Vol. 10, No. 10 
Page 3 
Vegetative analyses of the seeded and nonseeded portions of the standing 
corn were made during late July and early August. Vegetation was sampled 
with a 1/16-square-meter quadrat. A total of 142 quadrat samples were taken 
in the seeded portion, and I 36 samples were taken in the nonseeded portion. 
Plant species were identified, and the percent top cover of each species 
present and percent bare ground were estimated. 
Averages of 16 and 25 percent bare ground occurred in the seeded and 
nonseeded portions, respectively. The five most frequently occurring plant 
species in the seeded portion were: rough buttonweea ( Diodia teres ), 
Trifolium repens , golden rod ( Soli dago spp.), tickle grass ( Agrostis hyemalis) , 
and Canadian St. John's-wort ( Hypericum canadense ). The five most frequently 
occurring plants in the nonseeded portion were: Diouia teres , Solidago spp., 
wild bean ( Strophosty1es spp.), A grostis h yema1is , and foxtail ( Setaria spp.). 
Thus, seeding the two clovers reduced the amount of bare ground, essential 
in good quail habitat, and replaced native legumes, Stroohosty1es spp., with 
a cultivated one^ Trifolium repens .. 
5. Responses of Prairie Chickens to Habitat Hanipu1 ation R. L. Westemeier 
Since I 963 , on the Bogota Study Area, 43 prairie chicken nests have 
been found in 704 acres of grassland dominated by redtop--a density of 6.1 
nests per 100 acres. By categorizing this acreage into five classes ranging 
from 1 to 4 years of age, with fields over 4 years of age considered as old 
sod, respective densities of 2.0, 14.0, 8 . 3 , 5-6, and 4.3 (nests per 100 
acres) were revealed. Thus, 2nd-year redtop, with a density of 14.0 nests 
per 100 acres, has a density 3*3 times greater than the density for old sod. 
These c'ata help explain the declining use of the Yeatter and McGraw sanctuaries 
by nesting prairie chickens, as described previously (Monthly Wildlife 
Research Letter 10(9):2—3)- The nesting cover on these sanctuaries in 1967 
was composed of redtop stands either 1 year or 5 or more years of age. 
Another factor that appears to be important to nesting hens is proximity 
to field edge. Seventy-three percent of 40 nests found on the Yeatter, 
McGraw, and Donnelley sanctuaries since 1 963 have been within 50 yards of the 
nearest field edge. 
The oldest sanctuaries at Bogota have either been mowed annually for 
weed control or combined for redtop seed. Both practices result in buildups 
of vegetative duff on the ground. Apparently, prairie chicxens find the 
excessive layers of residual cover undesirable for nesting arid brood-rearing. 
More subtle ecological changes than buildup of duff may also be responsible 
for the declining use by nesting hens of progressively older stands of redtop. 
Therefore it seems prudent to use a variety of techniques to maintain the 
attractiveness of the sanctuaries to breeding prairie chickens. Such tech¬ 
niques might include using a variety of grasses and legumes initially and 
maintaining them by prescribed burning, midsummer mowing for hay, light 
grazing, plowing and reseeding, burning and sod-seeding, and perhaps using 
strips of cultivated crops to serve as edge and fire lanes. 
