soil are most susceptible, but no locality in the State is entirely cxempt. 
5 The malady has been known for at least twenty and possibly twenty- 
five years. The first reliable account of it, however, was Se ee ims 
1891! by Prof. L. M. Underwood. 
Blight never attacks trees until they have attained considerable size 
and have begun to bear fruit. In any given grove usually only a small 
4 per cent of new cases occur each year, but the fact that the disease is 
£ apparently incurable and that it attacks the oldest and most vigorous 
as and fruitful trees in the grove renders it one of the most destructive 
maladies known. It is widely distributed over the State, occurring in 
fe the oldest and best groves and on the land best suited for profitable 
orange culture. The affected trees do not die at once, but apparently 
revive when the rainy season commences. In this way false hopes are 
aroused and the owner waits for years before he finally removes the 
blighted trees and replaces them with healthy ones. Much time and 
money have been wasted on supposed cures, the worthlessness of which 
. ote: does not become apparent until after several years’ trial. In some local- 
Sell ities from 1 to 10 per cent of the trees blight annually. The annual loss 
| resulting from this disease in Florida is from one to two hundred 
Sy thousand dollars. Within the last ten years it has caused losses prob- 
s ably amounting to several million dollars. 
Symptoms.—Blight usually appears very suddenly and on trees that 
have previously seemed perfectly healthy. The first symptom is a wilt- 
ing of the foliage, as if the tree were suffering from drought (fig. 1). 
At first the wilting is slight and can be plainly seen only on hot, dry days; 
but it soon becomes very pronounced, and often continues so during the 
wet season in Summer, when rains are almost a daily occurrence. Most 
x cases of blight appear in early spring, from February to April, which 
* is usually a dry season. Sometimes, however, cases occur in midsum- 
St mer, When the ground is thoroughly wetted every few days. After the 
: wilting becomes severe the foliage begins to drop, and in a few weeks 
i. to a few months, according to the severity of the case, the affected 
( branches shed nearly all their leaves. In many cases the whole top of 
% the tree is attacked at one time, but very often only a single branch 
Cam shows the disease at first. In such cases, however, the entire tree soon 
becomes affected. 
As soon as the rainy season begins the trunk and larger branches 
ig put forth numerous water sprouts, which grow rapidly and at first 
- seem to be perfectly healthy. Eventually, however, these sicken and 
| gradually die back. The branches which first showed the blight usually 
Za retain for a year or more some foliage, which is abnormally small and 
d F of a dingy green color. New growth is very sparse and does not pro- 
e duce normal-sized leaves. Such branches often show green twigs all 
re over, even when nearly leafless. In the spring following the first wilt- 
ing (unless it occurs late in winter, when it is not until the second 
1 Journal of Mycology, Vol. VII, pp. 32-34. 
