9G Di:S( 1MPT10XS OF THE SHRUHS 



KEY TO THE BUCKTHORNS 



* Leaves opposite and serrate ; plants usually thorny ; fruit black, 



i inch broad. (A.) 



A. Leaves broad at base, sometimes heart-shaped. COMMON Hi < K- 

 TIIOKX (83) Rhainiuis cathartica, 



A. Leaves narrowed at base. DAHURIAN BUCKTHORN Rhamnns 

 dahiirica. 



* Leaves alternate ; plants not thorny ; winter buds scaly ; petals 4 or 



more. (B.) 



B. Leaves evergreen ; hardy only South ; shrubs or small trees to 20 

 feet. (C.) 



C. Twigs somewhat hairy ; leaves orbicular, dentate ; fruit red. 

 KKD-FRUITED EVERGREEN BUCKTHORN (84) - - Rhamnus 

 crocea. 



C. Twigs smooth ; leaves oval ; fruit nearly black. BI.ACK- 

 FRUITED EVERGREEN BrcKruoRN (85) Rhamnus Alater- 

 nus. 



B. Leaves thinner and deciduous with many side-veins, 10-20 

 paiis; fruit black. (D.) 



D. Twigs smooth ; leaves pale green, 2-0 inches long. MOUNTAIN 

 BUCKTHORN Rhamnus alpina. 



D. Twigs pubescent ; leaves brownish when mature, 3-9 inches 

 long. LKHAXON BUCKTHORN (80) Rhamnus libanotica. 



B. Leaves deciduous with but few side-veins, 4-0 pairs; fruit 

 I. lack. (E.) 



E. Wide-spreading shrub to 4 feet ; fruit with 3 nutlets. ALDER- 

 I.I.AVED BUCKTHORN (87) Rhamnus alnifolia. 



E. Tall erect shrub to 8 feet ; fruit, with 2 nutlets. LANCE-LEAVED 

 'BUCKTHORN (88) Rhamnns lanceolata. 



* Leaves alternate ; plants not thorny ; winter buds naked, not scaly ; 



petals 5. (F.) 

 F. Leaves thiekish, nearly evergreen, 1-7 inches long; fruit red 



changing to black. (G.) 

 G. Leaves with notched and often wavy margins. COFFEE-BERRY 



- Rhamnus Purshiana. 

 G. Leaves about entire. C'AKOI.INA BUCKTHORN or INDIAN 



1 CHERRY' (SO) Rhamnus caroliniana. 

 F. Leaves thinner and smaller, 1-3 inches long ; nutlets 2. AI.DKR 



BUCKTHORN (00) Rhamnus Frangula. 



F. Leaves linear with undulate edge ; nutlets 2. FERN-LEAVED 

 l'.i < KTHORN (91) Rhamnus Frangula aspleniifolia. 



