BULLETIN 1007, U. S, DEPARTMENT OF AGRICULTURE. 
Table 2. — Properties of yellow poplar, cottonwood, and white pine compared with 
basswood. Bassivood=100. 
Shrinkage from 
Strength at 12 
Weight 
green to oven-dry 
condition. 
per cent mois- 
ture. 
Composite values. 
Mod- 
Compres- 
1 
Species. 
Oven- 
ulus 
sion par- 
allel to 
grain 
(maxi- 
mum 
dry 
(spe- 
cific 
grav- 
Air- 
dry. 
Green 
In vol- 
ume. 
Ra- 
dial. 
Tan- 
gen- 
tial. 
of 
rup- 
ture 
in 
Strength 
as a beam 
or post. 
Hard- 
ness. 
Shock- 
resist- 
ing 
ability 
Stiff- 
ness. 
ity.) 
bend 
ing. 
crushing 
strength). 
Yellow poplar.. 
112 
104 
93 
72 
62 
74 
105 
Ill 
114 
128 
103 
116 
Cottonwood 
112 
108 
120 
89 
59 
99 
96 
105 
102 
119 
134 98 
White pine 
109 
104 
95 
49 
33 
63 
102 
119 
116 
128 
109 1 100 
Basswood is rated low in durability. The estimated average life 
of untreated basswood lumber, under conditions subjecting it to 
decay but not to mechanical wear, is placed at from 3 to 5 years. 
Its length of life in any particular case may, of course, vary from 
this, depending on conditions. If properly treated with coal tar 
creosote, or some other standard preservative, its durability may be 
greatly increased. 1 
STRUCTURE. 
Basswood is a diffuse-porous wood (PI. I). The pores are about 
uniform in size and quite evenly distributed throughout the annual- 
growth ring. They are, however, somewhat less numerous near the 
outer limits of each annual ring, and this makes a contrast with the 
greater number of pores at the beginning of each ring so that the 
growth rings can be quite readily distinguished on a smoothly cut 
transverse section. Medullary rays are generally not conspicuous on 
longitudinal surfaces; in some pieces, however, they are reddish and 
quite conspicuous on a quarter-cut surface; on a smoothly cut trans- 
verse section they can be readily distinguished without the aid of a 
lens. 
IDENTIFICATION. 
In appearance basswood resembles somewhat yellow poplar, 
cottonwood, buckeye, and tupelo. The yellow poplar, however, can 
be distinguished by its yellow T ish-brown heartw r ood, which has a 
characteristic greenish tinge. In cottonwood the medullary rays 
are very fine and barely visible even with a hand lens on a smoothly 
cut transverse surface, in contrast to those in basswood, which are 
visible to the unaided eye ; the pores of cottonwood are conspicuously 
larger than those of basswood, as seen under a hand lens, and cotton- 
wood generally has a "woolly" texture on sawed surfaces. In 
buckeye and tupelo the rays are also finer than in basswood. The 
brownish-black, longitudinal streaks occasionally found in the heart- 
wood help to distinguish basswood. 
1 Farmers' Bulletin 744, Preservation of Farm timbers, gives methods of treatment. 
