REPORT ON FORESTS. 105 



humus, which finally is intimately mixed with the mineral soil. 

 In New Jersey the upper layer of litter, which becomes exceed- 

 ingly dry and burns rapidly, is generally looked upon as a posi- 

 tive evil, a danger to the welfare of the forest. This has led 

 many owners of forest property to burn their land every spring- 

 before the dry season commences, and thus destroy the litter. 

 Fires are in this way prevented from burning over the land later 

 in the season and injuring the timber. Many people believe 

 that this is the only way to protect their land from fire. As 

 long as there is no organized fire service, this annual burning of 

 the land and the consequent deterioration of the forest is cer- 

 tainly better than the destruction of valuable timber. If, how- 

 ever, the danger from forest fires can be reduced, which is shown 

 elsewhere to be entirely possible, this annual burning becomes 

 unnecessary. That it should cease is extremely desirable in 

 view of the fact that in the majority of cases it is an actual 

 injury to the forest. 



An occasional light surface-fire can do comparatively little 

 harm to the forest aside from the injury to young growth, for 

 only the upper layer of dried leaves is burned and the lower, 

 more valuable humus remains. Severe fires destroy the whole 

 of the forest floor, and a considerable number of years must pass 

 before it can be formed again. Continual burning, if it does not 

 actually destroy the layer of humus, prevents new humus from 

 forming, and what is left finally becomes disintegrated, and the 

 same result follows as though it were destroyed at once. What- 

 ever may be said of individual fires, their effect as a whole in 

 South Jersey is simply disastrous. 



On the loose, porous, sandy soil of southern New Jersey what- 

 ever tends to prevent the drying-out of the surface is valuable, 

 for without moisture in the soil all other factors are of little 

 consequence. According to German authorities, humus formed 

 under conifers is capable of holding four or five times its own 

 weight of water without losing a single drop, and it has besides 

 a remarkable power of absorbing watery vapor from the air. A 

 layer of humus is a powerful factor in preventing evaporation, 

 and in New Jersey this drying-out of the soil is one of the most 

 serious effects of the removing of the forest cover. Prof. Eber- 

 mayer, of the University of Munich, has established by actual 



