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BULLETIN 1105, U. S. DEPARTMENT OF AGRICULTURE. 



5. Where adequate reproduction is 

 established, but is less than the pole 

 stajje, and there are few or no black- 

 jacks or intermediate trees. 



(a) Yellow-pine seed trees should 

 be left as safety trees, if the bulk of 

 the reproduction is less than two (2) 

 feet in height, and where needed to 

 seed in or shelter blank areas. 



(&) All yellow pines may be cut if 

 the area is well stocked with repro- 

 duction two (2) feet and over in 

 height. 



ital on account of relatively slow 

 growth and greater susceptibility to 

 lightning, windthrow, and decay. Re- 

 cent investigations, however, show that 

 few trees under 25 inches in diameter 

 have reached the highest stage of seed 

 bearing. In view of this fact it seems 

 advisable to revise the instructions so 

 as to provide for at least four trees 

 per acre where the diameters fall be- 

 tween 21 and 25 inches. If all the 

 trees measure over 25 inches, and if 

 they are well selected, two per acre 

 may suffice ; but three per acre is pref- 

 erable, especially if some individuals 

 are not strictly up to standard. In 

 such cases too much emphasis can not 

 be placed upon the importance of 

 selecting the very best seed trees 

 available. A first class seed tree in 

 the yellow-pine class may yield 10 

 pounds of seed in a single year, 

 whereas a poorer seed tree of equal 

 diameter, representing an equal invest- 

 ment in timber value, and drawing an 

 equal amount of moisture, needed by 

 young growth, may in the same year 

 produce only 1 pound of seed. 



In addition to blanks which may 

 exist prior to cutting, provision should 

 be made for seeding up the open 

 spaces which are created by the re- 

 moval of trees. Underneath and ex- 

 tending from 20 to 40 feet around 

 large tree groups, the ground is usu- 

 ally bare of seedlings as well as her- 

 baceous growth. These spaces afford 

 ideal conditions for reproduction after 

 the trees are felled, provided they are 

 well seeded and grazing is properly 

 regulated. Where the group arrange- 

 ment is strongly developed, these 

 spaces, or stump patches, may occupy 

 25 per cent of the total ground area 

 after cutting. 



As in the above case, provision 

 should be made for seeding the stump 

 patches created by felling large groups 

 of trees. Usually there will be enough 

 large blackjacks for this purpose ; 

 nevertheless, the matter should be kept 

 in mind. 



