82 BULLETIN 1105, U. S. DEPARTMENT OF AGRICULTURE. 



In all of the preceding discussion it lias been assumed that re- 

 production is lacking at the time of cutting. There are extensive 

 areas, however, which are well stocked in advance of cutting. Under 

 such conditions the reproduction problem is greatly simplified, since 

 all that is necessary is to leave a few seed trees to stock the open- 

 ings created by cutting (usually no reproduction occurs directly 

 under the trees, though there are exceptions to this rule), and to 

 provide adequate protection against fire and grazing. Some damage 

 is to be expected in logging, but experience has shown that ordi- 

 narily this is not serious. The advantages of advance reproduction 

 are so great as to warrant special efforts to encourage the estab- 

 lishment of seedlings in virgin stands in which cutting is con- 

 templated. Because of the enormous quantities of seed produced 

 in a virgin stand, reproduction can be secured in a much shorter 

 time before cutting than after cutting. The seedlings will grow 

 slowly in a virgin stand, and those nearest the trees are likely to 

 be shaded out; nevertheless, the presence of a good crop of seedlings 

 at the time of cutting is a valuable asset. With adequate protection 

 against fire and regulation of grazing, the open spaces in most 

 virgin stands could be stocked in about 10 years, and by properly 

 timing the cutting with reference to seedling crops, even the seed- 

 lings under groups of old trees could be saved. 



SUGGESTIONS REGARDING PRESENT PRACTICE IN CUTTING. 



How do the foregoing conclusions affect present silvicultural 

 practice? This question can best be answered by quoting the in- 

 structions for marking western yellow pine in the Southwestern 

 District, and adding such comments as seem warranted by the in- 

 formation brought to light in this investigation. 



Pkinciples of Standard 

 Masking Pkactice in Western Yel- 

 low Pine, District 3, January 10, Comment. 

 1917. 



The basic standard. — All marking The principle governing the removal 



will be done with the primary object of yf trees is that the relatively young 



meeting the silvicultural requirements ui„„,,.„„j, <,iionld be left in nreference 



of the stand. So far as present in- blackjack shouici De lett m piereience 



formation indicates, this can be most to the mature or overmature yellow 



uniformly accomplished by the adop- pine. Intermediate trees represent 



tion of the following standard: the transition stage between black- 



(1) Yellow pine tre^s as distinct ^^^.j. ^^^j ^^q^^, ^^^ j^^ marking, 

 from blackjacks which have passed t T i. i „n u + ^ +^.1 

 the period of rapid growth, will be intermediate trees should be treated 

 marked for cutting except where, in as blackjacks since they are still in 

 the absence of younger and better the stage of active growth. When- 

 trees, they are necessary as seed trees ^^^^ ^^-^^^^ jg ^^^ ^^^^^ ^^ to whether 

 or to afford protection or shelter for . .. . ^ , . n„„,-:i„^i, „.. „ ^^i 

 reproduction to establish itself. '^^ individual is a blackjack oi a yel- 



(2) Blackjacks and rapidly growing low pine, a safe rule is to call it a 

 intermediate trees will be left except blackjack. The foregoing refers to 



