18 American Midland Naturalist Monograph No. 4 



interior lakes, swamps, or bogs. Thickets of wax myrtle (Myrica gale) are 

 frequent along the lake shores and the swamps are usually filled with thick, 

 spongy carpets of sphagnum moss. Characteristic of these bog areas are small 

 trees of black spruce (Picea Mar. ana), white cedar (Thuja occidentalis) , 

 and eastern larch (Larix laricina) . A few of the shrubby associates are Lab- 

 rador tea (Ledum groenlandicum) , bog Kalmia (Kalmia polifolia), downy 

 andromeda (Andromeda glaucophylla), leatherleaf (Chamaedaphne calycu- 

 lata), and cranberry (Vaccin.um macrocarpon and V. oxycoccus) . 



Field Guide to the Trees 



I. Trees wth leaves linear or scale-like; fruits woody cones or 

 sometimes fleshy and berry-like. 



A. Trees with linear or needle-like leaves; fruits woody cones. 4 ....Pinaceae. 



I. Leaves flattened -linear, borne si'ng/p along ibe stems, the base not 

 surrounded fcp a sheath. 



Cones borne erect on the upper branches; twigs with round smooth scars after the 



leaves fall ABIES. 



Leaves spreading horizontally on the twigs, at least on lower branches. 



Leaves dark green above with two white lines on lower surface, rounded 



or often notched at tips; northern species, as to the national parks. 



Leaves in two series, the longer spreading in two ranks, the shorter 



pointing forwards and overlaying the others; in Pacific 



Northwest Silver fir (A. amabilis) . 



Leaves about equal in length, spreading opposite each other. 



Large trees 80 or more feet high with broad tops; cones gieen; 



in the Northwest Lowland while fir (A. grandis). 



Slender trees usually less than 50 feet high; cones purplish; 



eastern species Balsam fir (A. balsamea). 



Leaves dull green above, two white lines above and below, the tips 



rounded; found in California parks and the Southwest 



White fir (A. concolor). 



Leaves curving upwards, thus appearing crowded on upper sides of the 

 branchlets. 



Mature trees with more or less rounded tops ; cones oval to broadly 

 oblong-cylindric, 4 to 8 inches long. 



Cones wi;hout conspicuous bracts protruding from between the cone 



scales; in Lassen and Yosemite National Parks 



- California red fir (A. magnifica). 



Cones with conspicuous tongue-like bracts protruding from between 

 the cone-scales. 



Leaves ridged down the middle on both sides, thus somewhat 4- 

 sided ; found at Crater Lake, Kings Canyon, and 



Sequoia National Parks 



Shasta red fir (A. magnifica var. sbastensis). 



Leaves flattened and grooved down the middle on the upper side; 



occurs at Mount Rainier Noble fir (A. nobilis). 



4 California nutmeg {Torreya calif arnica) , a tree belonging to the yew family with 

 linear leaves and fleshy fruits, occurs occasionally in some California parks. 



