■■^" Field Manual 



(iJ. IJark with a resinoius or sticky milky sap; pith usually 

 large, if rather small then the bark aromatic. 63. 



• ijl. IJark not resinous. (i4. 



H;5. lUids clustered at the tip of the twig; bark spicy- 

 fragrant to the smell; base of petiole prominent 

 with several bundle scars; fruiting panicles 

 plumose. Cotinus. (44). 



<)8. Buds not clustered at the tip; bark often very poison- 

 ous to the touch; leaf scar partly surrounding the 

 bud; small trees or shrubs. Toxicodendron. (43). 



64. Terminal bud absent. 6o. 



(i4. Terminal bud present. 08. 



<io. Stipules or stipular scars absent uv indistinct. (it». 



d."). Stipules or stipular scars present. 67. 



6(i. Buds clustered at the tip of the twig; young twigs 

 glandular dotted. Myrica. (63). 



i)(h Buds not clustered at the tip; twigs not glandular: 

 bundle scars 3. Prunus, (27). 



<i<i. Buds not clustered at the tip; twigs not glandular: 

 bundle scars numerous; outer bud scales 2. 



Koelreuteria. (39). 



()7. Buds and twigs vt^vy downy, twigs dark brown or 

 black. Cydonia. '(24). 



67. Buds downy or pubescent; twigs glabrous or pubes- 

 cent, gray or brown. Rhamnus. (34). 



(iS. Twigs green or yellowish-green, glabrous; internodes 

 very unequal; lateral buds minute; small trees. 



Cornus. (7!»). 



lis. Twig> normally red aboxe and green beneath, 

 glabrous: bark very bitter: some axils with 2 or 3 

 hairy buds of nearly equal size: trees. 



Amygdalus. (28). 



(iS. Twigs not green or red and green unless the plants 

 are low shrubs, but gray, brown, black, or reddish. 

 60. 



<i!t. Bundle scars o or more in the broad U-shaped leaf 

 scar; tips of the buds quite downy: small trees. 



Sorbus. (21) 



69. Bundle scars 3. 70. 



"'•. Buds rounded at the apex, often clustered at the tip 

 of the twig: twigs glandular dnttcfl. Myrica. (63). 



