air-dry material. These data were obtained from specimens of the sizes used 
for Forest Products Laboratory tests. They have been converted from metric 
system units and adjusted to 12 percent moisture content to make them compara- 
ble to data available on familiar United States species. Other test data from 
India, Malaya, and the Philippines have been reported elsewhere but are based 
on specimens of different sizes with different moisture content values or are 
in different units (10, 13, 21, 26, 29). 
Seasoning and Shrinkage 
Comprehensive seasoning information is not available for apitong. The range 
of variation in density and resin content of the material sold in world markets 
as apitong is considerable. It is believed, however, that with the careful 
use of modern drying methods apitong can be adequately seasoned, in spite of 
the fact that it has had a reputation for being slow to dry and somewhat refrac- 
tory with notable tendencies to warp, check, split, and collapse (4, 5> 21) . 
Air seasoning (2) or air seasoning prior to kiln drying have both been used 
with this material. 
The British Forest Products Research Laboratory has recommended relatively 
mild treatment for apitong, starting with temperatures of 110° or 120° F. and 
85 percent relative humidity (Schedules Nos. 4 and 5> Leaflet No. 42, "Kiln 
Drying Schedules," 1949). The U. S. Forest Products Laboratory in its 1951 
"Schedules for the Kiln Drying of Wood" (Forest Products Laboratory Report 
No. D1791) lists as a generally applicable mild schedule, T3-B1, which has been 
suggested for use with green apitong. Schedule T5-C2 in this report would pro- 
vide a more severe schedule if conditions appeared to warrant it. 
As an effective general procedure for minimizing warping, a sticker spacing of 
not over 18 inches, with all stickers in vertical alinement, and weighting down 
of the top of the pile has been used. 
Shrinkage figures recorded (26) for apitong are: 
Radial Tangential Longitudinal Volumetric 
(Percent) (Percent) (Percent) (Percent) 
Green to air-dry 2.3 6.7 0.1 8.6 
Air-dry to oven-dry 2.6 4.9 0.1 7.4 
Workability 
Working characteristics vary considerably among the different species of 
Pipe p ro carpus and even within the same species, as influenced by growth 
conditions. The woods are generally considered as moderately difficult to 
work. The presence of silica (4, 5) and gum may give some trouble from 
blunting of cutting edges or clogging of saws (3, h, 5, 34) . A good finish 
and polish, however, can be obtained, especially in thoroughly dried material 
(l4, 21). Exceptionally resinous material is troublesome, for example, in 
Report No. R1920 -4- 
