272 PLANTS AND MAN 



Only three species of the once widely distributed bald cypress 

 genus remain, two found in the southeastern United States, and 

 the third in Mexico. The single species that is of considerable 

 economic importance in our country is the one bearing the group 

 name, bald cypress. It is most typically a swamp tree, being char- 

 acteristic of the deep swamps throughout the coast states from 

 Delaware southward to Florida, westward to Texas, and north- 

 ward in the Mississippi Valley to southern Illinois and Indiana. 

 It is a fairly large tree, commonly exceeding a hundred feet or 

 more in height, with diameters of three to five feet. The base of 

 the trunk is characteristically much swollen and buttressed, and 

 from the shallow widespreading surface roots arise conical 

 growths known as "knees" (fig. 191). These knees are regarded 

 by some botanists as an adaptation for living in water-saturated 

 soils, air difi'using into the projecting tissues and eventually 

 reaching the submerged root system. Although a typical swamp 

 tree, bald cypress shows best growth on moist, well drained sites, 

 but is excluded from the majority of such sites by its inability to 

 compete with the more aggressive hardwood species. It has few 

 associates in its habitat, the most common of which is tupelo 

 gum. The seeds, because of their weight, are not well scattered 

 by the wind, but this tree, like redwood, sprouts from the 

 stump and considerable reproduction is secured by this means. 

 The wood of the bald cypress is almost unbelievably durable, a 

 characteristic which, along with its workability and attractive 

 appearance, makes it a very valuable species. 



Incense Cedar 



Incense cedar (Libocedrus) has small, scale-like leaves which 

 are borne in alternating pairs and closely overlapping on the 

 branchlets. These are much flattened and result in the formation 

 of flattened sprays. The cones are small — about an inch long — 

 and composed of three pairs of thin woody scales, only the mid- 

 dle pair producing seeds. The bark on old trees is thick, brown 

 to reddish in color, fibrous, and deeply furrowed. 



Incense Cedar (fig. 192) is found in three western states — 

 Oregon, California and Nevada — where it grows mixed with 

 ponderosa pine, sugar pine, and white fir. The height of mature 



