PLANTS DECIDUOUS • SPRING AND 



SUMMER 



Leaves Alternate and Compound 



1. Plants unarmed. 

 2. Leaves with 5 or more leaflets. 



3. Sap milky; leaflets 7-31, coarsely toothed, whitened (glau- 

 cous) on under surface, often rich in tannin; twigs stout, 

 large-pithy, somewhat 3-angled; flowers small, greenish; 

 "berries" (drupes) red, sticky-hairy, massed in conspicuous, 

 much-branched, pyramidal end clusters (panicles) ; shrubs 

 usually not much over 6 feet high, rarely treelike, often in 

 large patches connected underground by long-running root 

 branches, not poisonous; along roadsides, in canyons, e. Oreg., 



e. Wash smooth sumac (Rhus glabra) . 



3. Sap not milky. 



4. Leaflets 5-7 (rarely 3), silky-hairy on both sides, narrowly 

 oblong or linear; margins entire, somewhat rolled under; 

 stipules conspicuous, grown to leafstalk base, persistent 

 on twig after leaf falls, flowers yellow; "seeds" (achenes) 

 very hairy, small, many; stems twisted; bark shreddy, 

 brown; low, bushy shrubs; moist mountain valleys or 

 meadows, lower altitudes, e. Oreg., e. Wash. 



bush cinquefoil (Potentilla fruticosa) . 

 4. Leaflets 7-17, with dotlike glands (often also hairy) at 

 points of attachment to "midrib" (rachis) ; margins toothed, 

 at least toward leaflet tips; the fragrant white flowers and 

 the orange to red or scarlet "berries" (pomes) in flat- or 

 roundish-topped end clusters (compound corymb) ; stems 

 few-branched; bark smooth; shrubs tall, often growing in 

 clumps; moist mountain sites, e. Oreg., e. Wash. 



mountain-ashes (Sorbus spp.). 

 5. Leaflets 11 or more, lance- to oblong-lance-shaped, firm; 

 upper surface glossy, wrinkled, net-veined; margins finely, 

 singly or doubly saw-toothed to near base; stipules soon 

 falling; hairs (if any) white; buds shiny, sticky, brownish; 

 bark reddish; "berries" glossy, orange to scarlet, globe- 

 shaped, in dense, flat-topped clusters; seeds light brown, 

 oblong; shrubs to 13 feet high; Cascades, the only native 

 mountain-ash in Wallowa and Blue Mts., ne. Oreg., se. 

 Wash. 



Greenes mountain-ash (Sorbus scopulina) . 16 17 

 5. Leaflets 11 or less; stipules persistent; bark gray; Cas- 

 cades, Oreg., Wash.; not in Wallowa or Blue Mts. 



16 Natural hybrids between Saskatoon serviceberry {Amelanchier aim 'folia) 

 and Greenes mountain-ash found in the Wallowa Mts*., near Cornucopia, Oreg., 

 have been named XAmelasorbus jackii by the late Dr. Alfred Rehder in honor 

 of their discoverer and collector, J. G. Jack (Jour. Arnold Art). 6: 154. 1925). 

 ' Both Greenes mountain-ash and Cascades mountain-ash have been confused 

 by some authors with Sitka mountain-ash (S. sitchensis Roem.) and/or with 

 Siberian mountain-ash (S. sambucifolia Cham, tfc Schlecht.), neither of which 

 occurs in Oreg. or Wash. 



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