38° 
when the oldest of the young fruits are about the size of an olive. 
Spray again about a month after the first application, after flowering 
has ceased and the youngest fruits are the size of a pea. <A. third 
spraying may be made a month later if it is found necessary, but 
two sprayings will probably be sufficient. 
In treating the orange and grape fruit for this disease, use Bordeaux 
mixture or ammoniacal solution of copper carbonate, prepared as indi- 
cated above. Two sprayings should be made, the first about two weeks 
after the flowers have fallen and the second about a month later. A Ver- 
morel nozzle and a pump giving a good spray should be used. The 
spray must be applied to the fruits in the form of a fine mist, covering 
them thinly and evenly. In this way the leaves will he sufficiently 
coated without any special effort being made to wet them. 
SUMMARY. 
1. Blight attacks trees only when over 5 years old and which are in 
bearing. It is first manifested by a sudden wilting of the leaves, 
which soon becomes so bad as to continue even in wet weather. At 
the beginning of the rainy season following the wilting, vigorously 
growing sprouts start from the trunk and larger branches. These often 
continue growing several years, but finally sicken and gradually 
decline. The spring following the wilting of the top, the branches, 
which have now become nearly leafless, bloom profusely. These flow- 
ers continue to appear for two or three weeks after normal blooming is 
over. They are small, however, and almost never set fruit. Very little 
fruit is produced by blighted trees. After flowering the branches 
usually die, often leaving only the sprouts from the trunk alive and 
growing. The whole top may be attacked at once or only a single 
branch, but in any case the entire top ultimately becomes blighted 
(Pl. IL). The affected trees usually linger for many years and rarely 
die outright, though they may be finally reduced to mere stumps. 
The roots, for the first year at least, seem perfectly normal. The annual 
loss from this disease in Florida is about $150,000. The cause is 
unknown, but it is probably a contagious malady, and, so far as known, 
is incurable. Affected trees should be dug up and burned as soon as 
they show the disease and healthy ones set out in their places. 
Die-back or exanthema is apparently caused by malnutrition, accom- 
panied by improper drainage, improper cultivation, etc. The disease 
may be recognized by the very large, dark, pointed leaves, and the 
reddish-brown stains on certain of the new-growth twigs, which later 
die back for a considerable distance (fig. 2, a). Brown eruptions (PI. 
III, fig. 3) oceur very abundantly on young and old twigs, all of which 
finally die back. Swellings produced by gum pockets in the wood 
occur very abundantly on the young twigs (fig. 2, b). Multiple buds 
form in the axils of the leaves (fig. 2,c and d). Diseased trees bear 
little fruit, and that formed soon assumes a pale green color, then a 
