49 



Tliesomidness or otherwise of a tree cannot always be determined, f»ad mnny 

 trees which are unsound at the base may be sound throughout the greater part of the 

 stem. 1'rees are generally classed as unsound if they are notieeably decayed or hol- 

 low in the stem ; if they have half-dead crowns, or arc stage-headed ; or if they give 

 back a kul'ow round when struck with an axe by a man standing on the ground. 



Where tlie enumeration is to be complete, and net by 

 linear survey or sample plots, the record should be prepared 

 separately for compact areas not exceeding a few hundred 

 acres in extent. Eorthe purpose of checking the enumera- 

 tion certain areas or plots should he selected for re-survey,, 

 and the officer in charge should be present during at least 

 one day's recording in each plot and should add the record 

 made by himself to that made before his arrival. By keep- 

 ing a careful account of the number of tickets issued and 

 of the number returned, the balance that has been expended 

 of each kind is known, and these numbers afford an addi- 

 tional rough check on the number of each kind of tree- 

 But, unless the countings are actually verified, tickets may 

 be either accidentally lost or intentionally made away with,, 

 and the record may be completed accordingly so as to lead 

 to the belief that a large amount of work had been accom- 

 plished. Constant and careful supervision by a trustworthy 

 person is, in fact, the only means by which reUable results 

 can be secured. 



It is usually the custom to blaze with an axe the trees 

 measured. This, however, for obvious reasons, should not 

 be done so as to injure the stems in the manner usual with 

 native workmen. Where water is available, the trees may 

 be marked with whitewash, made loith rice water so as to 

 render it adherent ; but ordinarily a light blaze on the bark 

 of each tree will suffice. 



In crops consisting of fairly regularly shaped -and not very large trees the 

 mpasurement of a single diameter mav suffice, especially if the crop is traversed by 

 the enumerating party ia various directions. But otherwise the mean of two diame- 

 ters, taken more or less at right-angles to one another, should be recorded. Althoogh 

 a matte- of petty detail, it is necessary to observe that the cahpers should be properly 

 applied to the trunk of the tree and the diameter read off before the instrument is removed. 

 The diameters should be all measured at breast-height, and on hill-sides this height 

 should be taken on the upper side of the stem. Breast-height has been assumed to be 

 4i feet ; but, as the boles of trees do not taper either regularly or very rapidly, it is not 

 necessary that this height should be exactly measured before the calipers are applied- 

 Sufficient accuracy is attained if the measurer is careful to hold the calipers horizon- 

 tally at the height of liis chest, and if the diameter is measured at any height between 

 4 and 5 feet and at a place where the stem is free from excrescences and branches. 

 When a tree divides into two or three main stems, near the pomt at which the calipers 

 would ordinarily be applied, each stem should be measured separately. 



Where the enumeration is to be complete, the survey should, if possible, be effect- 

 ed over successive nairow strips, each strip being gone over once and in a direction 



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