Persimmon Pest Management in the San Joaquin Valley - AAIE

Persimmon Pest Management in the San Joaquin Valley
By Devin Carroll
Revised 2013
Persimmon is a minor crop in California, and so far it has no University
of California pest management manual or website section in the UC IPM
Project. UC IPM does have some information in the ornamentals section.
UC Division of Agricultural Science has a 1982 leaflet, Growing
Persimmons, but so far I have not located a copy to read. 6
In this paper I summarize what I have learned during several years of
monitoring some blocks of Fuyu and Hachiya persimmons near Earlimart,
and one young block of Fuyu persimmons near Reedley. I will cover only
arthropod pests.
Most of the pests I have seen on persimmon are also pests of pistachio,
so the information in the pistachio section of the UC IPM Project is very
useful. 8
The list of insecticides registered on persimmons is very short.
Conventional insecticides include various brands of imidacloprid and the
miticide Apollo (Omite and Acramite can be used non-bearing). Recently
the Movento label added persimmon, and Nichino expects to register
Applaud in 2013.
Soft chemicals include pyrethrin, some neem products (azadirachtin),
specialty oils (Ecotrol) and Bacillus thuringiensis (B.t.).
Lepidoptera
UC IPM lists fall webworm (Hyphantria cunea) and redhumped
caterpillar (Schizura concinna) as pests of ornamental persimmons. 7 So far I
have not seen them.
New Zealand authorities report light-brown apple moth (Epiphyas
postvittana), as a pest of persimmons. 2 LBAM is now present and spreading
in California, and persimmon growers should watch for it. LBAM is a
leafroller similar to oblique-banded leafroller (OBLR, see below).
Quarantine may be its principle economic hazard.
In the south Atlantic states the persimmon borer, Sannina uroceriformis,
a clearwinged moth (Sesiidae), is a pest of American persimmon. The larva
“may bore seventeen to twenty-two inches below the surface of the ground
or in the trunks aboveground.” 3

One persimmon grower informed me that Mexican authorities identified
OBLR in shipments of his persimmons, which were then rejected because of
their quarantine. I have not found literature references to OBLR in
persimmon. I have seen leafroller damage, but so far I have not identified
any worms. I presume that the damage is caused by OBLR, but possibly
some other tortricid worm such as omnivorous leafroller (OLR) could be
involved. Treatment timed for OBLR seems to help.
Oblique-Banded Leafroller (OBLR)
Choristoneura rosaceana
OBLR is a large leafroller that
feeds in a silk nest, usually underneath
the calyx or under an old flower stuck
to the fruit. Typically, the calyx is
damaged more than the fruit, but calyx
damage may result in a cull even if the
fruit itself is unmarred. Under old
flowers the fruit skin is more often
damaged. Also, OBLR worms are
forbidden in shipments to Mexico,
which is a major importer.
This Fuyu flower has persisted on
the fruit, providing protection for
OBLR feeding underneath.
Treatment of the second and third
generations can be timed using
pheromone trap biofixes and degree
days. UC IPM Online has a degree day
OBLR damage to calyx.
OBLR has three generations in
the San Joaquin Valley. 8 Second
instar worms overwinter under
bark. They emerge in late March or
early April to begin feeding on
leaves. This approximately
coincides with pistachio bloom, and
is an effective timing for B.t.
sprays.
Flower removed showing damage.

