no 
FLORIDA STATE HORTICULTURAL SOCIETY. 
nitrogen or potash. This is shown in results obtained in our experimental 
Table 2, the figures for which are taken grove. This grove is located on the bor- 
Table II. 
FERTILIZING CONSTITUENTS IN THE LEAVES, STEMS AND FRUIT OF THE ORANGE. 
Compiled from Analyses made at the Florida Agricultural Experiment Station. 
Nitrogen. 
Phos. Acid. 
Potash. 
Lime. 
Leaves, dry. 
2.04 
.607 
2.52 
3.01 
Stems, dry. 
1.00 
.424 
I.I 5 
1-39 
Fruit, fresh. 
.12 
•054 
.29 
• • • • 
Ash of fruit. 
• • • • 
8.63 
52.05 
22.77 
from analyses made at the Florida Ex¬ 
periment Station. 
From this it is seen that the amount of 
potash in the leaves is more than four 
times as great as the phosphoric acid, 
while in the fruit the amount of potash is 
nearly six times as great as the phosphoric 
acid. When we couple this faqt with the 
further facts that the phosphoric acid is 
not lost in the drainage waters to an ap¬ 
preciable extent, and that our soils are 
almost universally deficient in potash, we 
are led to ask the question, “Have not, in 
some cases at least, our formulas con¬ 
tained relatively too much phosphoric acid 
or too little potash? In the light of the 
facts before us, is a formula containing 
7 or 8 per cent, available phosphoric acid 
and 8 to 10 per cent, potash a rational 
one?” Without stopping to give a di¬ 
rect answer to this question at present, 
we may ask the further question, “Is it 
necessary to apply phosphoric acid so 
often as we are accustomed to do?” To 
answer this question I will refer briefly to 
der of Lake Harris, and the soil is a 
brownish red, coarse sand, well supplied 
with natural phosphate. The trees were 
set out in January, 1909, nearly two and 
a half years ago. One plot out of forty- 
eight receives no fertilizer whatever; and 
while this plot is not the best, it does stand 
well up in the list, its rank being twelfth 
in increase of size, as determined by 
measurement of the trunk. But for a 
slight yellowing of the leaves, indicating 
the need of nitrogen, it would be impos¬ 
sible except by the merest accident for a 
stranger to pick it out from among the 
other forty-seven plots, all of which have 
been fertilized. We also have in this 
grove four plots which have received their 
phosphoric acid in the form of finely- 
ground raw rock. These also stand well 
up in the list of those having made the 
best growth, one being second, another 
sixth, another nineteenth, and another 
twenty-second, all in the first half. While 
we should not be too hasty in drawing 
conclusions until the work has pro- 
