SAMPLE PLOTS IN SILVICULTURAL RESEARCH 33 



calls for studies to determine the time of active growth as a basis for 

 choosing both time of treatment and time of measurement. 



In general, treated plots should be subjected to the same treatment 

 accorded the stand of which they are samples. However, while 

 there is bound to be more or less accidental injury to the reserved 

 stand in felling and logging, sufficient care should be taken on the 

 plot not to cause damage that will vitiate the purpose of the study. 



Cultural measures should be carried out in such fashion as to do 

 the least possible injury to the remaining trees or to other vegeta- 

 tion on the plot. Large trees removed should be so cut as not to 

 rake the boles or break the tops or branches of reserved trees. Trees 

 lodged in the tops of their neighbors should be removed if at all 

 possible. In machine logging or skidding, reserved trees should be 

 cushioned by encasing the lower end of the bole with a stockade 

 of stout poles firmly tied to the tree. 



Cutting on sample plots should be done as neatly as conditions 

 permit. On larger trees the saw should be used in preference to 

 the ax. In stands of very small trees cutting should be done with 

 a machete or pruning shears, which make a clean, sharp cut. In 

 pruning operations cuts should be made close to the stem, so that 

 they will heal over promptly and without injury to the stem. Xeat 

 cutting calls not only for good workmanship but for sharp tools. 



Locations for skid roads and trails should, if possible, be selected 

 before cutting is begun, and felling should be so conducted that skid- 

 ding will cause the least possible injury to reproduction or to sub- 

 ordinate vegetation. If skidding is to be done in the winter, areas 

 that are to be specially protected from damage should be designated 

 in advance of snowfall. If erosion is likely to develop as a result 

 of skidding operations, the areas dragged bare should be covered 

 with a heavy layer of litter unless the project includes study of 

 conditions on areas bared by skidding. 



The trunks and heavier branches of trees cut on a plot and its 

 isolation strip should, if possible, be removed from the plot area. 

 If not utilized they should be burned, or so treated as not to invite 

 insect attack. Such material should not be placed in piles. 



Slash resulting from any cultural work constitutes a menace to 

 plot safety if left untreated. In most instances slash should be 

 burned, if this can be done without damage to the reserve stand. 

 If slash must be burned on the plot, the safest method is to burn 

 it in a few small piles as cutting proceeds. Care should be taken 

 to prevent a fire on a plot from spreading, and to avoid placing so 

 much material on the fire at any one time as to cause scorching of 

 crowns or heat-killing of buds or leaves. Care should be taken, 

 also, not to place piles so close to reserved trees that the heat from 

 their burning will kill the cambium through the bark; such injury 

 causes the formation of hidden fire scars and distorts diameter 

 growth. If possible, a supply of water should be kept at hand to 

 prevent the spread of fire, to cool down fires that become too in- 

 tense, and to control fires that escape. In regions of heavy snow- 

 fall, slash can be piled and burned with minimum damage to the 

 reserved stand while the ground is covered with snow. 



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