ECONOMIC ASPECTS OF CITRUS-FRUIT GROWING IN FLORIDA 27 
of the variation was due to the difficulty of determining what was 
best. There was no difference in the fertilizer analysis because of the 
kind of fruit, the growers using the same kind for oranges, grapefruit, 
and tangerines. ‘Table 22 shows a distribution of the orange groves 
according to the percentage of the various elements of the mixtures 
used in the spring, summer, and fall applications. 
The variation in the percentage of the nitrogen and phosphoric 
acid materials was not so great as the variation in the percentage 
of potash used. There was a tendency to use more nitrogen in the 
spring than in the summer and fall applications; 3 to 4 per cent of 
nitrogen was used in the spring, whereas in the other two applications 
the majority of the growers used 3 per cent of nitrogen. Most of 
the growers used from 6 to 8 per cent of phosphoric acid in the mix- 
tures for all applications. There was considerable difference in the 
percentage of potash used in the mixtures. The most common 
amounts used were: Spring, 5 per cent; summer, 5 per cent; and fall, 
10 per cent. The tendency was toward a gradual increase as the 
season advanced. 
TABLE 22.—Number of growers using various percentages of nitrogen, phosphoric 
acid, and potash for spring, summer, and winter fertilizing, in 1922 
Nitrogen Phosphoric acid Potash 
. x pees! 
easou usua 
: Total Total Total 
analysis petcent: growers Reroute growers perieat growérs 
8 using 8 using 8 using 
Per cent | Number | Per cent | Number | Per cent | Number 
STN a ea Eee SE 2-8-5 2 1 3 1 2 i 
3 32 4 1 3 17 
4 28 5 1 4 2 
5 4 6 12 5 21 
6 3 7 5 6 8) 
eae eee So ee 8 45 7 3 
eps tle es |S ha 9 2 8 8 
eae ie ey a a ae 15 Bi 10 7 
SUMIN Ors eet ee ye 3-8-5 2 4 3 1 3 6 
2 4 4 2 4 1 
3 50 5 1 5 21 
4 14 6 20 6 13 
6 4 7 2 7 3 
are pean let 8 44 8 17 
SRE Se Se eae ee aes 9 1 10 11 
Nefrol fae tl ee OS Siete 15 If | aA Bed | NSP 2S 
Wallis corey i a Se eee eh 3-8-10 oD) 1 3 if 2 il 
2 9 4 2 3 3 
3 45 5 2 4 2 
4 10 6 17 5 15 
5 1 7 5 6 5 
6 1 8 42 7 6 
a ee LR aE (ee ae reel Pe roe 8 16 
sie ntinkceuee arate [pies Bloc were ne oe | oon 10 20 
fae Sa pees oe eeemed (ieee Yee ape Sie [ee Weer ee 12 1 
The quantity of spray material used per tree varies as much if 
not more than the quantity of fertilizer used per tree. The ill effects 
of too little fertilizer as compared with the use of too little spray is 
perhaps more apparent to the casual observer because of radical 
change in the appearance of the foliage where plant food is deficient; 
but viewed with respect to the yield and quality of the fruit, the 
information obtained seems to indicate that spraying is quite as 
important as fertilizing. 
Information relative to the analysis of the sprays used was not ob- 
tained in all cases. It was believed, however, that the sprays used 