model. Traps should be placed by mid-April (Kern, Tulare, and Kings
Counties), or April 25 (Fresno and north). I usually catch 1-2 OBLR moths
per month, but every week I find hundreds of the garden tortrix, Ptycholoma
peritana, a much smaller moth, about the size of an OLR, which breeds in
weeds.
OBLR biofixes and degree day updates for Fresno and Tulare counties
are available from Sticky Notes, maintained by Kelley Morrow, at
www.ipm2go.com.
I have not seen OBLR damage a high percentage of persimmon fruit,
even when untreated. 1-2% damage can occur.
I usually treat the first generation with B.t., and often the second
generation. Treatment of the second and third generations is hampered by
the difficulty of reaching the larvae hiding under the calyxes.
Mealybugs
UC IPM lists Comstock (Pseudococcus comstocki), Gill’s, and
longtailed mealybugs on ornamental persimmons. 7 I am confident that I
commonly see grape mealybug. Recently John Hubbard of Nichino has seen
long-tailed mealybug causing problems on persimmons near Reedley. I
have not seen Comstock
mealybugs.
In my opinion the best
available materials for all these
materials will probably be
Movento and Applaud, timed
for the crawlers in early to
mid-June.
Gill’s Mealybug
Ferrisia gilli
Gill’s mealybug,
sometimes called striped
mealybug, is by far the most
damaging pest of persimmons
when it occurs unchecked by
natural enemies. Hundreds of
mealybugs will cluster on each
fruit, and in the worst areas,
100% of the fruit can be
Long thin wax filaments characterize Gill’s
mealybugs.

uined.
Gill’s mealybug can be distinguished from grape and other mealybugs
by its long hair-like wax filaments from the dorsum.
Gill’s mealybug produces live crawlers without an egg stage. On
pistachios, it has three generations per year. 8 Based on my observations in
persimmons around Earlimart, it appears that the three generations might be
maturing a little earlier on persimmons than on pistachios.
Females mature in late fall and produce crawlers that overwinter in
hidden spots on the trunk. 8 At budbreak in pistachios the crawlers begin
feeding on the new buds, and they mature around the end of May. In
persimmons in 2010, I first noticed half-grown crawlers at the end of March,
and they matured at the end of April. Most of these adults moved to the
trunks. They began producing first generation crawlers by May 13. The
crawlers migrated to the leaves. They matured starting in early July, and
moved off the leaves to nearby woody branches. Many began finding fruit
at this time. This compares to maturity in “mid-July” in pistachios. 8
Second generation crawlers appeared in the persimmons by July 14.
Many congregated on fruit, especially around the calyx, or where two fruit
touched, or at the tip of the fruit. These mealybugs matured near late
August, compared to “mid-September” in pistachios. 8 Third generation
crawlers appeared in persimmons by September 8. This is the overwintering
generation, which moves off the fruit back to the trunk.
The best time for chemical control of Gill’s mealybug is late May to
early June, when most are small crawlers on the leaves. By early July and
afterwards, too many are hidden under calyxes or between fruit. Movento
might work even in areas protected from direct spray. We tried Aza-Direct
at 32 oz. with 5 oz. Nu-Film 17 in 150 gallons water, but not many
mealybugs died. Perhaps a higher rate or better coverage would be more
successful. Imidacloprid works moderately well, but it has not tested well
compared to Applaud or other choices, and it is harmful to parasites and
predators (pers. comm. David Haviland, and my observations in grapes). I
suspect that use of imidacloprid to control soft scales in
2007-08 lead to the severe mealybug problems I
observed in 2009-10.
In some instances, infestations of Gill’s mealybug
in persimmons have disappeared before causing much
damage (Haviland). Presumably natural enemies
Parasitized
mummy.
achieved this control. Natural enemies also control
Gill’s mealybugs in almonds (Haviland). In some
sections of the Earlimart persimmons in 2010, I found

evidence that these predators and parasites were providing adequate control.
But in other sections, the population reached very damaging levels. In 2011-
12 the population decreased to cause only spotty moderate damage, without
any treatment.
The only parasite I have seen is Anagyrus pseudococci. Other parasites
known to attack Gill’s mealybug include Pseudaphycus sp. and
Chysoplatycerus sp. 8 I found only 1-10% parasitism in the heavier Gill’s
infestations, but this parasite probably is a key to control where populations
are low and at the end of the season. Brown lacewings are known predators,
but I did not notice any. Green lacewings contributed significant predation.
The predaceous gall midge, Dicrodiplosis californica, often feeds on
mealybugs massed under calyxes. This midge is a key to control of grape
mealybugs in vineyards. The lady beetle Nephus sordidus or “little brown
mealybug destroyer” may also be an important Gill’s predator. The larvae
have waxy coverings that make them resemble mealybugs.
Grape Mealybug
Pseudococcus maritimus
Grape mealybug (GMB) can be a significant pest of persimmons, but not
nearly as bad as Gill’s mealybug. GMB has two long waxy tails.
The generational history of GMB on
persimmon is similar to that on grapes.
Egg masses overwinter, sometimes with
crawlers hatched. They finish hatching
in late February and move out to the
buds and leaves. As they near maturity
they move back to the trunk, where they
produce egg masses starting in mid-May.
New crawlers hatch beginning in early
June, and by the end of June most have
moved out to the fruit and leaves. This
second generation matures beginning in
late July. Some may create egg masses
on the fruit under calyxes, but the
majority returns again to the bark. Most
are gone from the fruit before harvest.
Predaceous gall midge maggot with grape
Mid to late June is a good time for
mealybugs on grape pedicel.
chemical control. Late March might also
be good. We also had fair success with
25 oz. Aza-Direct, with 5 oz. Nu-Film 17 in 150 gallons water, applied June

