18 
the fruit, exposing the segments and causing the orange to rot and 
fall (fig. 4). 
12. Both the fruits which fall early and those which come to full 
maturity are usually more or less disfigured by irregular brown stains, 
similar to those occurring on the twigs. These stains frequently cover 
a large portion of the fruit, rendering it unsalable (P1. ITI, fig. 2). 
13. Slight swellings are sometimes found on the rind, particularly in 
the sour orange. These swellings are caused by gum pockets formed 
within the tissue of the rind. Very frequently a formation of gum also 
occurs in the segments immediately around the axis, generally near the 
seeds. 
14, The fruit of trees affected with die-back usually ripens consider- 
ably earlier than that of adjoining healthy trees of the same variety. 
Fig. 4,—Orange fruit, showing effects of die-back. 
As arule, however, itis large, very coarse, thick skinned, and disfigured 
with brown stains, and in consequence often unsalable. - 
15. The roots of trees affected with the disease usually have a 
healthy appearance, but in severe cases, on improper soils, they fre- 
quently become ulcerated and die back for some distance, the dead 
ends rotting away. Roots which have died back frequently have large 
and somewhat swollen ends, from which later on a number of small 
roots frequently arise. 
The order in which the symptoms appear and their severity vary 
ereatly, but generally are as follows: The first sign of the disease is the 
unusually dark-green color of the foliage, rank growth, and large, 
thick-skinned fruit. These symptoms are soon followed by the staining 
and dying back of a few twigs, and by brown stains formed on some 
