| Scientific Name | Specimen Records |  Click photo to enlarge. Photo by L. Ted Grannan, Jr. |
|||
| Aceria cinereae (Keifer) | ATBI Database | ||||
| Common Name | |||||
| Butternut Leaf Eriophyid Mite Gall Maker | |||||
| Kingdom | Phylum | Class | Order | Family | |
| Animalia | Arthropoda | Arachnida | Acarina | Eriophyidae | |
| Animals | Arthropods | Arachnids | Mites | Eriophyid Mites | |
Light green puckering to yellowish felt-like growths (erineum galls) on a butternut leaf (Juglans cinerea) usually indicates the presence of the almost microscopic eriophyid mite, Aceria cinereae (Keifer) (Johnson and Lyon 1991). The mites also feed on the nut husk, causing a russeting of its surface.
Other species of eriophyid mites on other host plants provide an alternate food source for predatory mites used in the control of more serious crop pest mites, a characteristic that was exploited early in the development of the field of Integrated Pest Management by Dr. Stan Hoyt of Washington State University (Murray, 2002). Having an alternate food source allows predatory mite populations to remain high when the pest species populations crash, keeping the pest population under control. The range of this mite is probably the same as that of its host.
SPECIES DESCRIPTION
Physical Characteristics:
The presence of this mite creates erinea on both surfaces of the butternut leaf (Juglans cinerea). On the top leaf surface the area containing the erinea becomes swollen and the tissue more dense. The erinea on the undersides of leaves are in depressions that fit between the lateral veins. As the leaf and the erinea age, the erinea darken and by late August may be nearly black. Heavily infested leaves are twisted or otherwise distorted, often falling off the tree. When leaflets are covered with these galls, their effectiveness as food producers is greatly diminished. The mites also feed on the nut husk, causing a russeting of its surface. Specific characteristics of the mite itself are unknown from the Smokies.
DISTRIBUTION
Global
Known only from the butternut (Juglans cinerea), which is only native to parts of eastern North America.North America
These mites, Aceria cinereae, are probably distributed throughout the range of their host plant (Johnson and Lyon 1991).Park
Aceria cinereae has been noted only from population near Big Cove Road near Cherokee, North Carolina. It is presumed that this species would be found anywhere its host is found.
NATURAL HISTORY
Habitat
Many eriophyid mites spend their winters under bark scales and in their host tree buds. It can only be conjectured that Aceria cinereae (Keifer) does this as well. In early spring some species of eriophyid mites migrate to unfurling buds and leaves to begin feeding. Aceria cinereae appears to feed only upon butternut (Juglans cinerea), an early successional species of flood planes and riparian zones. So far, records of this eriophyid are limited to the Butternut Grove located in North Carolina near Big Cove Road.
Reproduction
Little is known about the reproduction of Aceria cinereae although it probably follows a similar pattern to the following eriophyids Some species can lay up to 80 eggs over a month’s lifetime, which develop over 1-2 weeks through two developmental stages ( Murray, 2002). Where sexual reproduction occurs, males leave sperm sacs are the leaves for the females to encounter (Murray 2002).
The reproductive process of Phyllocoptes exchordae (Keifer) appears to be representative of many eriophyids. Eggs are elliptical and bright orange-red when first lain, becoming darker as hatching time approaches. Females congregate in sheltered places on the host plant to over-winter. Males occur, but parthenogenic reproduction seems to be the rule.
Pear and apple blister eriophyids over-winter under bud scales and migrate to the leaves in spring. Mites feed on undersurfaces of the leaves. The epidermis ruptures where feeding occurs and mites enter the opening to deposit eggs. As eggs hatch, more and more mites destroy increasing numbers of cells. A pimple-shaped swelling appears on the upper surface and develops into a blister, enlarging and coalescing with other blisters, discoloring large continuous patch on the leaves. As internal leaf tissue deteriorates, infested areas become brown or black, then shrink and die out. (Johnson and Lyon 1991)
Longevity
Unknown.
Ecology
Aceria cinereae appears to feed only upon butternut (Juglans cinerea) creating felt-like erinea on the leaf. As activity increases through the spring and early summer, more and more erinea are produced by the tree in response to the eriophyids. As the erineum dries, activity lessens. Although not specifically known for Aceria cinereae, other related eriophyid mites migrate to protected areas of the tree becoming less active through the remainder of the summer, over-wintering in bark fissures and bud scales of the host tree.
Associated Species
Host: Butternut (Juglans cinerea). According to Johnson and Lyon (1991) numerous species of predatory mites have been associated with eriophyids, most commonly, Seius species. They not only feed on leaf vagrants and erineum mites but frequently enter galls to prey upon mites as they develop inside. Eriophyid mites also may depend on birds and flying insects, as well as wind, for dispersal (Murray 2002).
CONSERVATION BIOLOGY
Special Protection Status
Rangewide: None.
In Park: All animals, including insects and other arthropods, are protected within the Great Smoky Mountains National Park. Collection requires a permit, which are typically only issued for educational or research purposes.
Management Concerns
Butternut trees, throughout their range are becoming scarce due to the infestation of Sirococcus clavigignenti-juglandacearum, a fungus most likely introduced from outside North America. The fungus initially infects trees through buds, leaf scars, and possibly insect wounds and other openings in the bark, rapidly killing small branches. This is sure to have an effect upon the viability of this mite. Likewise, the combination of damage from mites and fungus may be more detrimental to the host tree than either alone.
ACKNOWLEDGEMENTS
Field Work
Jessie Smith, Jordan Lezard, and L. Ted Grannan, Jr., National Park Service.
Maps
N/A
Photographs
National Park Service photo by L. Ted Grannan, Jr.Supporting Institutions
We wish to thank the Burroughs Wellcome Fund for supporting the interns and the Burroughs Wellcome Fund funded Park Service Employee who conducted the work upon which this page is based.
Text
L. Ted Grannan, Jr. Biological Science Technician, Purchase Knob Appalachian Highlands Science Learning Center, Great Smoky Mountains National Park.
Web page
REFERENCES
Johnson, W. T. and Lyon, H. H. 1991. Insects That Feed On Trees and Shrubs. Comstock Publishing Associates, Cornell University Press, Ithaca, NY and London
Murray, Todd. 2002. Eryophyid Mites. Garden Friends and Foes. Washington State University Whatcom County Extension web site: whatcom.wsu.edu/ag/homehort/pest/eriophyd.htm
USDA, US Forest Service Bulletin HT-70, 1996, How to Identify Butternut Canker and Manage Butternut Trees