28 in 2008. I found many dead bodies, and by July 14 I could find only a
few exposed that were alive. However, there was a fair number hidden
under calyxes.
GMB has good biological control in persimmons. I suspect that the
trouble we had in 2008 was partially caused by two years of applying
imidacloprid to control soft scales. Natural enemies are the same as in
grapes: predaceous midges, the “little brown mealybug destroyer”,
lacewings, and parasites in the family Encyrtidae.
Longtailed mealybug
Pseudococcus longispinus
This information is gleaned from
UCIPM sections on avocado and citrus
and from correspondence with John
Hubbard of Nichino America, who has
observed this species at serious levels
in persimmons near Reedley.
Longtailed mealybug is
distinguished by extremely long wax
tails. In citrus and avocado, this
species has 2-4 overlapping generations
a year. It is typically controlled by
natural enemies including the usual
predators and the parasites
Acerophagus notativentris,
Arhopoideus peregrinus, and
Female long-tailed mealybug.
Photo by David Rosen from UCIPM.
Anarhopus sydneyensis. A.
notativentris is also the most common parasite of grape mealybug.
In persimmons, the life cycle is similar to Gill’s mealybug (Hubbard).
The generations may be more distinct than in citrus and avocado. Females
give birth to live young and crawlers can be seen emerging in the first two
weeks of June. This should be good timing for Applaud or Movento and
coincides with timing for other mealybugs and soft scales. Another
generation of crawlers emerges beginning in August and continues for
several weeks into September. In both generations they can be found on the
scaffold branches, the leaves and the fruit, especially under the sepals. They
produce copious amounts of honeydew on the fruit, leading to black sooty
mold which makes the fruit unpackable.

Armored Scale Insects
UCIPM lists greedy scale
(Hemiberlesia rapax) as a pest of
ornamental persimmons. 7 Eberling states
that latania scale (Hemiberlesia lataniae) is
sometimes seen, “especially under the
sepals of the fruits” 3 . I occasionally see
Hemiberlesia, but they have never been
serious.
Hemiberlesia scale on green fruit.
Soft Scale Insects
UCIPM lists European fruit lecanium scale as a pest of ornamental
persimmons. 7 This scale is very common in persimmon orchards. I also
often see the closely related frosted scale. I have seen brown soft scale on
one a couple of occasions. Eberling also mentions black scale (Saissetia
oleae) on persimmon. 3
European fruit lecanium scale
Parthenolecanium corni
Frosted scale
Parthenolecanium pruinosum
These two soft scales look very
similar, and have identical life histories,
so they can be treated as one pest,
Parthenolecanium. They damage fruit Lecanium scale egg sacs on twig.
by depositing honeydew which fosters
black sooty mold.
On some hosts such as pistachios, Parthenolecanium reportedly has one
generation per year, but on grapes and persimmons in the San Joaquin
Valley there are two generations. They overwinter partially grown, and
begin reaching maturity as egg sacs in late March or early April.
The first eggs typically hatch during the first two weeks of May, and
most of the new crawlers move to leaves. Early June, when all are hatched

