80 HANDBOOK 14 8. U.S. DEPARTMENT OF AGRICULTURE 



surpassed by leaves, in flattish- to roundish- 

 topped (cymose) end clusters, blooming 

 July-Oct. ; ray flowers lacking; disk flowers 

 mostly 5 ; seed heads (at least some) persistent 

 until flower buds of following season appear; 

 "seeds" 5-angled, less than % inch long, 

 hairy; leaves 1-, 3-, and/or 5-nerved, often 

 sticky -resinous and spirally twisted; twigs 

 with white or pale green bark; mostly bushy 

 shrubs branched from near base; taproots 

 dividing near soil surface; characters variable, 

 sometimes intergrading in the following 

 varieties (or subspecies) of 



Douglas rabbitbrush 

 (Chrysothamnus viscidiflorus) . 

 46. Twigs, leaves finely, more or less densely 

 hairy, especially near the usually small, 

 compact flower-head clusters; low shrubs, 

 rarely more than 2 feet high. 

 47. Leaves pale grayish-green, narrow, to 

 Yu inch wide. 

 48. Leaves to nearly 2 inches long and 

 1/25 inch wide, mostly 1 -nerved, often 

 twisted; shrubs to 20 inches high; 

 disturbed areas or on poor soils, with 

 sagebrush; rather common, e. Oreg., 

 e. Wash. 



downy rabbitbrush (Chrysothamnus 

 viscidiflorus puberulus). 

 48. Leaves to I inch long, l/i2inch wide, 

 sometimes 3-nerved and slightly twist- 

 ed; to 1 foot high; dry plains, central, 

 s. Oreg.; type locality, plains of 

 Truckee River, Nevada Co., Calif. 



Truckee (or low) rabbitbrush 

 (Chrysothamnus viscidiflorus 



humilis). 

 47. Leaves bright green, lance-shaped, to 

 2 inches long, l / 4 inch wide, mostly 3- 

 and/or 5-nerved, seldom twisted, abrupt- 

 ly pointed at tips; stems stiffly erect, 

 to more than 2 feet high, e. Oreg., e. 

 Wash. 



lanceleaf rabbitbrush 

 (Chrysothamnus viscidiflorus 



lanceolatus). 

 46. Twigs, leaves mostly hairless except for 

 fine, stiff marginal hairs, often sticky- 

 resinous. 

 49. Shrubs tall, to 4 feet or more high; 

 leaves bright or bluish green, to }i inch 

 wide, often 3-nerved, sometimes spirall}" 

 twisted ; flower-head clusters open, broacl, 

 often sticky-resinous; flower-head bracts 



