44 BULLETIN 1264, U. S. DEPARTMENT OF AGRICULTURE. 



these pests, though not invariably effective. To be successful, the 

 poisoned baits must be set when other food is scarce, and a much 

 larger region than the contemplated planting area must be covered 

 to take care of the animals that will wander in as soon as the newly 

 planted food becomes available. 



Porcupines. — Inasmuch as porcupines {Erethizon epixanthus) . 

 in addition to their other destructiveness, are given to gnawing 

 coniferous saplings and poles, either killing them outright by girdling 

 the trunk or seriously deforming them, they should not be permitted 

 to increase in the forests. They may be trapped successfully; 

 but, as in the case of other rodents, systematic poisoning is also a 

 very effective method of control. The common method of poisoning 

 is based upon the porcupine's well-known relish for salt. Brine- 

 soaked planks are sprinkled with strychnine and fastened to trees 

 above the reach of cattle, each bait board being sheltered from the 

 weather by a small roof of untreated board above it. 



SNOW MOLDING. 



" Winterkilling " is charged upon the records with an amount of 

 loss about equal to that from rodents and is a general term in report- 

 ing upon plantations used to include all kinds of losses, except those 

 from rodents, that occur during the winter months. Winterkilling 

 proper or loss due to excessive transpiration during periods when the 

 soil is frozen is rare. At the intermediate and higher elevations, the 

 snow comes so early and lies so continuously upon the ground that 

 the soil seldom freezes during the entire winter. Losses under 

 these conditions are more often the result of the heavy layer of deep 

 snow and the relative warmth of the soil. The snow-molding fungi 

 become very active and attack with frequently fatal results the newly 

 planted trees. Douglas fir and the spruces are the species most fre- 

 quently attacked, not only because they are usually planted at the 

 higher elevations where snow lies longest, but because they are 

 inherently more susceptible than the pines, as has been shown by 

 observation of nursery stock (2) . The heaviest damage is found where 

 the plants are bent over into intimate contact with the soil and litter, 

 the breeding ground of these weakly parasitic fungi. The best 

 remedy is to remove 1 or 2 square feet of leaf litter when planting 

 and to use only large vigorous stock that will stand firmly erect 



during the winter. 



INEFFICIENCY IN PLANTING. 



Poor work has been given as a frequent cause of failure, affecting 

 approximately 5 per cent of the administrative plantations. Careful 

 studies show that it is probably not a major factor but that it may 

 contribute largely to failure, particularly of plantations on somewhat 

 arid sites; since only by proper planting in deep holes can the root- 

 lets reach the plentiful water supply of the deeper soil layers before 

 the dry season overtakes them. Poor planting has been primarily 

 due to overemphasis of speed and a desire to show a low cost per acre. 

 The only remedy for this evil is a rigid insistence upon careful plant- 

 ing and the consideration of speed as a decidedly secondary factor. 



