SYLVICULTURE. 



stones, in order to allow of proper seed planting and in order to 

 facilitate the digging of the plants. 



II. Exposure: The best exposure is a gentle northwest slope. 

 The bottom of a valley is too frosty in spring. Southwest and 

 southeast slopes are subject to rapid atmospheric changes. East- 

 ern aspects invite damage by frost. 



III. Proximity to water and possibility of irrigation. 



IV. Accessibility and distance from ranger's house. 



D. Fertilizing: Stationary forest gardens require continuous 

 fertilizing. Ci'ops of seedlings exhaust the soil like grain. 



The following table exhibits, in pounds per acre, the amounts 

 of fertilizing matter annually consumed by Pine seedlings. Pine 

 poles and crops of rye. 



Yellow pine Yellow pine Crop of 

 Fertilizing matter. one year old. eighty years old. rye. 



Phosphoric acid 9.8 lbs. 1.7 lbs. 16.7 lbs. 



Potash 20.7 lbs. 2.8 lbs. 24.2 lbs. 



Calcium 17.2 lbs. lO.I lbs. 9.7 lbs. 



Magnesia 3.0 lbs. 2.0 lbs. 4.2 lbs. 



Sulphuric acid . . : 0.0 lbs. 0.3 lbs. 1 . 1 lbs. 



The following fertilizers are used in forest gardens: 



I. Animal manure, which is considered best. Cattle manure 

 is preferred to horse manure; on clay soil, however, horse manure 

 is better. Heavy weeds come up from stable manure which has 

 not had time to fully decompose. 



II. Commercial fertilizers: Experiments conducted with super- 

 phosphate, bone meal and so on have failed to yield conclusive 

 results. The best kalium fertilizer seems to be kainit (kalium 

 chloride) ; the best nitrogen fertilizer is saltpeter. 



After Von Schroeder, the following quantities of phosphates, 

 potash and nitrates are needed to raise 4,000,000 plants on an 

 acre of nursery: 



520 lbs. kainit. 



60 lbs. superphosphate. 



320 lbs. whale guano. 



III. Humus, the natural forest manure, is the cheapest fer- 

 tilizer obtainable in the woods. Humus of Pines mixed with that 

 of broad-leaved species is best. Humus just one year old is said 

 to be richest in bacilli favoi-able to tree growth, and to be devoid 

 of filiform fvmgi disastrous to plants. 



The weeds removed from nurseries furnish, through their de- 

 composition, a valuable humus. 



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