differences in concentrations of elements in soils were 
not directly proportional to the levels in either plant 
seeds or pheasant feathers. 
DISCUSSION 
The amounts and rates of flow of minerals through 
the ecosystem, i.e., from soils to plants to animals and 
eventually back to soils, have profound and _ far- 
reaching effects on all living organisms. In the present 
study, sodium, potassium, calcium, and magnesium 
were not, for the most part, incorporated into plant 
seeds and pheasant feathers in the same proportions 
that they occurred in soils. For example, significant 
differences existed in the amounts of potassium in 
foxtail seeds and of magnesium in corn between the 
Sibley and Neoga areas. Yet correlation analyses indi- 
cated that a significant inverse relationship existed 
between the concentrations of potassium in soil and in 
foxtail seeds (r= — 0.445, 18 df) and between the con- 
centrations of magnesium in soil and in corn (r= 
— 0.618, 18 df). Clearly the flow of elements through 
the environmental complex was not straightforward. 
As the uptake and use of elements by plants and ani- 
mals are influenced by many factors, this finding was 
understandable. Interactions among elements are par- 
ticularly effective in altering translocation and storage 
of minerals in plants and animals (Schiitte 1964). 
The role of calcium is central to the many consid- 
erations of ion uptake by plants (Emmert 1961). 
Calcium is reported to antagonize the uptake of man- 
ganese, potassium, iron, boron, zinc, and magnesium 
in some plant structures (Schtitte 1964:41). Corre- 
spondingly, we found the concentrations of magne- 
sium in corn were inversely and significantly corre- 
lated with the amounts of calcium in this grain (r= 
— 0.623, 18 df). Yet we found no significant correla- 
tions between soil calcium and the subsequent uptake 
of potassium by foxtail seed (r—0.041, 18 df) or of 
magnesium by corn (r=0.306, 18 df). However, these 
relationships are tempered by the fact that our deter- 
minations were for total soil calcium and not for plant- 
available calcium. 
The low levels of calcium in corn, the staple diet of 
the pheasant, are noteworthy. If pheasants are to ob- 
tain a sufficient level of calcium—at least the minimum 
dietary requirement of 1.2 percent as indicated by Dale 
and DeWitt (1958 In Greeley 1962:186) and Scott 
et al. (1958:1421)—they must obtain it from calcareous 
grit. To illustrate, if a pheasant consumes 35 g of corn 
(R. F. Labisky & W. L. Anderson unpublished) con- 
taining 35 ppm of calcium per day, its dietary intake 
of calcium is only 0.0035 percent. To attain the 1.2 
percent level, the pheasant must then ingest daily, and 
totally utilize, 1.04 g of limestone containing 40 per- 
cent calcium. In this case, the limestone grit consti- 
tutes 99 percent of the pheasant’s calcium intake. 
The differences detected in the concentrations of 
potassium, calcium, and magnesium in the soils of the 
Neoga and Sibley areas (Table 1) illustrate, some- 
what axiomatically, that older (Illinoian) glacial drift 
is relatively poor in three, and probably several more, 
important inorganic nutrients. These findings sup- 
port the contention that a deficiency of calcium, and 
perhaps of other minerals, may limit the distribution of 
pheasants in many areas in the eastern United States. 
If, however, pheasants on the Neoga area were suffer- 
ing from insufficient levels of potassium, calcium, or 
magnesium, the insufficiencies were not expressed in 
the mineral composition of their feathers (Table 1). 
Inasmuch as Burns et al. (1953:327) reported that 
a wide disparity in the ratio of sodium to potassium 
was toxic to domestic chicks (Gallus gallus), the high 
ratios of sodium to potassium in soils, foxtail, and 
pheasant feathers from Neoga suggest that a nutri- 
tional imbalance may exist on the Illinoian drift (Table 
2). In this particular case, the disparity in the sodium: 
potassium ratio in soils from Neoga and Sibley (0.42 
versus 0.26) was similar to that reflected by the feath- 
ers from the respective areas (2.90 versus 1.58). Al- 
though calcium:magnesium ratios differed  signifi- 
cantly for soils and corn from the two areas, no differ- 
ences were found for the feathers. Little is known 
of how the relative levels of these elements affect the 
uptake and metabolism of other minerals by the pheas- 
ant. 
None of the elemental differences, as such, found 
in the soils, plant seeds, or pheasant feathers from the 
pheasant-poor area on Illinoian drift (Neoga) and 
from the pheasant-rich area in Wisconsinan drift (Sib- 
ley) is satisfactory—with our present knowledge of the 
mineral needs of pheasants—to explain the magnitude 
of difference in population levels between the two 
areas. Nevertheless, differences did exist between 
the areas in concentrations of sodium, potassium, cal- 
cium, and magnesium in soils; of magnesium in corn; 
of potassium in foxtail; and of sodium, potassium, and 
magnesium in pheasant feathers. These findings, to 
our knowledge, represent the first documentation of 
clear-cut elemental differences in both birds and en- 
vironment between areas of contrasting pheasant 
abundance. 
SUMMARY 
Concentrations of four essential elements—sodium, 
potassium, calcium, and magnesium—were measured 
in soils, plant seeds (corn and Chinese foxtail), and 
pheasant feathers from two areas of contrasting pheas- 
ant abundance in Hlinois. The low-density pheasant 
population was located on the geologically older IIli- 
noian glacial drift and the high-density population on 
the younger Wisconsinan drift. Potassium, calcium, 
and magnesium were less abundant, and sodium was 
more abundant, in Illinoian drift soils than in Wiscon- 
sinan drift soils. Magnesium was more abundant in 
corn, and potassium was more abundant in foxtail on 
the Illinoian drift. And higher concentrations of so- 
dium, potassium, and magnesium were found in feath- 
7 
