654 



ACERACEAE 



Staphylea 



o 5o 



Map 1360 



Celastrus scandens L 



161. STAPHYLEACEAE DC. Bladdernut Family 

 4665. STAPHYLEA L. 



1. Staphylea trifolia L. American Bladdernut. Map 1361. An infre- 

 quent shrub in all parts of the state. It is restricted almost entirely to the 

 slopes and alluvial banks of streams, and only rarely is it found in low 

 places in woods. 



Que. to Minn., southw. to N. C. and Kans. 



163. ACERACEAE St. Hil. Maple Family 



4720. ACER [Tourn.] L. 



Leaves 3-foliolate or pinnate. 



Branchlets green, not glaucous; fruit more or less pubescent until maturity 



1. .4. Negundo. 



Branchlets glaucous and usually more or less violet when rubbed ; fruit glabrous. 



la. A. Negundo var. violaceum. 



Leaves simple. 



Flowers appearing before the leaves; fruit maturing in May or June. 



Petals none; fruit more or less pubescent at maturity; the terminal lobe of the 



leaves usually narrowest at the base 2. A. saccharinum. 



Petals present; fruit glabrous at maturity; the terminal lobe of the leaves usually 



broadest at the base. 



Branchlets glabrous at maturity; leaves at maturity glabrous beneath except 



for a few hairs in the axils of the veins or rarely the entire lower surface 



covered more or less with a short pubescence; mature fruit generally 2-3.5 



cm long 3. A. rubrum. 



Branchlets more or less pubescent at maturity; leaves beneath covered with a 

 dense tomentum which remains until maturity or sometimes becoming 



scanty; fruit generally 4-5 cm long 3a. A. rubrum var. Dmmmondii. 



Flowers appearing after the leaves; fruit maturing mostly from July until 

 September. 

 Leaves yellow green beneath, the sides usually somewhat drooping; petioles of the 

 terminal pair of leaves with expanded and more or less clasping bases (some- 

 times these appendages late in developing.) 



