Lime as a Remedy for Acid Soils* 
By A* W* BIair« 
ji 
(Florida Experiment Station.) 
Mr. President^ Ladies and Gentlemen : 
Before taking up directly the relation 
O'f lime to acid soils, it may be well first, 
to refer to the amount of lime in differ¬ 
ent soils, the ease with which it is wash¬ 
ed out, etc., and discuss very briefly the 
functions of lime in agriculture. 
Calcium, which is one of the elements 
of lime, is found in the ashes of all plants, 
and some lime is found in practically all 
soils. As naturally found in soils, lime 
exists in combination with other groups 
of elements; for example as calcium 
phosphate (phosphate of lime), cal¬ 
cium carbonate (limestone), calcium 
silicate, etc.; and from these com¬ 
pounds it is dissolved by soil waters and 
taken up by plants. 
THE AMOUNT OF LIME IN SOILS. 
According to analyses made by the 
Florida Experiment Station, the aver¬ 
age amount of lime in a number of sam¬ 
ples of soil taken on the Florida East 
Coast, between Lemon City and El- 
dred, is .012 per cent., and taking the 
weight of an acre foot (the soil on one 
acre to the depth of one foot), to be 
4,000,000 pounds this would give us 
496 pounds of lime, or approximately 
1-4 ton to the acre-foot. The average 
amount of lime in samples of soil rep¬ 
resenting Orange, Hillsboro, and De- 
Soto counties is .028 per cent., which is 
equivalent to 1,120 pounds, or a little 
over 1-2 ton to the acre-foot. Many 
soils in the humid regions of the United 
States contain from .2 per cent, to .4 per 
cent, of lime and if we take the aver¬ 
age of these, .3 per cent., and the weight 
of an acre-foot of these soils as 3,500,- 
000 pounds, we find that they contain 
5 1-4 tons of lime to the acre-foot, which 
is twenty-one times the amount in the 
East Coast soils. Snyder gives the av¬ 
erage amount of lime in 200 fertile soils 
as 2.16 per cent., equivalent to 37 4-5 
tons per acre-foot, which is approxi¬ 
mately 150 times the amount in the 
East Coast soils, and 67 1-2 times the 
amount in the samples representing Or¬ 
ange, Hillsboro and DeSoto counties. 
It is evident from the foregoing that 
many of the Florida soils contain com¬ 
paratively small quantities of lime. The 
same is true, in a measure, of other 
bases, as magnesium, potassium, iron, 
etc. This is to be expected where a 
soil is composed so largely of sand. 
LIME EASILY WASHED OUT OF THE SOIL. 
Undoubtedly there was a time when 
these same soils contained much more 
lime than at present, but through years 
of cultivation and leaching it has been 
lost. The amount removed by crops 
each year, though small in most cases, 
must not be lost sight of, especially 
where no part of the crop is returned to 
the sdil. In addition to this loss there is a 
constant leaching going on which depletes 
the soil of its lime. From an examina¬ 
tion of the composition of drain-waters 
from unmanured land, it has been 
