1. Mites - Their Groups, Diagnosis, and Control
Ornamentals Pests:
Mites - Their Groups, Diagnosis, and Control
David J. Shetlar, Ph.D.
The “BugDoc”
The Ohio State University,
OARDC & OSU Extension
Columbus, OH
© July, 2007, D.J. Shetlar, all rights reserved

2. Main Mite Groups
Spider Mites (Tetranychidae) – Oligonychus, Tetranychus, Panonychus, Eurytetranychus, Eotetranychus, Bryobia.
False Spider Mites (Tenuipalpidae) – Brevipalpus
Eriophyid Mites (Eriophyidae) – bud, gall, rust mites.

3. Other Mite Terms
Cool-season Mites – most active in spring and fall seasons, when temperatures are above freezing but blow 80F during the day.
Warm-season Mites – Seem to do best during summer warm periods, also do well in drought.
Gall Mites – cause plant distortions or abnormal growths.
Rust Mites – cause general yellowing or bronzing of the foliage, but mites are almost too small to see.

4. Bryobia spp.
Clover mite (B. praetiosa) – cool-season grass and weed feeder.
Honeysuckle bryobia (B. lonicerae) – common on shrub honeysuckle

5. Panonychus spp.
European red mite (P. ulmi) – warm-season mite on fruit trees and Crataegus.
Adult female
Stippling of apple leaf.

6. European red mite (P. ulmi) – warm-season mite on fruit trees and Crataegus.
Adults ballooning
Overwintering egg clusters
(dormant oils?)

7. (dozen species, yellow to green)
Eotetranychus spp.
(dozen species, yellow to green)
Honeylocust mite (E. multidigituli) – warm-season on leaf undersurfaces.

8. (dozen species, yellow to green)
Eotetranychus spp.
(dozen species, yellow to green)
Linden mite (E. tiliarium) – warm-season on leaf undersurfaces.

9. Tetranychus spp.
Twospotted spider mite (T. urticae) – warm-season mite of greenhouses, annuals and perennials, winged euonymus and some Viburnum.

10. Twospotted spider mite (T. urticae) –

11. (many species, dark red, brown or green)
Oligonychus spp.
(many species, dark red, brown or green)
Spruce spider mite (O. ununguis) – cool-season conifer feeder.
Southern red mite (O. ilicus) – cool-season, attacks broadleaf evergreens.
Oak spider mite (O. bicolor) – warm-season, upper leaf surface.
Maple spider mite (O. aceris) – warm-season, lower leaf surface.
O. newcomeri – warm-season, Amelanchier leaves.

12. Spruce spider mite (O. ununguis) – cool-season conifer feeder.
Bronzing of spruce
Mites & webbing on fir

13. Spruce spider mite (O. ununguis) – cool-season conifer feeder.

14. Spruce spider mite populations (thick line) over the 1993 season in Columbus, OH. Note that the population of active mites disappears in early July due to several days with temperatures above 29°C (=86°F), a characteristic of a cool-season mite.

15. Southern red mite (O. ilicus) – cool-season, attacks broadleaf evergreens.

16. Oak spider mite (O. bicolor) – warm-season, upper leaf surface.

17. Oak spider mite (O. bicolor) – warm-season, upper leaf surface.

18. Maple spider mite (O. aceris) – warm-season, lower leaf surface.

19. False Spider Mites – Tenuipalpidae
Privet mite (Brevipalpus obovatus) – warm-season, flat mite numerous hosts.
Phaelenopsis mite, another false spider mite.

20. Eriophyid Mites
Rust Mites – free-living “vagrants” on foliage surface, causing yellowing and russeting of foliage.
Gall Mites – Cause abnormal plant growths, bladder and spindle galls, and erineum.
Bud Mites – bud rosettes, new growth distortion, “blasted” buds.

21. Eriophyid Mite Characteristics
Two pairs of legs
Small!
Able to flip into air to balloon!

22. Hemlock rust mites.

23. Privet rust mites.

24. White pine rust mites.
Spruce rust mites.

25. Baldcypress rust mites.

26. Maple bladdergall and spindlegall mite damage.

27. Maple erineum galls.

28. Pear leafblister mite damage.
Pear leafcurl mite damage – a different species!

29. Ash flowergall mite damage to flower buds

30. Ash flowergall mites “questing” for air currents to balloon!

31. Coneflower Rosette Mite

32. Pine Rosette Mite

33. Juniper tip-dwarf mites.

34. Miticides Alternatives Traditional Avid (all mites!) Kelthane
Hexygon (eggs & larvae only, spider mites only)
Floramite (spider mites only)
Sanmite (spider mites only)
Forbid (all mites!)
Conserve
Pyrethroids – NO!??
Soaps or Oils
Traditional
Kelthane
Morestan
Cygon
Orthene ? (Professional only)
Sevin (eriophyids only) X X ??

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