106 N. H. AGR. EXPERIMENT STATION. [Bulletin 171 



They were in this enclosure three years in succession. The first 

 year they plowed the ground. The second year they uncovered 

 the roots of some of the trees. The third year they stripped the 

 bark from two of the trees, which caused them to die. I gave 

 them plenty of skim milk with shorts while there." 



"To my knowledge hogs in large enclosures, with plenty of 

 grass and weeds, do not strip the bark from trees." 



"I have a pasture of about four acres containing about 200 

 apple trees. Hogs have pastured there for twenty years, varying 

 in number from 5 to 30. The trees stand there to-day, thrifty 

 and vigorous, and not one that the hogs injured by stripping the 

 bark from the trees. On the other hand they have helped the 

 trees very materially by rooting the sod, by fertilizing the land, 

 and by picking up the windfall apples. My opinion is that 

 . . . hogs will bark apple trees when they are confined in a 

 small enclosure . . . but not when they have a good range." 



"We have an orchard that hogs have been kept in for the last 

 forty years, year after year. They never hurt the trees. But 

 there was plenty of grass for them, and the trees were old ones and 

 quite large. I have an idea that they would hurt young trees." 



"Have had hogs injure trees when too closely confined, and 

 grass became short. Give them plenty of run, and enough to 

 eat and drink, and they will not bark trees." 



Cows — Sheep — Poultry. Frequently, on New Hampshire 

 farms, some apple trees stand in pastures where cattle or sheep 

 range. If such trees are so located that the livestock can get at 

 all drops, and if they are in a part of the pasture frequented by 

 the stock, they may remain free of the maggot. Occasionally 

 growers permit cattle or sheep to range through planted orchards, 

 where the trees are old and large, with branches high from the 

 ground. 



Poultry are not able to dispose of infestation by the maggot 

 unless large numbers are confined to a limited area. Apparently 

 about 500 hens to an acre are required, depending on the size of 

 the trees and the relative amount of early and susceptible fruit. 

 If the trees are small the number may be less. 



It is believed, in the light of some experiments described below, 

 that a considerable part of the value of poultry may lie in their 

 ability to find and destroy pupae in the soil, and to a less extent, 

 probably, their abiUty to catch and eat newly emerging flies. 



