J JO THE PRINCIPLES OK HANDLING V.OOULAXUS 



cutting, with oak, maple, and other hardwoods. If the 

 original stand was a mixture of white pine and hard- 

 woods, many of the latter send up vigorous sprouts, 

 which practically maintain the proportion of hardwoods 

 in the future stand, and it becomes difficult to increase 

 the proportion of pine. In pure white-pine stands there 

 is also a tendenc\- toward a replacement by hardwoods 

 because of the great abundance of seed on the ground, 

 and of young seedlings alreadx' started under the pines. 

 This tendency can partly be overcome b\' burning over 

 the ground. Where, however, the hardwoods are estab- 

 lished as the principal growth, pine creeps in underneath 

 them in a few years, provided there are trees to furnish 

 the seed. 



The system of scattered seed-trees is applicable also 

 to the second-growth stands of loblolh' and other \'el- 

 low pines in the South; in certain instances to second- 

 growth Douglas fir stands on the I'acific Coast; and, 

 where the conditions of moisture are favorable, to cer- 

 tain stands of pure \\'estern yellow pine. 



It is a system more commonh' applicable in second 

 growth than in a virgin forest, because in the former the 

 investment in securing reproduction ma\- be brought 

 within a reasonable amount, while in the \irgin forest it 

 IS difficult to find seed-trees of the right character which 

 do not represent so great an investment as to make the 

 system impracticable. 



Reserving Groups of Seed-Trees. — In exposed sites it 

 is often not practicable to leave isolated seed-trees, because 



