Bulletin 229, Diseases of Citrus in Florida


disease, since virtually all known cases of scaly bark occur in
damp localities near bays, lakes, rivers or swampy hammocks.
Strange to say, in many groves where the disease was known
to have been very
severe i n former
years, it has decreas-
ed greatly within the
past few years with-
out any special steps
being taken to com-
bat it. This marked
decrease in the prev-
alence and severity
of scaly bark within
late years is believed
to be due to the in-
crease in the use of
fungicidal spra y s
and to the improve-
ment in grove man-
agement. At pres-
ent the disease seems
to be most virulent
in badly neglected or
abandoned groves.
 In 1925, grove in-
 spections of 10,000
 citrus trees that had
 been grown in scaly
 bark territory and
 set out at various
 points along the mid-
 dle East Coast show-
 ed no scaly bark in-
 fections. This a n d
 other investigations
 indicated that scaly
 bark should no long-
 er be classed as a dis- Fig. 33.-Scaly bark spots on sweet seedling
 ease of such impor- orange twigs, showing early stages of the
 disease. The youngest stages show as slight
 tance as to justify yellowish spots. (Twice natural size.)