GENERAL CONDITIONS 33 



chusetts, Rhode Island and Connecticut will effectually check 

 the disease. As compared with the capital invested in white 

 pine timber and woodworking plants the value of all the culti- 

 vated currants is practically negligible. Red pine and pitch pine 

 are subject to a similar native blister rust which has as its alter- 

 nate host sweet fern, but fortunately this disease is not so virulent 

 as the imported white pine blister rust. 



Another fimgus which occasionally kills white pine is the 

 bracket fimgus, Trametes pini, or red rot This is a heart rot 

 which enters thru a dead limb and destroys the tree by eating 

 away the heartwood. Sapwood it cannot attack. But the decay 

 of the heartwood leaves the tree without a backbone, so to speak, 

 and the wind tumbles it over. The wood of such a tree is, of 

 course, useless since there is but a shell of soimd sapwood around 

 the rotted heartwood. It is, however, usually possible to get one 

 or more sound logs from an infected tree because the fimgus com- 

 monly enters near the ground and works within a limited area. 

 To prevent the spread of this parasite all infested trees should be 

 removed as quickly as possible. 



Another imported pest is the gyi>sy moth. WTiile the larvae 

 cannot feed on conifers for the first week after hatching they can 

 and will defoliate white pine, red pine and hemlock if they get 

 started on hardwood. Consequently stands of gray birch and 

 white or red pine offer ideal conditions for its development. AU 

 the egg clusters laid on the gray birch have the proper kind of 

 food to give them a good start so that after the first week the 

 larvae are able to digest coniferous foliage. In the indi\'idual 

 woodlot there are two methods of control. By all odds the best 

 way is to cut out the hardwoods because they can usually be 

 made to >deld some returns as cordwood at least. Painting the 

 egg clusters in the winter with creosote is effective if thoroly done 

 but the expense is usually prohibitive in large lots. It is diflScult 

 and time consuming to climb thru a large oak for example. Such 

 methods, while justified for shade trees, are usually not feasible 

 for woodlots. 



White pine is attacked by two forms of plant lice — Chermes — 

 which occasionally become abimdant enough to disfigure or even 



