PKOTECTION FKOM THE LOCUST BORER. 5 
old waste land, the soil of which has been enriched by a thick bed of 
humus beneath the trees. 
Another group (PL I, fig. 2) near by contains about 30 trees similar 
in respect to size and conditions. These have seeded the surrounding- 
soil so that a large clump is formed of dense growth, the outermost 
being some 6 to 8 feet high. None of these trees have been injured 
by the borer. A third group (PL II, fig. 1), forming a small oval 
clump, contains 38 trees from 2 to 4 inches in diameter and 15 feet 
high. They were closely set, averaging 4 feet apart. A few sassa- 
fras were intermixed. In July, 1918, not one of these trees contained 
a borer. August 20, 1918, the plot was thinned, all branches trimmed 
to 8 or 10 feet, arid all weeds and briers removed. The trees were 
closely watched and many adults were observed ovipositing on them 
during September. 1 Adults were likewise observed on the isolated 
trees near by, but none in the dense plats described above. 
6. A fence row opposite the eastern field station at Falls Church, 
Va., is densely matted with wild cherry, honeysuckle, and goldenrod 
along the sides. Through this grow a dozen locusts (PL II, -fig. 2) 
2 to 4 inches in diameter. None of these trees were infested on or 
previous to August 15, 1918, on which date all the surrounding 
growth was cleared from four trees. During September adults were 
observed ovipositing on these four. Many such fence rows exist 
wherever locust is grown and explain why so little trouble is experi- 
enced on the average farm. 
7. Along the south bank of the Potomac River between Difficult 
Run and Scotts Run many locusts are growing on the wooded slope. 
This stand is a hardwood mixture composed chiefly of oak, chest- 
nut, hickory, tulip tree, basswood, and butternut. All the locusts 
are tall, straight poles, reaching to the top of the stand, the trees 
averaging from 6 to 18 inches in diameter. All show a thrifty condi- 
tion of growth and no borer defects. A low meadow, sometimes cul- 
tivated but now pastured, lies between this river terrace and the 
water. A few occasional locusts grow here, nearly all of which are 
infested and badly deformed. No goldenrod occurs in the meadow, 
and the adult beetles were observed to feed on several species of 
Eupatorium. 
PLANTATIONS ALONG THE PENNSYLVANIA EAILROAD. 
From the office of the forester of the Pennsylvania Railroad rec- 
ords have been secured of 42 plantations, comprising nearly 2,000 
acres, on which over 1,000,000 trees were planted. These trees were 
about 2 years old when set out and usually were spaced 8 by 8 or 8 by 
10 feet. Many of these tracts were personally examined by the 
writer, accompanied by Mr. I. T. Worthley, assistant forester. The 
history of each plantation was ascertained as accurately as possible. 
1 Examination of this plot on Apr. 8, 1919, showed an average of 15 borers per tree. 
