FOREST MANAGEMENT. 61 



tlie sulphur leafrolliT moth {Dichclia sulphureana Clem.), Teras fcrrH<jana S. Y., and Amorhia 

 li II, Hcrosaiia Clem. An interesting- species is the piuo tnhe-hn'Mev (Lophoilenis pnlitana Haw.), 

 which, in its larval stay;e, lives within a tube formed by webbiuj;; together a number of pine needles 

 as shown in fig. 1-4. 



A number of species of adult Coleoptera, whose larval habits are imperfectly understood, sub- 

 sist upou the leaves of White Pine. Of these are the Scarabicid, lUchtlonycha alhicoUis Burm., 

 and the Chrysomelid, GhjptoHcelis ])iibescens Fab. 



The best remedy fur the sawdy larva?,, caterpillars, and beetles is a spray of I'aris greeu, 

 applied upou the first appearance of tliese insects ou the trees. 



The consideration of the insect enemies of the White Piue may conclude Avith the mention of 

 the pine-leaf scale insect {Chionaspis philfoliic Fitch), which forms its scales upou the leaves, 

 exhausting them of their juices and causing them to turn yeUow. This species is illustrated at 

 fig. lo. 



A strong spray of kerosene emulsion will be fnuud an efticieut remedy against these scale 

 insects. 



FOREST MANAGEMENT. 



As regards forest management, we have, unfortunately, in this country no experiences whicli 

 would permit ns to form very positive ojiinions based on actual observation regarding this species 

 or any other. The study of the natural history of the species in its native occurrence permits us, 

 nevertheless, to dra^v conclusions which may at least serve as a basis for its future sylvicultural 

 treatment. 



In the first place, it may be declared that the White Pine is the most important and promising 

 species upon which to exjiend attention in our coming forestry operations within the limits of its 

 natural occurrence. Its adaptation to a variety of soils and situations within these limits, its rapid 

 growth, its excellent form, its remarkable mass development i>cr acre, its shade endurance, its 

 all-round nseful wood product, and its propagation, both by natural and artificial reproduction, 

 give it a position among our timljer trees hardly approached by any other. 



There are certain general princi]iles which are the result of experience in forest management 

 in Eui-ope aud elsewhere, apidying to this as to most species. The first is, that mixed growth is in 

 every respect superior to jiure growth ; it will therefore be proper policy to grow White Pine i^ref- 

 erably, if not altogether, in mixture witli other species. This advice is given in spite of the fact 

 that the White Pine grows rather well in pure stand, and th^it, owing to its shady crown during a 

 long period of its life and the density of stand in which it can develo^j, and the large <iuautity of 

 foliage which it sheds, the soil conditions are not in danger of deteriorating, as would be the case 

 with more light-needing species. But, as has been observed in its natural occurrence, its develop- 

 ment is more favorable in companionship, aud especially is this the case Mith regard to the 

 cleaning of the bole of its branches, which are peculiarly persistent. Whether it would pay to 

 substitute an artificial cleaning by pruning the young growths is still doubtful; meanwhile the 

 self-pruning performed by mixture with shady companions will have to be encouraged, especially 

 as thereby other valuable advantages are secured which attach to the mixed forest in general. 



Unfortunately, our irrational exploitation has reduced the White Pine in the natural forest areas 

 often to such an extent that its reestablishment is possible only by artificial means. Wherever 

 the culling has not been too severe, and either young growth has developed or seedling trees have 

 been left, the natural reproduction should be encouraged by favoring the young growth and by 

 removing or thinning out other species which interfere with the starting of a young growth. 

 Fortunately, the White I'ine, owing to its shade endurance, is specially fitted for natural repro- 

 duction from the seed of mother trees, more so than most other pines, and the rapidity of its 

 growth, in which it excels most other shade-enduring species, is also favorable in this respect. 



We are not yet prepared to determine the most profital)le rotation in which the species is to 

 be managed under varying conditions. The fact that it is not finly a very rapid but one of the 

 most persistent growers, trees making wood at the rate of li to 2 cubic feet per year up to the 

 one hundred and fortieth year, ])ermits a wide range of choice for rotations, and since its wood, 

 being rapidly changed into lieartwood, becomes serviceable very early, the rotations may be either 

 low or high, varying from fifty to one hundred aud fifty years, according to local economic and 

 soil conditions. 



