132 Hedges and Screens : Shelter-Belts. 



get in among the dry materials that lodge in a hedge, will be sure to 

 kill it, and the strictest care should be taken to prevent this accident. 



533. In very poor soil, a trench may be dug along the line of an 

 intended hedge, and filled in with the more fertile soil of the adja- 

 cent surface, or elsewhere. It should be heaped above the former 

 level, to allow for settling. 



Shelter-Belts. 



534. As their name implies, these are belts of woodland, primarily 

 intended to protect the fields or places adjacent to them from the 

 winds, and to equalize to some extent the temperature and humidity 

 of a country, by mitigating the extremes of heat and cold, and by 

 lessening the effects of drouth. They are of special benefit to fruit 

 culture, and when planted around an orchard, in a dry climate, 

 they tend to maintain a uniform and increased yield, the effect of 

 which is often made apparent by comparisons with the barrenness 

 and failure of orchards not thus protected. 



535. Their effect in diminishing the damages that occasionally 

 happen from grasshoppers, and other insects, is well proved ; and 

 by favoring the breeding of insectivorous birds, they further pro- 

 mote the destruction of the enemies of our fruit and field crops. 



536. Their direct influence upon pasturage and meadows is seen 

 in the fresh green color of the herbage, and its perceptibly larger 

 growth. They have been known to double the yield of grain in 

 fields surrounded by them, by preventing injuries to which open 

 and naked fields are exposed. 



537. In snowy countries, an important effect is secured in their 

 preventing the drifting of snows, which cover the surface longer 

 and melt away more slowly. The water will settle into the ground, 

 and the soil remain moist for a longer period than in broad open 

 fields. Their immediate shelter to gardens, buildings, and stock 

 yards, and the cheerful and pleasant aspect that they impart to a 

 country, are obvious. 



538. A shelter-belt should be planted more closely than would be 

 advantageous in a forest, and as the outside gets more air and light, 

 the trees along the borders will be more thrifty than those in the in- 

 terior. It should be not less than four rods in width, but ten rods 

 would be better. For full benefit, they should not be more than a 

 quarter of a mile apart 