and the majority is exposed, is the best spray timing. Most of the honeydew
is produced by the larger instars during the last half of June and early July.
Second generation egg sacs begin to appear near the end of June, and the
eggs begin hatching some time in July, producing the crawlers that will
eventually overwinter.
Parasites are
capable of maintaining
Parthenolecanium
populations at
acceptable levels.
Presumably the
parasites are the same
as in grape:
Coccophagus
scutellans, which
Frosted scale near maturity.
attacks small stages of
scale, C. lycmnia,
found in second and third stage scale, and Metaphycus luteolus, with
multiple adult emergences from third state scale (pers. comm. Kent Daane).
The parasites can be disrupted by ants or pesticides, leading to more serious
damage.
Applaud, when it gets registered, should
work very well in an early June application.
Imidacloprid is reasonably effective, but is
disruptive to parasites of both soft scales and
mealybugs. Movento has not tested well on
soft scales in other crops.
Brown soft scale
Coccus hesperidum
I occasionally see a few brown soft scale
in persimmons. In citrus and pomegranates
this scale is potentially a serious pest but is
usually controlled by parasites. It has
multiple overlapping generations. A June
timing with Applaud, when it is registered,
should provide control.
Brown soft scale:
Near maturity on a twig (above);
Nymph on a sepal (below).

White Flies
California Rare Fruit Growers mention whiteflies on persimmon. 1 I have
not seen them. They could be controlled by Movento or by Applaud when it
is registered.
Beetles
UCIPM lists flatheaded borers (Buprestidae) and Fuller rose beetle
(Asynonychus godmani) as pests of ornamental persimmons. 7 I have not seen
them in orchards.
In Eastern United States the twig girdler, Oncideres cingulata, is an
important pest of the indigenous American persimmon. 3 The flatheaded
appletree borer, Chrysobothris femorata, mainly attacks young trees
unprotected from sunburn. 3
Thrips
California Rare Fruit Growers mention that thrips can cause skin
blemishes on fruit. 1 I have not seen them.
Mites
The persimmon bud mite (Aceria biopsidia) causes a condition known as
brown lace collar. 7 “This species occurs under fruit buttons and under buds
scales on cultivated persimmon in southern California. Mites blacken the
fruit surface and stem under fruit buttons, and evidently are implicated in
premature dropping of fruit.” 4 This mite is presumably the reason that
several miticides are registered in persimmons.
Japanese researchers report that bud mites hibernate inside dormant buds
and become active in March. After budbreak, they stay under the bud scales
until the end of April. In May, they move to leaves, mainly next to midribs
where trichomes provide cover. Some also enter axillary buds where they
remain until winter. After petal fall, bud mites infest fruit under the calyx.
Peak infestation is in middle to late July. The best time to spray in Japan is
in May. 5
So far I have not seen brown lace collar in the San Joaquin Valley.

References
1. California Rare Fruit Growers. 1996. Persimmon Fruit Facts.
http://www.crfg.org/pubs/ff/persimmon.html.
2. Dentener, Peter R., Philip J. Lester and Allan B. Woolf. 1995. A report
on effective disinfestation of persimmon pests while reducing chilling
injury. Persimmon Profile, Journal of the Persimmon Industry Council,
December 1995 pg 8.
http://www.hortnet.co.nz/publications/science/per1.htm.
3. Ebeling, Walter. 1959. Subtropical Fruit Pests. Univ. Calif. Div. Agric.
Sci.
4. Jeppson, L. R., H. H. Keifer, and E. W. Baker. 1975. Mites Injurious to
Economic Plants. Univ. Calif. Press.
5. Katsumi, H., & I. Katsunori. 2002. Biology of the persimmon bud mite
(Aceria diospyri Keifer) and its control by pesticides. Bull. Yamaguchi
Agri. Exp. St. 53: 65-72.
6. LaRue, J.H., K.W. Opitz, and J.A. Beutel. 1982. Growing Persimmons.
Univ. Calif. Div. Agric. Sci. Leaflet 21277.
7. UC IPM Online. How to manage pests in gardens and landscapes:
persimmons.
http://www.ipm.ucdavis.edu/PMG/GARDEN/PLANTS/persimmon.html
8. UC IPM Online. Pistachios.
http://www.ipm.ucdavis.edu/PMG/selectnewpest.pistachios.html