Aculops fuchsiae: FUCHSIA GALL MITE
-an eriophyid mite/spider family
BACKGROUND
Fuchsia gall mite (Keifer) from Brazil was first described in 1972. In
1981 fuchsia mites appeared in California where they spread rapidly and
decimated the fuchsia industry. By 2003, growers in Brittany, France,
had infestations.
In the Pacific Northwest, fuchsia gall mite has infested plants
intermittently over the past ten years. Then in 2004 & 2005, serious
infestations were found in gardens from Tacoma to Portland, presumably
because of warm winters. By the summer of 2006, no damage was found on
any winter hardy fuchsias in the gardens.
The Northwest Fuchsia Society (NWFS), primarily in Western Washington &
Oregon, USA, compiled and distributed information on fuchsia gall mite
and how to minimize the problem-- before it gets out of hand. Using
California’s 20+ years of experience and with input from Northwest
growers, we will be able to deal effectively if a gall mite problem
occurs again in our yards and greenhouses. Our information will be
updated as we learn more.
RECOGNIZING FUCHSIA GALL MITE
Aculops
fuchsiae, an eriophyid mite, cannot be seen with the naked eye, and
these mites multiply rapidly. They affect
only fuchsias and are not to be confused with ‘spider mite’. The mites
live and reproduce within the folds of galled tissue
and among plant hairs. Without a 40+x microscope, their presence can be
identified only by the grotesque damage
that they do:
>Plant parts (leaves, flowers, stems) are fused together, twisted, &
swollen, forming galls. .
>Infected areas may look hairy with reddish and whitish areas.
Early detection- leaves thicken, redden, become hairy, & chunky galls
and lumps appear. Gardeners suspecting fuchsia gall mite should cut off
an affected part of the plant, place it in a Zip Lock bag, and seek
assistance from a local fuchsia group. Do not assume that because some
leaves are curled or unhealthy (aphids and other insects can cause
this!) that the plant has gall mite.
Photos- Larry Mason
The life-cycle of Aculops fuchsiae is 2-4 weeks with four stages: egg,
larva, nymph, adult. The females lay ~50 eggs at one time, and in 1-2
weeks, they hatch. (If half of those 50 eggs are female, in no time at
all, there are hundreds!) The wee mites are expert at hiding in plant
structures to avoid danger, and controlling them is difficult but not
impossible.
Dispersal of fuchsia gall mites is done by the wind, insects, birds and
especially by gardeners handling an infected plant and moving on to
another-- with the mites hitchhiking on hands, clothes, hair…
PREVENTION & CONTROLS
BIOLOGICAL CONTROLS: Aculops fuchsiae has predators, some believed to
have been helpful in California, but these predators cannot get to all
of these elusive, wee fuchsia mites. Control potential here is limited.
CLIMATIC CONTROLS: With 7 nights of temperatures in the teens and low
20's in the winter of 2006, the climatic control potential in Western
Washington and Oregon has become better known. Presumably, the NWFS has
found a minimum range of temperature under which gall mites cannot
survive. We now know that infestations in gardens with fuchsias that are
outdoors all winter is a ‘warm winter’ problem.
CONTROL BY FUCHSIA GROWERS: How fuchsia growers raise their fuchsias has
an enormous effect on spreading fuchsia mite. Advice from the American
Fuchsia Society (AFS) based in San Francisco, suggests 3 approaches:
1. Destroy fuchsia mite infected plants. New starts are inexpensive.
They should be purchased from fuchsia specialists who are aware of the
problem and have a program to avoid it. Then…
2. Raise Gall Mite Resistant and Immune fuchsias. Like with most pests,
mites are attracted to some fuchsias, but not to all. Brazilian
fuchsias, where the mite originated, have developed resistance. Mites
may be present, but damage is minor. Several species are resistant and
pass that trait on to their offspring. Some fuchsias are even immune.
Hybridizers in California are raising new cultivars specifically for
their gall mite resistance. They are appearing in PNW fuchsia nurseries.
3. If mite damage appears: Prune out the damage to the plant parts.
Use chemical controls- choices listed below.
Prevention- start chemical controls in dormancy just BEFORE the new
leaves
p; appear. Saturate the plant & soil. To be successful, you need to be
persistent,
and follow directions carefully.
