174 OHIO EXPERIMENT STATION: BULLETIN 332 



scarcity of insect-eating native birds. A census of the bird popu- 

 lation of country and city shows a tremendous difference in favor 

 of the former, with regard to both the number and the usefulness 

 of the species involved. This condition is due, no doubt, in part 

 to the lack of a natural habitat in the city and its environs, but 

 partly due to thoughtless persecution. The latter, however, is 

 rapidly decreasing from year to year, both on account of wise, firm 

 legislation and on account of the changed attitude in the hearts of 

 the people toward our natural friends. Unquestionably, the pres- 

 ence of the Enghsh sparrow in the cities has had a strong influence 

 toward the practical elimination of our native insectivorous birds 

 and the attending prevalence of the insect pests, since the sparrow 

 is not a bird of pronounced insectivorous habits and, in addition, 

 is notorious in its behavior toward other species. In justice, how- 

 ever, it must be said that there are some indications that the spar- 

 row may be acquiring an appetite for insects, since the records of 

 observed instances where this bird has actually captured and eaten 

 insects are becoming increasingly abundant from year to year. 



Efforts to attract the native birds and win them back to the 

 city by offering food and shelter are well worthy of consideration. 

 Certainly such efforts will be repaid manyfold in the currency of 

 countless insects destroyed and at the same time will yield a harvest 

 of pleasure not previously imagined. 



INSECT CONTROL POSSIBLE UNDER CITY CONDITIONS 



With but a few exceptions, the control of injurious insect pests 

 under city conditions is possible and at the same time highly prac- 

 ticable. The tree growing in the city, especially in the residence 

 and park or boulevard districts, is valued far above the actual worth 

 of the lumber contained, by reason of its influence on nearby 

 property values, and hence its protection from the work of its 

 natural enemies is a matter of business economy. This, of course, 

 involves the expenditure of funds, in many cases in insignificant 

 amounts as compared with the returns secured. In other instances 

 the outlay may be considerable but still not prohibitive when the 

 real value of the tree is taken into consideration. The element of 

 time is the greatest factor involved in the production of a good tree. 

 The expenditure of a few dollars at a critical period may be the 

 means of saving a splendid specimen, which might require a century 

 to replace. 



In a very few instances, however, particularly with outbreaks 

 of some of the boring insects, the successful execution of control 

 measures is quite impossible. 



