ORGANIZATION AND METHODS OF THE TIMHI'R liXAMlNATIONS IN THE DIVISION 



OF FORESTRY. 



The (imlior examinations recently be.iinn under tiie direction of the Division ol' Foicsiry have 

 for their object to determine more precisely than has ever been done the mechanical, physical, and 

 chemical properties of the most important American timbers and the relation of these iiropcrdcs 

 to each other. IJesides more reliable data rejiarding the properties of onr princi])al timbers, tlicrc 

 i.s to be gained from this investifiatiou a means of determinins' (piality by the examination of 

 physical appearance and structure, aud of establishing- an interrelation between (|nality and 

 conditions of growth. 



To define the objects of the work more in detail, some of tlic (pu'stioiis which it is expected 

 ultimately to solve may be formulated as follows: What are the essential working properties of 

 onr various woods and by what circnmstances are they inthwiiccd ? Ibtw does age, rapidity of 

 growth, time of felling, and aftertreatnient change (iiuility in (liU'crciit tindx'rs? In what relation 

 does structure stand to (juality? How far is weight a <Titciion «il' sticngth.' What macroscoi)ic 

 or microscopic aids can he devised for deternuning (piality from |)hysical examination:' What 

 difference is there in wood of different parts of the tree? IIow far do climatic and soil ((inditions 

 influence quality? In what respect does tapping for turpentine afl'ect (piaiiiy of pine timber.' 



There are four departments necessary to carry on the work as at present organized, namely: 



(1) The collecting department. 



(2) The department of mechanical tests. 



(3) The de])artment of physical and microscopic, examination of the test material. 

 (-1) The department of compilation and final discussion of results. 



The region of botanical distribution of any one species that is to be investigated is divith'd 

 into as many stations as there seem to be widely different climatic or geological ditVerences in its 

 hal)itat. In each station are selected as many sites as there seem widely different soils, elevations, 

 exposures, or other striking conditions occupied by the sjjecies. An expert collector describes 

 carefully the conditions of station and site, under instructions and on blanks ap])ended to this 

 rc^jort. From each site five mature trees of anyone s])ecies are chosen, four of which areavei-age 

 representatives of the general growth, the fifth, or "check" tree, the? best de\('loi)e(l that can he 

 f(mud. The trees are felled and cut into logs of merchantable size, and from the butt end of each 

 log a disk 6 inches in height is sawed. Logs and disks are marked with numbers to indicate 

 luimber of tree and nnml)er of log or disk, and tlu^ir north and south sides are marked ; their lieiglil 

 in the tree from the ground is noted in the iccord. The disks are also weiglied immediately, then 

 wrapjx'd in oiled paper and |>ackinu pajiei', and sent by mail or ex])ress to the labr»ratory, to serve 

 the ])ur]ioseof (jhysical and structural examination. .Some disks of tlie limhwood and of younger 

 trees are also collected for otiier physical and [)hysi(dogical investigations, and to serve with flu- 

 disks of the older trees in studying the rate of growth and other problems. The arduous work of 

 collecting has been done hitherto chieliy by Dr. Charles Mohr, of Mobile, Ala., and has been con- 

 fined so far mainly to the (•ollecfion of i)ines and oaks from Alabama, of which during the year one 

 hundred aiul forty-nine trees were collected, luadditmn. twenty-two trees of white pine lidni 

 ^^'isconsin were collected. 



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