For the dormant period (fall & winter) prune plants severely (See
sketchà).
Deeply planted hardies may be pruned even harder. Remove the leaves,
young
stems & most leaf nodes, galls, & loose bark where the mites reproduce,
feed and
over-winter. Clean up underneath the plants. Give fuchsia mites as
little area as
possible to live on and hide in.
During the plant’s growth periods (spring & summer), cut out the mite
infected area- cut two nodes below it.
Develop a spraying program to delay more mites hatching (see below) & to
keep plants healthy.
>In general, establish a program to keep plants healthy; stick to it so
that you don’t spread mites to neighbors and
reinfect your own plants.
>Do not work on an infected plant and then go to one not infected. YOU
will just spread the mite.
>In handling infected plant material, wear disposable gloves, burn the
plant material or place it in a plastic bag,
tie it up snuggly, and put it and the gloves in the garbage. Do NOT
compost or recycle it.
>Shower and change your clothes before you work on clean plants—don’t
let the mites hitchhike on you!
>Disinfect tools and containers.
>If possible, isolate infected plants and keep animals away; they could
also carry mites to other fuchsias.
CHEMICAL CONTROLS:
IMPORTANT- Whatever chemical controls you use…
1. Choose products specified for Aculops fuchsiae/fuchsia gall mite or
eriophyid mites & safe
for fuchsias or ornamental plants. Notice whether it’s an indoor or
outdoor product. Names
of pesticides can be similar and confusing. Read the label!
2. Read the directions carefully and follow them so that plants are not
re-infected.
3. Read and follow the safety precautions. Some products are toxic to
humans and other animals.
CONTACT SPRAYS- Partial/Temporary Control
After pruning and cleaning up infested plants, contact sprays can help
control mites. Saturate the plant because light applications will build
immunity. With contact sprays you want to get the new hatchlings, so
remembering the life cycle, three applications, 7-10 days apart are
needed- or as directed for fuchsia mite on the product.
Contact sprays include horticultural oils and soaps which smother the
mites (as well as other pests) like Safer Oil & Ultra Fine Oil (by
Sunspray), Volck Oil (by Chevron), Hot Pepper Wax…
To be most effective, use with a ‘spreader sticker’.
Control potential is limited with contact sprays; plants may be
re-infected.
If you have had serious gall mite damage and/or have many fuchsias, you
may choose stronger products with active ingredients that kill fuchsia
mites. They have a much higher control potential, are relatively safe
when correctly used and are longer lasting. For example- Bayer Advanced
Complete Insect Killer & Garden Tech’s Sevin Bug Killer. (The active
ingredient is carbaryl- hazard to bees and aquatic life. Keep away from
standing water; remove any blossoms that may attract bees. Spray
outdoors and let dry if bringing back indoors.)
SYSTEMICS- The Most Effective Control
Most effective are outdoor products with systemic qualities, but again,
there are hazards to consider. Examples: Ortho Systemic Insect Killer
(formerly Isotox- Concentrate- For fuchsia mite, Ortho recommends 3
times; 4 days apart) & Orthenex Garden Insect & Disease Control.
Commercial nurseries have access to products not available to the
public. Ron Monnier, of Monnier’s Country Gardens in Woodburn, Oregon,
has an effective spraying program and has had no gall mite.
For further details- Ron at mcg@web-ster.com-
www.monnierscountrygardens.com
SOURCES:
Dr. Carlton Koehler, et al, entomologist, Urban Pest Management, U. of
California, AFS Bulletin, Aug., 1985.
AFS Bulletins- 1982-2005;
American Fuchsia Society- www.americanfuchsiasociety.org;
European Plant Protection Org.- www.eppo.org;
Texas A & M Extension Service- www.tamu.edu;
Bayer, Ortho, & Sunspray product labels.
NWFS Gall Mite Committee- Salli Dahl, dahlhaus@myhome.net; Frankie
Dennison, rldmfd@earthlink.net; Ron Herzog, ronh@americanrooftop.com ;
Gwen Jensen, gjensen11@juno.com; Jackie LaVerne-Crossman, fuchsiagypsy@comcast.net;
Ron Monnier, mcg@web-ster.com; Jay Siegel, jazfuchsias@prodigy.net.
March, 2006
