 

 stem a little below but mostly above the surface of the ground which becomes turnip- or bulb- 

 shaped, higher than broad, but sometimes globose. As the years pass extra shoots arise from 

 this bulb and the bulb-shaped base is eventually replaced by a more or less irregular and heavy 

 bulbous structure or root-crown. The younger plants with bulb-like bases seldom survive heavy 

 fires, but the older shrubs in the main offer effective resistance. After the Mt. Tamalpais fire of 

 1913, Adenostoma fasciculatum made crown-sprouts at a time when some other markedly virile 

 species, such as Arctostaphylos glandulosa Eastw. and Quercus wislizenii var. frutescens Engelm., 

 failed to do so. It seems probable that mature Chamise is rarely or never completely killed even 

 by repetition of running chaparral fires recurring at short intervals. 



Locs. — Coast Eanges: Blue Eock ridge, nw. Mendocino Co., Jepson; Comptche, Mendocino 

 Co., H. A. Walker 390; Houghs Sprs., ne. Lake Co., Jepson; betw. Adams Sprs. and Glenbrook, 

 Lake Co., Jepson; Howell Mt., Napa Eange, Jepson 6584; Vaca Mts., Jepson 13,832; Inverness, 

 Marin Co., Jepson; Eattlesnake Camp, Mt. Tamalpais, A. L. Grant; Moraga Eidge, Contra Costa 

 Co., Jepson; Mt. Diablo, Jepson; Saratoga, Santa Cruz Mts., Jepson 5632; Del Monte, Monterey 

 Co., Jepson 9760; Big Sur Eiver, Jepson; San Antonio trail, Santa Lucia Mts., Jepson; Waltham 

 Creek, sw. Fresno Co., Jepson. Sacramento Valley: College City, Alice King. Sierra Nevada 

 foothills: North Fork American Eiver, s. of Applegate, Placer Co., ace. L. S. Smith; Forest Hill 

 divide. Placer Co., L. S. Smith; Buena Vista, Amador Co., Jepson 9967; Gwin Mine, Calaveras 

 Co., Jepson; Parrots Ferry, Stanislaus Eiver, Jepson; North Fork Kaweah Eiver, Jepson; Mid- 

 dle Tule Eiver, Purpus 5581. S. Cal.: Liebre Mts., Munz 7056a; Santa Inez Mts., Jepson; Santa 

 Cruz Isl., Jepson 12,092 ; Ojai Valley, Olive Thacher; Mt. Wilson, Peirson 78 ; San Bernardino 

 foothills, Parish; Swain Canon, Santa Catalina Isl., Jepson; Cahuilla Valley, sw. Eiverside Co., 

 Jepson; Palomar Mt., Jepson; San Pasqual grade, San Diego Co., Jepson 8507; Santa Ysabel, 

 San Diego Co., Jepson. 



Var. obtusifolium Wats. Leaves blunt, 2 to 3 lines long, sessUe or very short-petioled. — 

 Western San Diego Co. Northern Lower California. The following with very short-petioled 

 leaves are intermediate toward the species: Santa Eosa Isl., T. Brandegee; San Diego, E. P. 

 Kelley; Howell Mt., Napa Co., Tracy 2230 (probably an independent mutant). 



Eefs.— Adenostoma fasciculatum H. & A. Bot. Beech. 139, t. 30 (1832), type loc. "sandy 

 plains. Bay of Monterey"; Jepson, Fl. W. Mid. Cal. 277 (1901), ed. 2, 205 (1911), Man. 503, fig. 

 500 (1925). A. fasciculatum var. densifolium Eastw. Bull. Torr. Club 32:199 (1905), type loc. 

 Mt. Wilson, near Pasadena, Fordyce Grinnell Jr. A. calif ornicum Gandg. Bull. Soc. Bot. France 

 59 :707 (1912), type loc. San Bernardino, Parish 4838. Var. oBTUSiromuM Wats. Bot. Cal. 1 :184 



