2 THE A U'DIUCB ON | "BeU sie eee 
Service and the Fish and Wildlife Service to send observers. Tests were 
to range from 0.2 to 5 pounds of DDT per acre. But recent tests by the 
Bureau of Entomology and Plant Quarantine and military areas had 
shown lower rates were effective. Last minute plans were changed to 
0.5 pound per acre, and these were held uniformly for the August and 
September sprayings. In October, due to weather conditions and changes 
in plane control, the application was far from uniform. 
Objectives were to note by extensive observations the effect of DDT on 
fish and wildlife, including birds, mammals, reptiles, amphibians, fish and 
crustacea. Populations were noted before and after each of three spray- 
ings, and any dead or affected individuals recorded. 
DESCRIPTION OF THE SPRAYED AREAS 
Now that the war is over, a more detailed description of the area can 
be given. The Savanna Ordnance Depot is about 12 miles long and 3 miles 
wide, including some upland consisting of rolling prairie on which the 
ammunition dump is located. These upland areas were not sprayed 
except in the immediate vicinity of headquarters. The sprayed portion 
can logically be divided into three areas, one containing the flood plain 
cf the Mississippi River below the Bellevue Dam, a large island, and the 
headquarters area, which included the Apple River for a mile above its 
mouth, covering in all about 4,000 acres. The lowland area was composed 
of mixed old-age hardwoods: chiefly hard maple, ash, elm, birch, willow, 
pin oak, and swamp cottonwood. Since 1918, the entire area has been 
closed to hunting, and it might be said that all wildlife has had total 
protection for 27 years. There is little undergrowth and but a few shrubs 
due to the closed canopy and the seasonal fluctuations in the Mississippi 
pool of several feet. A common interior small pond is often in shade, 
although some are fringed with buttonbush. Most of the hardwoods are 
past their prime, and as a result, the decayed trees provide in excess of 
10 den trees per acre. This, perhaps, partially accounts for the astonish- 
ingly high raccoon population. As the pool drawdown is rather sharp 
throughout the summer, bottom lands are covered with new layers of silt, 
permitting little vegetation. Occasionally where trees have died from ex- 
cessive floods, young hardwoods prevail. Buttonbush and a ground covering 
of grasses, juncus, asters, hibiscous, cardinal-fiower, and other miscellaneous 
vegetation grow luxuriantly. Under the canopy of mature hardwoods 
poison ivy persists in tangled low thickets. Bordering the large ponds and 
waterways are mixtures of ash, river elm, cottonwood, willows, and tangles 
of wild grape. 
The open water area above the Bellevue Dam near the Illinois shore 
supports several hundred acres of the American lotus (Nelumbo penta- 
petala), a favorite feeding place for waterfowl in October. With the . 
exception of a good pin oak mast crop, a few grapes and lotus seeds 
(Yonker nuts), the area did not yield a great deal in seeds, nuts, or fruits, 
for late summer and fall use by wildlife. Most of the water areas were 
devoid of pondweeds and other vegetation due to the fluctuations in water 
levels, and without doubt carp and other fish were factors in causing so 
