72 
FLORIDA STATE HORTICULTURAL SOCIETY 
wasteful of fuel in that they cannot be 
readily extinguished. The fire will be 
either too high or too low, as a general 
thing. It has been found by experience 
that a large number of small fires, well 
distributed through the grove, is more effi¬ 
cient than the same amount of heat gen¬ 
erated by fewer large fires; but this is 
hard to manage when wood is used for 
fuel. The fire is apt to be too high when 
first built, and gradually burns down and 
will allow ithe 'temperature to get too 
low for safety. 
Secondly, coal: This is practically out 
of the question here on account of the 
cost. In some of the coal-producing sec¬ 
tions, coal is burned with fairly good re¬ 
sults. 
Thirdly, oil: There are a great many 
different grades of oil, ranging from Mex¬ 
ican crude, which has a high percentage 
of asphaltum, down through the lighter 
oils to distillate and kerosene. In the use 
of oil it is necessary to have a can of 
some type to hold it. There are at pres¬ 
ent on the market a great variety of cans, 
or as they are popularly called—smudge 
pots or heaters. They range all the way 
from the small, round lard pail type, hold¬ 
ing about a gallon, to the large reser¬ 
voir heaters with drafts and chimneys, 
having a capacity of n 1-2 gallons and 
costing from 20c to $1.55' each. In choos¬ 
ing a type of heater, the first considera¬ 
tion should be the grade of oil available. 
Kerosene may be burned in an open pail 
with a very little ill effect from soot, but 
the heavier oils, if burned in this type of 
heater, give off a dense sooty smoke, 
which, if much firing is done, will greatly 
damage the fruit. 
There was considerable loss in Cali¬ 
fornia from sooting fruit a year ago last 
winter. It does not really hurt the fruit, 
but it is a greasy, black smut that is very 
hard to wash off and hurts the sale of the 
fruit very much. 
There are, however, several different 
types of smudge pots which generate gas 
from the oil, and by the use of drafts, 
burn this gas practically clean, even from 
the heaviest oils. There will be some little 
smoke even from some of the so-called 
smokeless heaters, but if it is of a bluish 
or hazy nature, no ill effect on fruit or 
trees will be felt from it. There are heat¬ 
ers now which generate gas by a draft of 
air down onto the surface of the oil 
through the cover of the pot; also by run¬ 
ning the oil through a coil of pipe which 
is heated from the flame itself; and one 
heater which I know generates gas by 
allowing the oil to drip through a recep¬ 
tacle containing coke. This last heater 
can be fed direct by pipe lines from tanks 
or reservoirs located in the grove, and 
operated by valves so that they can be 
turned out very quickly if the temperature 
rises above the danger point. This, I con¬ 
sider an important factor for, at the pres¬ 
ent price of oil, every gallon that can be 
saved is an item to be considered. With 
this system also there would be no loss of 
oil from spilling when taking up the heat¬ 
ers in the spring or putting them out in 
the fall. In one grove this year a grower 
reported the loss of 8,000 gallons of oil 
in filling and emptying heaters. The 
originator of this heater is a member of 
our society and has used these in a small 
patch of grove twice this last winter, and 
he told me they worked remarkably well. 
I have seen them burn and think they 
are fully as efficient as any. 
