14 
FLORIDA STATE HORTICULTURAL SOCIETY 
of a gallon gasoline and from l / 2 to I pint 
of cylinder oil. 
COST OF PLOWING I ACRE 
YEAR ACRE 
Depreciation _$125.00 $ .20 
Interest on investment_ .06 
Repairs _ .08 
Fuel _ .67 
Oil and grease_ .20 
Man labor_ .70 
Total_$1.91 
Initial cost of tractor, $500. 
Life, 4 years. 
Interest at 7%. 
Fuel, 2.67 gallons gasoline. 
Four-fifths quart cylinder oil. 
Man labor at $3.50 per day. 
REPAIRS 
The yearly repair charges are very dif¬ 
ficult to obtain but according to Circular 
12 of the Extension Division they would 
be approximately one-twentieth of the ini¬ 
tial cost of the tractor the first year, one- 
twelfth of the initial cost the second year 
and one-eighth of the initial cost the third 
year. 
SELECTION 
The conditions under which farm ma¬ 
chinery must operate in Florida are un¬ 
doubtedly the most adverse of any state 
in the Union. Downpours of dust and 
sand always accompany their operation in 
the citrus grove, due to the sandy nature 
of our soils. Therefore in order to reduce 
the wear to a minimum, all of the work¬ 
ing parts of a tractor must be encased or 
the life of your tractor is very short. The 
entire transmission system must be pro¬ 
tected, steering joints, etc., should be sup¬ 
plied with large grease cups that feed 
freely. As long as grease works out of 
the bearings sand does not get into them. 
A tractor must be provided with an effi¬ 
cient air filter. If you allow air filled 
with grit to be drawn into the cylinders 
of your motor, it forms with cylinder oil 
a splendid grinding compound that soon 
cuts away the cylinder walls and you be¬ 
gin to have trouble. The moist air filters 
seem to be somewhat more efficient than 
other types in removing the dust and sand 
from the air. However, these should be 
looked after very carefully and cleaned 
real often, especially if it is very dry. 
The slippage of the wheels of a tractor 
that is bound to occur in our sandy soils 
is much more destructive than are heavy 
loads, and especially is this true of the 
bolted and riveted framed tractors. The 
unit frame tractor seems to have a decided 
advantage in this respect for the gears 
and other parts are in a fixed relationship 
to each other. The wide wheels are a ne¬ 
cessity in order to give traction. A pro¬ 
tected radiator is something that should 
receive attention from the manufacturers, 
for the circulation of air is very easily in¬ 
terrupted by leaves, etc., especially if you 
happen to be working in rank vegetation. 
This can be done by the operator by using 
a heavy ^4-inch mesh wire, mounted about 
5 inches in front of the radiator, which 
will catch the leaves and the currents of 
air to the radiator are not cut off. 
There is much more to be said on the 
question of tractor selection for grove cul¬ 
ture, but in a paper of this kind I have 
made an attempt to give only a few of the 
most important. 
