FOOD OP SAPSUCKERS. 95 



trees had thus been killed. In prairie countries, where trees are a deficiency and 

 their cultivation both important and attended with difficulty, these birds prove a 

 great pest, and in a few hours may destroy the labor of many years. 1 



Whether or not the downy and other woodpeckers seek sap, it is 

 beyond question that they are not important consumers of cambium, 

 since on the average much less than 1 per cent of this substance has 

 been found in the stomach contents of any other woodpecker than 

 the true sapsuckers (SpJiyrapicus). 2 It is the loss of cambium rather 

 than of sap that breaks down the vigor of the trees and is responsible 

 for defects in the wood, and to the sapsuckers, which consume cam- 

 bium to an average extent of 13.8 per cent of their annual food, 



Fig. 41.— Pileated woodpecker. Not a sapsucker. Entire lower parts black. 



must be attributed most if not all serious injuries to trees due to the 

 destruction of cambium by woodpeckers. 



FOOD OF SAPSUCKERS. 



About four-fifths of the insect food of the three species of sap- 

 suckers consists of ants, the eating of which may be reckoned slightly 

 in the birds' favor. The remainder of the food is made up of beetles, 

 wasps, and a great variety of other insects, including, however, prac- 

 tically no wood-boring larvae or other special enemies of trees. The 

 birds' vegetable food can not be cited in their behalf, as it consists 

 almost entirely of wild fruits, which are of no importance, and of 



» Baird, Brewer, and Ridgway, History of N. A. Birds, Land Birds, II, 542, 1874. 



2 A mere glance at the figures (3 and 4) of the tongues of the yellow-bellied sapsucker and the downy 

 woodpecker must convince anyone that these birds are adapted to the utilization of entirely different food 

 supplies. 



