COOPERATIVE EXTENSION WORK IN AGRICULTURE AND HOME ECONOMICS
(Acts of May 8 and June 30, 1914)
Agricultural Extension Service, University of Florida,
Florida State University and United States Department of Agriculture, Cooperating
H. G. Clayton, Director
Controlling Mango Insect Pests
D. 0. WOLFENBARGER
University of Florida Sub-Tropical Experiment Station
Fig. 1.-Mango shield scale.
Single copies free to Florida residents upon request to
AGRICULTURAL EXTENSION SERVICE
Controlling Mango Insect Pests
D. O. WOLFENBARGER
The mango in Florida has but few serious insect pests. Those
pests which may be serious can be easily and satisfactorily
controlled. Although there is much to be learned about our in-
sect pests, this lack of knowledge is no deterrent to commercial
Insect pests attacking mango roots are almost unknown. Two
weevil larvae taken from dying seedlings were submitted to the
U. S. Department of Agriculture for determination. Reports
were received that no such larvae were in the Department col-
lections, hence the species involved is unknown.
However, insect pests infesting the mango may be found on
trunk and branches, twigs, leaves, blossoms and fruit. A pest
species is frequently restricted to a given part of the tree.
Insect Pests Infesting Trunk and Branches
Infestations of the lesser snow scale, Pinnaspis strachani
(Cooley) (Fig. 2), are common on the trunks, especially of the
smaller trees, and on lower branches of larger trees. Results
from severe infestations include cracking of the bark and exuda-
tion of sap. Applications of 1 gallon of emulsive oil or of 1
pound of 15% wettable powder of parathion per 100 gallons
of water control this insect.
Ambrosia beetles (family Scolytidae) of several species have
been taken from mango trees. Burrows made by these beetles
are as small or even smaller than the lead in a lead pencil.
Beetles may tunnel directly into the trunk and branches, or they
may burrow around the bases of twigs, grafts (Fig. 3), limbs
and leaves. Beetles carry fungi with them which grow in the
galleries constructed. Mycelia grow in the sap-logged wood and
serve as food for the beetle larvae. The fungal growth gives rise
to "blue stain" in the wood. Fungal growth extends terminally
and basally from the beetle gallery in the mango tree and in
some instances kills the tree. Trees with souring and stagnant
sap flow are attractive to these beetles. Such trees include those
cut back for grafting and those injured by wind. Large trees
.f that have been trans-
planted also may be at-
p *Retention of tree vigor
and prevention of injur-
Ssies are the most satisfac-
tory control measures.
il4 For those who wish to
r .apply control measures
benzene hexachloride at
S2 pounds of 10% gamma-
isomer content wettablee
powder) or lindane at 1
pound of 25% gamma-
isomer content wettablee
powder) per 100 gallons
of water is suggested.
Larvae of flat-headed
and round-headed borers
SP belonging to the beetle
i families Cerambycidae
and Buprestidae are fre-
Fig. 2.-Lesser snow scale on trunk of quently found in weak-
young mango tree. Small whitish-colored ened, dying and injured
insects are in crevices of bark, especially trees and branches and
in lower part of figure. Between 1i and r hes
natural size. around the bases of cuts
and wounds. Such infes-
tations are indications of weakened trees or areas, since the
larvae are repulsed by trees in full vigor. The maintenance of
vigorously growing trees is obviously an excellent control
Insect Pests Infesting the Leaves
The red-banded thrips, Selenothrips rubrocinctus (Giard)
(Fig. 4), appears to be present at all times on some mango
trees. Its enemies and unfavorable conditions usually keep its
numbers low, but at intervals it becomes abundant and causes
defoliation (Fig. 5). Tests with most of the newer insecticides
have shown that dieldrin is the most effective in thrips control.
One pound of 25%o (1/2 pound of 50%) wettable powder of
dieldrin or 1 pint of the emulsion concentrate (11/ pounds per
gallon) per 100 gallons of water is the recommended amount.
Dieldrin may be used satisfactorily with copper or carbamate
fungicides, or with parathion or sulfur for insect pest control.
Scale insects and mites are the principal annual insect pests
infesting mango leaves. Scale insects are, or may be, present
at all times. Mites are more abundant during the dry months,
November through March.
Fig. 3.-Ambrosia beetle burrows about base of small twigs.
Three to four times natural size.
Scale insects infesting the leaves are undoubtedly the most
serious of all mango insect pests in Florida. The soft scales,
pyriform, Protopulvinaria pyriformis Ckll. (Fig. 6); mango
shield, Coccus mangiferae (Green) (Fig. 1) ; acuminate, Coccus
acuminatus (Sign.); and Florida wax, Ceroplastes floridensis
Comst. (Fig. 7), are commonly observed. The armored scales,
Florida red, Chrysomphalus aonidium (L) (Fig. 8), and
dictyospermum, C. dictyospermi (Morg.), become abundant on
the mango at times. They may infest twigs and leaves.
