No. 7. DEPARTMENT OF AGRICULTURE. 519 



barrels of fifty-five gallons each. This is no inconsiderable amount. 



In seasons of more than average dryness an amount of vapor such 

 as the above, added each day to the atmosphere, must have a bene- 

 ficial effect upon all forms of smaller vegetation, for descending at 

 night in the form of dew, it furnishes a considerable part of the 

 moisture necessary for ordinary growth. 



It is maintained by some that the presence of large wooded areas 

 is conducive to rainfall. The investigation of this question has 

 not yet yielded satisfactory results. It is certain that the forest 

 does in no way check the volume of rainfall. It is held by many 

 that when the great volume of watery vapor rises into the atmos- 

 phere to the cloud forming strata of air, it is, under favorable con- 

 ditions, but a step to the point of complete saturation and precipi- 

 tation. 



The forest is a soil former and in this way may be of value to 

 the horticulturist. The roots bring up from the depths of the earth 

 mineral plant foods which find their way back to the surface of the 

 earth in the form of twigs and leaves, there to decay and form the 

 valuable humus or mulch, found in every protected forest. A small 

 wooded area will furnish many hundred loads of rich forest soil 

 which may be used by the horticulturist on thin or well worn soils 

 with the best results, as well as employed for the lightening, sweet- 

 ening, and general improvement of heavy soils. So well known is 

 the forest as a soil former that on the continent of Europe worn out 

 areas are planted with quick growing trees. At the end of thirty 

 years the trees are marketed and the soil is found to have regained 

 its former vigor and excellence, now ready for the intensive farming 

 which characterizes those thickly populated countries. 



In some localities vegetation suffers greatly by reason of the in- 

 tensity of storms and prevailing winds. Horticulture under these 

 conditions must of necessity suffer severely. The wind bloweth 

 where it listeth but its force can be diminished and consequent de- 

 struction of small fruits and tender vegetables decreased by the 

 planting of suitable trees to act as a wind-shield or screen. Noth- 

 ing better of the kind exists than a nearby wood heavily timbered, 

 interspersed with hemlocks, firs, and other low spreading coniferous 

 trees. It is the experience of many fruit growers that among the 

 most dangerous obstacles to their business are the violent storms 

 likely to occur at times of greatest disadvantage and without warn- 

 ing. A more generous forest planting, or an adaption of lands for 

 horticultural purposes well situated with respect to forested areas 

 could not be other than helpful. 



In localities where the soil is light, thin, and disposed to be sandy, 

 another obstacle to the art of the horticulturist is dust storms and 

 the shifting of soil by means of the wind. With the force of the 

 wind broken by the intervening forest, the dust and sand deposited 

 within, or on the windward side of the wooded land, the forest takes 

 the place of a great filter, allowing clean air to emerge and prevent- 

 ing flowers, fruit, leaves, the sensitive organs of orchard and garden 

 plants, from being choked with dust, sapping their vitality by the 

 absorption of watery juices, to their most certain injury, rendering 

 such fruit unfit for the market, and destroying hopes of profitable 

 return to the owner. 



Another benefit which, it is believed, the forest confers upon the 



