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[ClIiCULAR No. 9.] 

United States Department of Agriculture, 



In Circular 8 of the Forestry l)ivi.sioii, published about a year ago, it was stated 
that tests made on timbers of Longleaf Pine, bled or unbled, lent countenance to 
the belief that bled or tapped timber did not sutler in strength by virtue of the 
tapping. Further tests and examinations permit now the announcement without 
reserve that the timber of Longleaf Pine i.s in no irn.i/ affected bi/ the tapj>tnr/ for turpen- 
tine. This refers to its mechanical as well as chemical pro]ierties, and hence even 
the reservation that it migiit suffer in durability is now eliminated and any preju- 
dice against the use of bled timber in construction, wherever the unbled timber 
has been considered desirable, must fall as having no found;ition in fact, i)eing 
based only on vague belief, proved to be erroneous. 

It is to be hoped that this fact will be made widely known among builders, 
architects, and engineers who have hitherto made discrimination against bled tim- 
ber and thereby depreciated or discouraged the manufacture and impeded the sale 
of an article which answers all the purposes of construction and the unrestricted 
use of which is dictated by true economy. 

The basis for the statement i-egarding the mechanical ijroi>erties is furnished 
by a series of tests comprising not less than 300 tests on 32 trees of this Pine, l)led 
and imbled, from various localities. 

The somewhat puzzling fact that bled timber exhibited, if anything, greater 
strength in the tests has been accounted for by the fact that the turpentine 
orchards are located mostly on sites which produce better quality timber as well 
as larger yield of tui'pentine. 

To determine whether any changes in the chemical composition take jslace, a 
series of chemical analyses of bled and unbled timber has been made, which 
indicates that the resinous contents of the heartwood are in nowise affected by 
the bleeding, the oleoi'esins of the heartwood being non-fluid, the whole turpentine 
tiow is confined to the sapwood. 

Among other interesting facts regarding the distribution of resinous contents 
through the tree which will be published in a separate bulletin, it ajipears that 
trees standing side by side and to all appearances in similar conditions show very 
varying quantities of resinous contents. 

To make sure that experience did not, if sifted down, contradict the results 
of these investigations, a competent agent, Mr. F. Eoth, visited turpentine orchards 
and sawmills in the Longleaf Pine region. He reports that nobody was found — 
although it was claimed by some — able to discern any difference in "the appearance 
of the bled and unbled timber ; that in spite of consumers' specifications for 
unbled timber, they are almost invariably served with a mixture without finding 
it out ; that experience in the districts where bled timber is cut and used has not 
sustained the claim of inferiority. 

This information is furnished in advance of the full report on the investiga- 
tions in question, in order to remove as quickly as possible the unwarranted dis- 
crimination against the product of nearly one million acres of Southei'n pine, 
which are annually added to the total acreage in turpentine orchards. 

This result of authoritative investigation should be worth several million dol- 
lars to the forestry interests of the South, permitting readier use and sale for a 
product that left uncut endangers the future of the forest by the destructive 
conflagrations to which it is specially subject. 

B. E. Feknow, 

CJdef of Difuision. 
Approved : 

Edwin Willits, 

Assistant Secretary.