Brief Key to the More Common Genera of Conifers Found 
Growing in the Brooklyn Botanic Garden and Vicinity, 
Based on Leaf Characters. 
A. Leaves evergreen. 
1 . Leaves secondary (borne on spur shoots) . 
a. Leaves borne on short spur shoots in 2s-6s, 1 to 15 
inches long Pins (Pittas). 
b. Leaves linear, 1 to 3 inches long, borne on branch- 
lets in large, alternate clusters 
Cedar of Lebanon ( Cedi its) . 
c. Leaves in whorls of 20-30 to each branchlet, 2-4 
inches long - - Umbrella Pine (Sciadopitys) . 
2. Leaves primary ( borne directly on the main axis). 
a. Leaves £ to 1 inch long, many ranked, 4-sided 
Spruce (Picea) . 
b. Leaves 1£ to 3 inches long, many ranked or often 2- 
ranked, flat, with blunt tip, fastened to the cylin- 
drical stem by a disc-like base - Fir (Abies). 
c. Leaves short petioled, linear, £ inch long, obtuse, 
dark-green above and white beneath, appearing 
2-ranked Hemlock ( Tsuga) . 
d. Leaves strong-scented, small, scale-like or awl- 
shaped, closely appressed and overlapping 
White Cedar, or Ground Cypress (Chamaecy paris) . 
e. Leaves needle-shaped, rigid, in whorls of three, 
£ inch long - Common Juniper (Juniperus communis) . 
f. Leaves very small, awl-shaped, appressed, dark- 
green - - Red Cedar (Juniperus virg ini ana) . 
g. Leaves of two sorts; one awl-shaped, the other scale- 
like and appressed, making a fan-like spray - 
Arbor Vitae ( Thuja). 
h. Leaves needle-shaped, \ of an inch or less long, 
sharp-pointed, scattered spirally around the 
branches, mostly appressed - - - - - 
Mammoth Tree (Seqouia gigaulea) 
i. Leaves £to } inch long, roundish, smooth, 2-ranked, 
flat - California Red-wood (Sequoia setnpervirens) 
k. Leaves 1 to 2 inches long, awl-shaped, rigid, closely 
overlapping, completely covering the thick stems 
in whorls of 6 to 8 
Norfolk (or Chile) Pine ( Araucaria ) 
