Influence of Soil and Fertilizer on Citrus Fruits 
Prof, S. E. Collison. 
This discussion of the influence of cer¬ 
tain factors on the composition of the cit¬ 
rus fruit is based upon the analysis of 
approximately 600 samples of oranges 
and grapefruit made the past season by 
the Chemical Department of the Experi¬ 
ment Station. The principal kind of or¬ 
anges represented was the seedling, al¬ 
though we received samples of a num¬ 
ber of varieties, such as Parson Brown, 
Pineapples, Valencia etc. 
I wish to state that this work was 
made possible only by the generosity of 
the Florida Citrus Exchange. This or¬ 
ganization paid the salary of an addi¬ 
tional chemist, who gave his whole time 
in assisting in this work. It also paid 
the transportation charges on most of 
the fruit sent us. The Exchange was 
instrumental in having fruit sent us by 
growers located in the main citrus dis¬ 
tricts of the State. These samples of or¬ 
anges or grapefruit were received at in¬ 
tervals of a week or so throughout the 
season. 
At the same time a number of grow¬ 
ers not officially designated by the Ex¬ 
change sent samples also. In most 
cases one citrus tree was selected in the 
grove and the fruit on this tree carefully 
sampled every week. Twelve fruits 
were selected from the tree each time as 
representing the average of the fruit on 
the tree at the time of selection. So that 
each analysis reported represents a deter¬ 
mination made on twelve oranges or 
grapefruit. 
Full details relating to age of tree, 
type of soil, and methods of cultivation 
and fertilization were obtained from 
practically all the growers co-operating - 
with us. 
I wish to take this opportunity of ex¬ 
pressing our appreciation of the generos¬ 
ity of the Citrus Exchange for making 
this work possible, and also to thank all 
those growers who so generously gave 
their time and careful attention to the 
selection and forwarding of the samples. 
FLAVOR AND FOOD VALUE. 
The constituents which give the orange 
its flavor and for which it is valued as a 
food product are the acid and the sugars 
present. Certain essential oils influence 
the flavor without increasing the food 
value of the fruit. The acid present is 
mainly citric, the same acid as occurs 
in lemons and limes. There are three 
different sugars present, a little over half 
of the total sugar consisting of sucrose 
01 cane sugar, the remainder of dextrose 
or grape sugar, and of levulose or fruit 
sugar, the two being classed together by 
the chemist under the name of reducing 
sugar. Acid and total sugar go togeth- 
