A NATIONAL PLAN FOR AMERICAN FORESTRY 1495 



have shown that seedlings of Norway pine from various geographical 

 and climatic seed sources show marked differences in hardiness and 

 early growth. 



Many North American tree species have a wide geographical dis- 

 tribution and it is inevitable that unsatisfactory results will come, 

 as they already have, from indiscriminate use of their seed. Pon- 

 derosa pine with a natural range of some 400,000 square miles of 

 territory furnishes innumerable sources of seed. Experimental 

 plantations of ponderosa pine from several seed sources, established in 

 the Sand Hills of Nebraska, in Colorado, in the northern Rockies and 

 at Wind River in southern Washington, show differences, some slight 

 and intangible as yet, some marked, that leave little doubt as to the 

 importance of seed source in forestation. 



Much could be written on the past development of forest-nursery 

 technique and the problems still to be worked out through research 

 and practice. It should suffice in the present instance briefly to indi- 

 cate the basis for confidence in future progress. 



Nursery methods have been so developed that a consistent output 

 of good quality stock at reasonable cost is now possible. Numerous 

 factors contribute to these lowered costs, including favorable watering, 

 fertilizer, and effective soil management practices. Damping-off, 

 other diseases and chlorosis are rapidly being overcome. Better 

 stock for a given purpose has been produced by obtaining proper 

 densities in seed beds, root pruning, improved soil fertility, and by 

 other means. As an illustration, the Savanac Nursery on the Cabinet 

 National Forest now produces 2-year-old ponderosa pine seedlings 

 at a total cost of about $3 per thousand trees. 



Several examples of research findings may be given as an indication 

 of the progress that can be made in solving those nursery problems 

 that still confront the forester. Delayed germination of western 

 white pine seed formerly handicapped nursery output by causing 

 seed to germinate so late in the season that heavy mortality resulted 

 due to heat killing during the summer, and produced seedlings of very 

 uneven size at the time of transplanting. Experiments carried on 

 at the Sa venae Nursery (Montana) of the Forest Service have over- 

 come this problem by demonstrating the feasibility of fall sowing 

 of western white pine seed. 



Many valuable species produce good crops of seed only at intervals 

 of several years. Seed years in longleaf pine are usually so far apart, 

 and the seed has deteriorated so rapidly under previous methods of 

 storage, that there are periodic dearths of seed in all localities. If 

 longleaf pine production in a nursery was to be sustained, this meant 

 that it was often necessary to obtain seed from some distant point, 

 with the attendant dangers of its being unsuited to the new locality. 

 It has been found that longleaf pine seed if dried promptly after 

 extraction and stored at a temperature between 34 and 40 F. will 

 keep for 2 or 3 years, with no serious loss of vitality. 



Much research needs to be carried on to insure the most economical 

 and satisfactory production of nursery stock on a large scale but 

 progress to date along this line is encouraging. 



Planting methods have been the object of much experimentation. 

 While cheap and successful methods have been worked out for some 

 situations, the cost of planting is still high on many sites. It should 



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