STATE HORTICULTURAL SOCIETY. 343 



show that the water supply in a forest is slower but more dura- 

 ble, equal and copious than in open, forest-covered regions. 



The forest has an influence on the flow of water above ground. 

 The moss, vegetable growth and layer of leaves aid in restrain- 

 ing and regulating the onward flow. This occurs only on the 

 mountains and in the high land. The opposite is not the case at 

 such places. Government Officer Growig has made the follow- 

 ing observations with regard to the relation of the water to the 

 moss in the forest: Five ounces of dry moss were placed under 

 water, and in the first minute they absorbed 30 ounces of the 

 water, and in the following 9 minutes li more ounces. A quan- 

 tity of moss of this sort would then contain at least 4.47 more 

 rainwater. In the mountains the quantity would be 10 m.m., 

 not including what would be retained between the stems and 

 twigs of the moss by capillary action. On account of this a 

 forest thus covered would have a water strata of 2-3 c. m. in a 

 short time. 



A forest a quarter of a mile long can retain from 1,000,000 to 

 1,500,000 c.b.m. of water. The author remarks the following: 

 In many instances a difference of 20-30 c. b. m. in the water flow 

 in a second on the surftice for a quarter of a mile, will decide 

 whether high water will be injurious or not. The treeless sur- 

 face will yield from 20-30 c. b. m. fifteen hours sooner than the 

 one covered with forest. If one remembers that the floods are 

 mostly of short duration, then it will be discovered that the 

 water stratain a moss-covered declivity has an important function 

 to perform. Where the forestshould be naturally,it should be pre- 

 served and cared for. The height which would otherwise be un- 

 productive, the steep declivity will be of benefit to the water 

 surface. 



There are undisputably proven cases on record where the 

 removing of the forest or the planting of trees has an effect 

 on the water supply. They are somewhat scarce. They are ob- 

 servable only occasionally. In France and in Switzerland there 

 are such examples. In consequence of the cutting away of the 

 forests the flow of water became so irregular that the factories had 

 to remain idle during a large part of the year. As soon, however, 

 as the forests grew, this condition was changed. Just how much 

 influence the forests have upon the general health has not been 

 shown. It is desirable that the mountains and slopes be covered 

 with forests on account of their effect on the climate. The 

 surface should be used for general culture. This would nat- 



