The subsoiler attachments are standard for any tractor 
with a hydraulic three-point hitch. The adjustable third link 
that is fastened to the top of the subsoiler and to the middle of 
the tractor must be 30-3/8 inches long at midadjustment. A stand- 
ard Ford link has to be lengthened about five inches to be usable. 
Figure 3 is a detailed drawing of the machine. 

Costs 
The above parts cost $291.13, and labor and additional 
materials amounted to $178.81. The total cost of a "burrow-builder" 
was $469.94 but this could be reduced to approximately $450.00 if a 
number of machines were to be made. This price was quoted by 
Schneidmiller Industries, 334 East Mountain Avenue, Fort Collins, 
Colorado. 
Operation 
The “burrow-builder" is designed to construct an artifi- 
cial burrow and bait it with poison baits in one operation. For 
effective use in pocket gopher control, a number of adjustments 
must be made. The depth of gopher runways first must be deter- 
mined by measuring existing burrows, and the machine then must be 
set at the desired depth. A few short trial runs should be made 
and the top link adjusted so that the machine rides the ground 
with the wheels barely packing the soil. If the "bite" of the 
torpedo is too great, the wheels start dragging dirt; if the 
"bite" is too little, the torpedo will not stay in the ground. 
The condition of the soil has to be such that a good 
burrow can be made. This usually means that there is enough 
moisture in the soil to make it firm into a pack when squeezed in 
the hand. 
Pocket gophers inhabit areas from sea level to the tops 
of our highest western mountains, and are found in both agricul- 
tural and rangelands. The "burrow-builder" can be used for control 
of gophers in any area where soil conditions and the physical 
aspect of the land make it possible to drive over the area with a 
tractor and construct a good artificial burrow. 
In order to make a good burrow it is necessary that the 
soil is moist. In the arid West this condition can usually be 
found in the spring or fall of the year. 
