SILVEK FOX FARMING. 9 
surface is to be avoided, but a subsoil of clay or hardpan is an advan- 
tage, as foxes will not dig ground hard enough to require a pick to 
break it up. Gravel affords excellent drainage, but foxes burrow 
deeply in it and thus are difficult to manage, even though they may 
not escape. 
INCLOSURES. 
A model fox ranch has three kinds of in closures: Dens, where the 
animals are sheltered and in which the young are born; yards or runs, 
where they may have sunshine and shade and sufficient exercise to 
keep them in good health; and a guard fence surrounding the entire 
ranch, for the double purpose of preventing intrusion from without 
and escape from within. 
DENS. 
The walls of a fox den should exclude moisture, deaden sounds, and 
protect the occupants from extremes of heat and cold. During the 
Fig. 4.— Horizontal longitudinal section of barrel den. 
breeding season, when foxes are unusually nervous, and when the cubs 
can not withstand exposure, these features are particularly impor- 
tant. Provision should also be made for ventilation without admit- 
ting light or drafts. The barrel den shown in figures 3 to 6 is 
merely a clean barrel, having a smooth interior, surrounded by dry 
sawdust, within a wooden box. In one head of the barrel is an 
entrance hole 8 inches wide and 10 inches high. A similar opening 
is made in the upper side for inspection, cleaning, and ventilating. 
Above the barrel a screen door is hinged to preclude escape when 
the cover is raised. A sheet of burlap tacked to one side of the screen- 
door frame and spread over the netting when the covers are raised for 
ventilation will keep out air currents and light. At the entrance hole 
is an elbowed spout, 2\ feet in the shorter arm and 6 feet in the longer. 
5238°— Bull. 301—15 2 
