What Is the Yield of Wild Food Crops? 
N SUPPORTING COWS, pigs, horses, poultry and people it is important to 
know how much corn, oats, hay, vegetables or fruits an acre will produce.

In supporting pheasants, quail, rabbits, and song birds it is important to
know 
how much weed seed, waste grain, acorns or browse an acre will produce, how

dependable the crop is, and how much of it is utilized by wildlife. This
Station 
therefore has begun a series of measurements of wildlife food crops. 
The weeds which spring up as aftermath on small grain stubbles are an im-

portant food which the farmer converts either into game and song birds, or
into 
mice and gophers, depending on whether there is any cover to harbor birds.

What is the yield of these weedy stubbles? Seventy-five samples of one square

yard each, taken last fall by Aldo Leopold and Lyle Sowls on the Faville
Grove 
wildlife area in Jefferson county, threshed out the following quantities
of edible 
seeds: yellow and green foxtail, 50 to 450 lbs. per acre; barnyard grass,
up to 
300 lbs. per acre; lesser ragweed, 80 to 130 lbs. per acre. 
Ungrazed woodlots in southern Wisconsin support a wild bean called tick 
trefoil, which is greatly relished by quail, ruffed grouse, and pheasants.
Thirty 
samples from the University Arboretum showed yields up to 10 lbs. per acre.
It 
was discovered that there are two insects, a weevil and a moth larva, which
thin 
out the trefoil and prevent any large yield. 
Crop wastes left behind in harvesting are an important food for wildlife.
No 
satisfactory measurements of waste grain have as yet been devised, but waste

soybeans left behind at Faville Grove threshed out 150 pounds per acre. 
Rabbits Range at Least a Mile 
O   NE OF THE COMMONEST but least known species of wildlife is the ordinary

cottontail. Wisconsin hunters bagged a million cottontails last fall, but
no 
man yet knows how far an individual cottontail moves in a year. Knowledge
of 
movements is important to the landholder, whether he wishes to encourage

rabbits as a game animal or to discourage them as a threat to orchards, truck

crops, or tree plantings. 
For the past two winters the following experiment was conducted on the 
Faville Grove wildlife area: A 7-acre "pothole" which had good
cover, but which 
was surrounded by bare fields, was trapped clean of rabbits in November and

December. Each rabbit was weighed, ear-tagged, and released at a distance
of 
one mile. By watching tracks in the snow, and by continued trapping, the
return 
or "influx" of rabbits to the empty covert was observed. 
During January the covert remained empty. During February, however, 
there was a steady influx from the outside, including some of the tagged
indi.- 
viduals. One returned three times in two years. The February "shuffle"
coin- 
cided with the onset of the breeding season or "rut," and was doubtless
caused by 
mating activities. By the following fall, the pothole contained its usual
quota of 
cottontails. 
The experiment shows this covert supports 2 rabbits per acre, and that in

winter the population "stays put" until February, when the breeding
shuffle 
mixes the populations for as far as a mile.