Control of the pyriform, mango shield and acuminate scales
may be accomplished with emulsive oil, parathion or malathion.
One gallon of emulsive oil or 1 pound of 15'% wettable powder
of parathion per 100 gallons of water is effective. Three to 4
pounds of 25% wettable powder of malathion per 100 gallons
of water may be used.
Fig. 4.-Nymphs (adults are black) of red-banded thrips on lower mango
leaf surface. Excremental remains and cast skins may be observed. About
six to seven times natural size.
Control of the Florida wax scale is apparently more ditticult
than that of the other soft scales. A spray application in De-
cember of 11/ gallons of emulsive oil combined with 1l/1 pounds
of 15 / wettable powder of parathion in 100 gallons of water was
very effective. Armored scales are more difficult to control than
are the soft scales. Emulsive oil, 1-11/. gallons, or parathion,
11i-2 pounds of 15%/ wettable powder per 100 gallons of water,
is recommended for armored scale control.
The upper surfaces of leaves frequently become reddish colored
from the feeding of mites. Leaf fall may follow severe infesta-
tions of mites. Mites also infest the bloom and young fruit.
Many mites feeding on the young fruit may cause it to fall.
Fig. 5.-Tree with defoliated twigs from infestations of red-banded thrips.
Two species of mites infesting mango leaves have been recog-
nized. The most common species is the avocado red mite, Para-
tetranychus yothersii (McG.), especially south of Miami. The
tumid mite, Septanychus tumidus (Banks), is less common
around Miami but may be more abundant around West Palm
Beach. There is no method for distinguishing between the mite
species except through microscopic examination of the male
Fig. 6.--Pyriform scale on leaf.
Sulfur is effective in the control of the avocado red mite. It
may be used as a dust, 1/2 to 8 ounces per tree depending on its
size, or as a spray composed of 10 pounds of wettable sulfur per
100 gallons of water to wet the foliage. Since sulfur appar-
ently does not control the tumid mite, some other miticide is
recommended for it. Emulsive oil or one of the newer miticidal
preparations may be used. Three to 4 quarts of emulsive oil
per 100 gallons of water is recommended as a spray for control
Sprays containing oil are "shocking" to the trees, especially
under certain weather conditions and if more than 11/3 percent
oil is applied. If trees are suffering from lack of moisture, as
near the end of the dry season, oil may cause the leaves to fall,
especially if unusually low temperature follows the application.
Oil in concentrations strong enough to give satisfactory control
of the armored scale may "burn" many leaves if the temperature
goes above 900 F. soon after the application. Emulsive oil
sprays are usually more effective if considerable pressure (400
psi) is used in the application. About four weeks should
precede or follow the application of an oil emulsion spray if sulfur
is to be used. Neither oil emulsion nor parathion sprays can be
Fig. 7.-Florida wax scales on mango leaves. About two to three times
expected to give perfect control of the armored scales on mangos.
Thorough applications of 11/-11/ /o oil at high pressure (400-450
psi) occasionally give 90% control; but more often 75% con-
Since some of the phosphate insecticides are effective in scale
insect control they are often used for such purposes. Although
parathion is the most effective of these materials, others such as
malathion and demeton may be applied. These materials may
be used alone or in combination with emulsive oil. A combina-
tion of 3 quarts of emulsive oil with 1 pound of 15% wettable
powder of parathion is effective in the control of scale insects
and spider mites. This combination is often recommended as a
general purpose spray for mango insect control, since the amount
of oil is low and is safe to plants and the amount of parathion
is not high. One application of this combination made after fruit
harvest ordinarily will give satisfactory scale control for a year.
Although the phosphate materials give immediate but tem-
porary mite control, they are not recommended for control of
these pests. More mites have been found on sprayed trees than
Fig. 8.-Florida red scale on upper surface of mango leaf. About four
times natural size.
.4 Arr I fi
r) u^f,,L -
7 PI ~
on unsprayed trees a month after the application. Severe mite
populations have been observed in commercial groves a month
to six weeks following the application of phosphatic insecticides.
The phosphatic insecticides presumably kill parasites and preda-
tors feeding on the mites. If phosphatic insecticides are applied
during or just preceding the months (November through March)
that mites are or-
some effective miti- j
cide may be needed.
Emulsive oil or ovo-
tran may be com-
bined with the phos-
for mite control.
A sweetish mate-
rial is secreted by the t
scale insects, white-
flies, mealybugs and dI
leafhoppers which in-
fest the mango. Al-
though the exudate
is nearly colorless,
the leaves may glis-
ten with the residue
if it is abundant. It
is frequently called
grow and develop on Fig. 9.-Citrus mealybug (whitish-colored
objects) on mango fruit. About one-half natural
the sweetish deposit. size.
