The herald., 1896-07-18
address all communications of an ag-
ltor, The Herald Los Angeles, Call

4icultural nature to the Agricultural Ed
ttor, The Herald. Los Angeles, CAL
Bulletin No of the United States de-
partment of agriculture, division OF veg
stable physiology and pathology, treats
Of citrus fruits in Florida. The bulletin
Is finely illustrated. with color plates
and half tones; price 10 cents. We quote
what the bulletin says about FOOT rot ~
or mal-digomma.
Foot rot or mal-di COMMA Is dis
ease chiefly of the orange and lemon,
and is probably more widespread than
any other citrus malady. 1T Is known TO
occur in almost all countries where the
orange Is cultivated, but so far as known
appeared first In the Azores islands,
where 1t was very severe. According to
the statement of Fouque (2) it was first
noticed in this group in 1884, on the ISL
and Of San Miguel where 1t seems to
have originated. From that time until
1910 he estimates that fully one-fourth
of the trees were destroyed. 1treached
its greatest severity on the island In 1S40;
in 1912 1t bgan to decrease. and in 1873
1t had ceased to be very serious. f. AL
phonso go says that according to gener-
al report the malady appeared in Por-
tugal in 1915, In Hyeres in 1851, 1 in
Lago di Garda in 1855 and in MesSina In
1863. According to Briosi (5) the dis
ease first appeared in Sicily in 1862, and
afterwards spread to Naples, Liguria
and Lago di Garda, everywhere destroy
ing orange and lemon trees by thous-
ands. Professor Wohler mentioned in
Briosis monograph referred to In foot
note) found the malady very destruc-
tive on the Balearic islands in 1871. State
ments differ in regard to the first ap-
pearance Of the disease in Florida, but it
seems to have been noted here some
eighteen or twenty years ago. DR.. A.
H. Curtis CO. says: 1T appeared about
N lA,. .ol,
people remember to have observed it
earlier than 1880" The disease is widely
distributed in Florida, and has by no
means run out. but. on the contrary,
seems to be gradually spreading. 1t has
also appeared in Louisiana and Califor.
MIA, where, in places, it is said to be
very destructive
The damage caused by foot rot is
very great, and without question much
more than that caused by any other or
ange disease. The first season after the
trees are attacked they may bear an
unusually large crop of fruit, but this
is generally the last full crop produced.
BY the next season the tree Is either
killed or else SO reduced that 1t cannot
suppnrt ss-..-'- fs<-t+- Snmetimes tree
are nearly girdled in the space OF a rev
months. Whole groves have been en-
tirely destroyed in the course of a few
years. Briosi describes its effect in Italy
and Sicily as being most serious; he es-
Inmates the damage done in Italy from
1852 to 1873 at more than 50, 900, 00O In
Florida many fine bearing groves have
been almost totally destroyed. but the
malay does not appear to be so severe
here as In some foreign countries. The
annual damage 1t causes in Florida Is
estimated at about 100000
Symptoms-The first symptom of foot
rot fs an abundant exudation of drops
OF gum on the trunk Of the tree near the
OF the bark in the first stages of the dis
ease and may appear in one or several
distinct patches. In this stage the bar rk
VIII be found to be dscolred, having
become brownish, and to contain nuner-
GUS cavities filled with gum The inner
paIk becomes watery and more or less
Iotten. ana has very disagreeable, fe-
tid odor. AS the malady develops the
demarkation between the healthy bark
ana the diseased patches becomes very
apparent. The plant endeavors to throw.
on the disease, and separate layer is
formed between the healthy and dis
eased portions. The patch of diseased
bark thus delimited dries up the edges
preak away where the separate LAYER
IS FORMED and gradually curve IN In
crying. Finally the patches of diseased
park are thrown off Gig. So The death
ana decay OF the tissues caused by the
disease extend through the bark and an
parently for rome distance into the
wood. The cambium layer. the most
vital part of the tree, situated between
the park and the wood is DESTROYED
ana when the bark is thrown off therr
IS no possibility of new bark growing
over that portion. The patches of bark
which first become diseased are irregu-
Iar IN shape and vary greatly in size. but
are usually from l to inches in diame-
ter. The exudation of gum occurs nrin-
cipaliy IN the spring or in early autumn.
aiter the rainy season, while delimita-
tion and detachment of the bark usually
take place during the summer or winter
AS the disease progresses gum exudes
on other portions of the bark, which ara
IN turn thrown off. 1t is quite common
Tor circle of bark surrounding an old
uiseased spot to become affected and he
lnrown on, thus enlarging the spot The
malady gradually spreads in ali direo
lions, but principally down on the main
crown roots and around the trunk in a
Iateral direction Gig 81 Year after
yer other portions of bark become af-
lec.eu' until the tree Is entirely rirdle1
ana thereby killed. In malignant 90 soc
t tne olsease runs its course and kills
.ne tree IN two years or less. while in
sanua Iases the growth of the tree Is
tha ,, a1ected, and in a few years
ne WOUNDS are often completely cover
ed with the new growth fror, ti euxer- e,,
Inc obstruction of the bark on the tru,,I.
uoes not usually extend over I ~, ~
leet ABOVE the ground, but occurs IN +ha
face. oeioW the sur
frees aTected with foot ROT AMMAN.
nrst as II they We're suffering fro,,, - "a. ~
u, IT, ,ttouIiSnment. The foliage become,
,eIay ,isn. ysiioW ana scanty, the leaves do
tres hears Deims smaller than usual; the