46 FORESTATION, SAND HILLS NEBRASKA AND KANSAS. 



forests as early as 1901. 1 Since 1909 it has increased very rapidly 

 at Halsey, doing a great deal of damage to jack pine, and to a less 

 extent to yellow pine. The larvae of this moth bore into the young 

 succulent shoots at the ends of the branches, hollowing them out for a 

 distance of from 2 to 6 inches and usually causing the death of the 

 shoot as far back from the tip as the boring goes. New growth 

 is usually made at once from buds below the affected tip, but the 

 natural leader on the main stem or side branch of the tree is 

 destroyed, and with it the possibility of symmetrical growth. On 

 those trees which have been attacked for two or three years such a 

 large number of shoots have been formed to take the places of those 

 destroyed that a " witch broom" is made. Should the pest become 

 less abundant soon, the damage so far done will not work any per- 

 manent injury to the trees. Dr. A. D. Hopkins, of the Bureau of 

 Entomology, United States Department of Agriculture, is authority 

 for the statement that observations on this insect in the District of 

 Columbia and vicinity since 1879 indicate that continued damage is 

 prevented by natural enemies, and that only at comparatively long 

 intervals is it very abundant and injurious. Two parasites have 

 been found to attack this insect in the Nebraska plantation. 



The sawfly 2 which is destroying pine in the Pine Ridge has not 

 yet appeared at Halsey. 



BIRDS AND RODENTS. 



Pocket gophers are probably the next most damaging enemies of 

 the young forest and kill a good many trees. Most of the damage 

 is done immediately after planting, since the stirring up of the soil 

 seems to attract these animals. The gophers are everywhere present, 

 and have done some damage in each plantation each year, taking 

 trees of as great height as 6 feet. The poisoning of these animals is 

 not impossible, but it is slow and expensive work. 



Sharp-tailed grouse and quail nip the buds, and rabbits cut off 

 the tops of young trees. The harm from these injuries is that they 

 retard growth, though in the Kansas sand hills so many trees were 

 killed outright by rabbits in 1909-10 that it was necessary to pro- 

 tect the small planting area by a rabbit-proof fence. In this case 

 the bark of yellow pine was taken off almost completely. It becomes 

 less attractive after the trees have been out one season. Corsican 

 pine was started in the Garden City nursery in 1910, principally 

 because it was immune from rabbit damage. 



i Forest Belts of Western Kansas and Nebraska, Bulletin 66, Forest Service, U. S. Dept. of Agriculture. 

 1901. 



a A New Sawfly Enemy of the Bull-pine in Nebraska, M. H. Swenk, 24th Annual Report, Nebr. Agr. 

 Experiment Station. 