The color becomes
black and has a sooty appearance. Both the exudate and the
resultant sooty covering are probably detrimental to normal leaf
activities. The residues are unsightly on the leaves and detract
from the market value of the fruit. Control of the insects exud-
ing the honeydew controls the black sooty mold. A period of
time, weeks or even months, of exposure to winds and rains is
required to cause fall of the sooty mold.
The banded cucumber beetle, Diabrotica balteata Lec., oc-
casionally causes serious damage in its feeding on the tender
leaves of new growth. Young trees have been more severely
infested. Benzene hexachloride at 2 pounds of 10% gamma-
isomer wettablee powder) per 100 gallons of water has been rec-
ommended as a spray for control of the beetle.
Insect Pests Infesting Mango Bloom
Infestations of Florida flower thrips, Frankliniella cephalica
(D. L. Crawford), are common in mango bloom, although the
amount of harm to the plants they do or of value they do in pollina-
tion is doubtful. Two tests were conducted to reduce the thrips
and to determine any value from the reductions. Counts made in
one test showed that thrips had been greatly reduced. Counts of
fruit in both tests just preceding harvest showed there had
been no increase in fruit on sprayed trees over those unsprayed.
Fig. 10.-Fruit blotch miner on mango fruit.
hatching, but as it grows the mine also becomes
four times natural size.
Miner larva is small at
larger. About three to
Although an earlier bulletin on mango insects (Moznette,
G. F., Insects Injurious to the Mango in Florida and How
to Combat Them, USDA Farmers Bulletin 1257, 1922) listed
the blossom anomala, Anomala undulata Mels., as a pest of
r .~. sn~sl,
mango bloom, there has been no report within the last decade of
an infestation of this beetle.
Two lepidopterous larvae, one without a common name,
Argyrotaenia amatana (Dyar), and the cotton square borer,
Strymon melinus (Hbn.), have been found feeding in bloom
panicle. A. amatana (Dyar) spins webs and encloses the bloom
for its protection. It is common in mango groves but has not
been abundant enough to warrant a control recommendation.
Insect Pests Infesting Fruit
The citrus mealybug, Pseudococcus citri (Risso), may become
very abundant on the growing mango fruit (Fig. 9). Only a few
fruit on a tree may be-
come infested but these
may become very un-
sightly. Such fruit may
be irregularly spotted so
that it is unattractive at
market. Mealybugs may
be dislodged by a stream
of water under much
pressure or by stroking
fruit with a soft-bristled
brush. Spray applica-
tions of 1 pound of 15%
wettable powder of para-
thion or of 4 pounds of
25% wettable powder of
malathion per 100 gallons
of water are suggested
An occasional fruit is
found with a surface
blemish caused by a fruit
blotch miner (Fig. 10).
This blemish is an irreg-
ular mark made by the
flattened larva of an in- Fig. 11.-Papaya fruit fly larva in papaya
fruit. About 1/2 natural size.
sect as it burrowed in
the peel of the fruit. Although the insect species is not known,
it is likely to belong to the Order Lepidoptera, as a mem-
ber of the Gracilariidae family, a tiny moth. One terminus
of the mine may be observed as small, while the other is much
larger, indicating that the larva increased in size and that the
mine increased in width. No control effort is recommended.
Larvae of the papaya fruit fly, Toxotrypana curvicauda
Gerst, are found occasionally in mango fruit. Owing to the ab-
sence of external symptoms, it is difficult or impossible to distin-
guish an infested fruit (Fig. 11) without cutting into flesh, i.e.,
until the fruit decay has made a soft area.
Three suggestions are offered for prevention of infested fruit:
(1) Bagging mangos, (2) observation of developing mangos and
destruction of any papaya fruit fly found and (3) separation of
papaya and mango groves by one-half mile or more.
Scale insects may become abundant on the fruit and if so
cause a spotted, unattractive color which reduces the value.
Such infestations should be controlled before they infest the fruit.
Suggested Schedule for Observation for Pest Control on
This might be termed an insect pest control program, except
that not all pests will be present each year. It is prudent to
make careful examinations of trees for insect pests and apply
measures for control only when they are needed.
Period Pest to Look for
Where to Look Control
On upper leaf surface, Sulfur*
along midrib, near ter-
Leaf surfaces, upper Parathion c
and lower emulsive oi
On upper leaf surfaces Sulfur*
along midrib, near ter- I
minus of leaf
Surface of fruit, in clus- Mechanical
ters behind leaves
Leaf surfaces, upper Parathion o
and lower emulsive oi
SLower leaf surfaces, Dieldrin
If sulfur is not satisfactory in control another miticide should be used.
** A most opportune time for scale insect control is the period immediately following
t These insects may be found soon after harvest until the pre-bloom period.