38 
FLORIDA STATE HORTICULTURAL SOCIETY 
spraying for the control of the Rust Mite. 
If the spray is applied in time to kill this 
pest before it begins to damage the rind 
of the fruit, the spray is effective. If we 
wait until the surface of the fruit ap¬ 
pears mealy from the presence of large 
numbers of them, we may be assured that 
the mite has begun to do damage, and that 
the spray will not be entirely preventive. 
Therefore, to be timely, there should be 
regular periods of inspection of the trees 
with the aid of the hand lens and when 
the mite is found on the leaves or has 
begun to move onto the fruit, then spray 
at once. 
Now, not all citrus trees of the same 
stock and variety are alike. We have all 
noticed this individuality of the tree in 
the grove and in the nursery. It is due 
to certain inherent qualities within them. 
For example, two trees located side bv 
side in the grove that are of the same age, 
size and appearance may differ as to the 
amount of fruit that they will bear or 
they may differ as to vitality. These in¬ 
herent differences we endeavor to control 
by the proper selection of stocks and bud- 
wood in the nursery. 
Again, there are certain inherent dif¬ 
ferences in different stocks whereby some 
will survive under conditions beyond our 
control and others will not. Therefore 
we have to select to obtain the proper 
stocks for a given locality. 
The art of handling a citrus grove for 
the production of fruit consists entirely 
in the practice of the methods for the con¬ 
trol of those conditions which have been 
referred to. In applying these methods, 
we judge our results by certain appear¬ 
ances of the tree, such as color of the 
leaves, types of growth, and by the quan¬ 
tity and quality of the fruit. . For exam¬ 
ple, if we see a certain type of yellowing 
in the foliage of our trees, we recognize 
it as nitrogen hunger, a certain crinkly 
waxy appearance of the leaves indicates 
too much phosphoric acid; and certain 
malformations indicate the presence of 
certain diseases; etc. 
From experience based on long prac¬ 
tice, there are certain of these methods 
which for the most part we employ regu¬ 
larly without any particular reference to 
the tree, whereas in the case of others, 
we employ them only when appearances 
of the tree or conditions warrant their 
use. For example, we may have a regular 
method of cultivation which we follow 
each year' without any particular varia¬ 
tion; or we may have a regular time for 
the application of fertilizers which we 
follow more or less blindly. On the other 
hand we consult the tree as to what kind 
of fertilizer we will use, as to whether or 
not we will prune, spray or irrigate. 
I have thus reviewed in a general way 
the growth conditions in the grove, the 
functions of the tree which these condi¬ 
tions affect and finally, the methods we 
use in the control of these conditions, or 
in other words the methods we use in 
grove practice. It goes without saying 
that our information on these subjects is 
by no means complete. Then what are 
some of our needs that we may handle 
our groves more intelligently and to bet¬ 
ter advantage? On thinking it over, we 
find that our needs are as broad as those 
of science itself. In other words in order 
that we may grow good trees and much 
good quality fruit with greater certainty 
