February, '17] DAVIS: LACHNOSTERNA FOOD VALUES 43 



age one gram each and the beetles sUghtly less, so that each infested 

 acre contains approximateh' 235 pounds of grubs which have a food 

 value of more than $3, that is, $30 for ten acres, enough to pay for 

 fencing the field with hog-tight wire. In addition to the value of the 

 grubs as hog feed the value of the manure produced should also be 

 considered. In his bulletin, "The Growing and Fattening of Hogs 

 in the Dry Lot and on Forage Crops, ''^ Prof. E. S. Good quotes 

 Dr. H. S. Grindley as authority for the information that 85 per cent 

 of the fertilizing constituents taken in by hogs as food is eliminated in 

 the urine and feces for the entire life of the animal, being greater for 

 mature individuals. In other words, 8J pounds of nitrogen is given 

 off in the manure for each 10 pounds taken in as food and approxi- 

 mately 3.56 pounds of nitrogen alone would be given off in the manure 

 produced by grubs eaten from one acre of ground, or 4.38 pounds if 

 beetles were eaten. 



To further illustrate the fertilizer value of the grubs it may be noted 

 that the nitrogen content contained in the protein is 1.78 per cent 

 of the entire analysis in the case of the grubs and 3.22 per cent in the 

 case of the beetles and in addition the ash is heavy in phosphoric acid 

 although the exact amount has not been ascertained. 



Three objections have been raised to the use of hogs in grub-infested 

 ground, especially in the case of pastures, namely, lack of hog-tight 

 fences, rooting up of pasture land, and possible infestation with the 

 giant thorn-headed worm, an intestinal worm affecting hogs. The 

 first objection has already been answered. Observations indicate that 

 an infested pasture, although badly overturned by rooting hogs, re- 

 seeds itself the following season with no ill effect other than a roughing 

 of the surface which is of little significance. The last objection rela- 

 tive to possible infestation with the giant thorn-headed worm {Gi- 

 gantorhynchus hirudinaceus = Echinorhynchus gigas) is of considerable 

 importance. The white grub is an intermediate host of this worm 

 which seems capable of entering hogs only by being taken into the 

 bod}^ with grubs eaten. However, as a rule, no trouble will result 

 from these worms if hogs which have never been pastured are used in 

 fields which have not been previously pastured with hogs within three 

 years. Care should be taken to prevent brood sows from running in 

 fields likely to contain grubs infested with thorn-headed worms, that 

 is in fields which have not been hog-pastured the previous season or 

 two, but hogs being fed for market, according to our observations, can, 

 with possible exceptions of very young pigs, be pastured with less 

 regard for the past history of the field since they are usually marketed 

 before the effect of the worms, if any are present, become harmful. 



1 Bui. Ky. Agric. Exp. Sta. Xo. 175, Apr. 1915, p. 332. 



