MAPLE FAMILY 153 



ACERACEAE. Maple Family. 

 Deciduous trees and shrubs with opposite simple leaves 

 palmately lobed in our species, and no stipules. 



1. ACER. Maple. 

 Flowers small, regular, in drooping racemes or short clus- 

 ters. Calyx 5-cleft. Petals five, or none. Stamens 3 to 10. 

 Ovary superior, 2-celled, becoming 2-winged in fruit. 



1. A. macrophyllum Pursh. Big-leaf Maple. Leaves 

 roundish, 4 to 12 in. across, on petioles 2 to 10 in. long, 

 palmately parted into 5 broad divisions which are again lobed 

 or toothed. Wings of the dry bristly fruit 1 to \y 2 in. long. 



The Big-leaf or Oregon Maple is a large, spreading tree 

 with smooth, green bark when young, becoming gray and fur- 

 rowed in age. It grows in moist places of the Yellow Pine 

 Belt, reaching an altitude of 5500 ft. near Nevada Falls, but 

 it is nowhere abundant. 



2. A. glabrum Torr. Sierra Maple. Leaves roundish, 1 to 

 3 in. across, on petioles 1 to 2 l / 2 in. long, parted less than 

 midway into 3 or 5 sharply toothed lobes. Wings of the 

 glabrous fruit ^ to 1 in. long. 



The Sierra Maple, also known as Dwarf Maple, is a slen- 

 der, graceful tree or shrub, 6 to 15 or rarely even 30 ft. high. 

 It grows on hillsides, often forming thickets, throughout the 

 pine belt of the Sierra Nevada, reaching 6800 ft. alt. on the 

 Glacier Point short trail. 



SAPINDACEAE. Buckeye Family. 

 Deciduous trees with opposite compound leaves and no stip- 

 ules, ovary superior, 3-celled, 6-ovuled, commonly only 1 

 ovule maturing. 



1. AESCULUS. Horse Chestnut. 

 1. A. calif ornica Nutt. California Buckeye. A small 

 spreading tree with gray bark. Leaflets 5 to 7, all from the 

 summit of the petiole, oblong, acute, 3 to 5 in. long. Flowers 

 I/2 in. long, white, showy, in clusters 4 to 6 in. long. Seed 

 1 or 2 in. across. — A well-known tree of western California, 

 extending up our canons as far as El Portal and probably to 

 Hetch Hetchy. 



RHAMNACEAE. Buckthorn Family. 

 Shrubs with simple leaves and small but often showy 

 flowers. Calyx-lobes, petals, and stamens 4 or 5 each. 



Fruit fleshy, berry-like; calyx free from ovary 1. Rhamnus. 



Fruit a dry capsule; calyx adnate to base of ovary 2. Ceanothus. 



