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Eriophyid mite

Eriophyidae

53 host plants

Last updated

Data Coverage 3 of 6 dimensions
Host Plants
GDD Threshold
Peak Activity
Damage Severity
Monitoring
Regional Notes

Eriophyid mites are microscopic arachnids that feed on pine, fir, and other conifer foliage, causing discoloration, distortion, and abnormal growth of needles. You will see affected needles appear stunted, curled, or develop unusual coloring without visible pest activity. Damage accumulates on new growth in spring and early summer. Heavy infestations can reduce tree vigor and cause branch dieback.

Most trees tolerate eriophyid mite damage without serious decline. No effective chemical control is practical for landscape trees. Maintain tree vigor through adequate watering and avoid drought stress that makes plants more susceptible. Prune out severely affected branches if damage is severe. Natural predatory mites and other beneficial arthropods usually keep eriophyid mite populations in balance without intervention.

Quick Reference

Order
Acari
Type
mite
Host Plants
53
Peak Activity
March-May: Bud swell and emergence; gall initiation begins. May-June: Peak ga...

Monitoring & Action

How to Monitor

Dormant season: Inspect buds and bark for overwintering populations (low priority for cosmetic damage). March-May: Scout for early gall formation on new growth. Once galls are visible, treatment is ineffective - mites are protected inside gall tissue. Accept cosmetic damage on healthy landscape plants.

When to Act

For most landscape plants: no action threshold. Galls are cosmetic and plant health is unaffected. Exception: Fuchsia gall mite (Aculops fuchsiae) causes severe branch deformation on show plants - warrants management. Threshold decision: cosmetic tolerance vs. treatment cost.

What Damage Looks Like

Adults of eriophyid mites cannot be seen without magnification. Pearleaf blister mites are light in color, cylindrical, tapered at the posterior end, with two pairs of short legs at the front of the body. The overall appearance is that of a small worm. Nymphs have the overall appearance of the adult, but are even smaller. Adult rust mites are wedge-shaped and yellowish brown with two pairs of legs near the front of the body. Pearleaf blister mite feeding on leaves causes reddish to yellowish...

Cultural Controls

  • For ornamental plants with cosmetic galls: monitor and accept damage. No treatment necessary for 99% of landscape host plants. For fuchsia gall mite specifically: prune heavily infested growth aggressively; choose resistant cultivars (species fuchsias more resistant than hybrids).

Host Plants (53)

Agathis australis Kauri Tāne Mahuta, Kauri Pine Araucaria araucana Monkey Puzzle Tree, Chilean Pine Araucaria bidwillii Bunya Pine Araucaria cunninghamii Hoop Pine, Moreton Bay Pine Araucaria heterophylla Norfolk Island Pine Athrotaxis laxifolia Tasmanian Pencil Pine, Summit Cedar Cephalotaxus harringtonia Japanese Plum Yew, Cow's Tail Pine Glyptostrobus pensilis Chinese Swamp Cypress, Water Pine Water Fir Shui song Microcachrys tetragona Creeping Pine, Creeping Strawberry Pine Pinus albicaulis Whitebark Pine, Scrub Pine, White Pine Pinus aristata Bristlecone Pine, Rocky Mountain Bristlecone Interior Bristlecone Pinus attenuata Knobcone Pine Pinus banksiana Jack Pine, Scrub Pine, Banksian Pine, Hudson Bay Pine Pinus bungeana Lacebark Pine, Whitebark Pine, Baipi Song Pinus canariensis Canary Island Pine Pinus cembra Swiss Stone Pine Pinus contorta Lodgepole Pine Pinus contorta var. contorta Shore Pine Pinus contorta var. latifolia Rocky Mountain Lodgepole Pine Pinus coulteri Coulter Pine, Bigcone Pine Pinus densiflora Japanese Red Pine Pinus edulis Pinyon Pine, Piñón Pine, Two-needle Pinyon Colorado Pinyon Pinus elliottii Slash Pine, Swamp Pine Pinus flexilis Limber Pine, Rocky Mountain White Pine Pinus halepensis Aleppo Pine, Jerusalem Pine Pinus heldreichii Bosnian Pine, Snakeskin Pine Pinus jeffreyi Jeffrey Pine, Western Yellow Pine, Bull Pine Pinus kwangtungensis Kwangtung Pine, Guangdong Pine Pinus lambertiana Sugar Pine Pinus leucodermis Bosnian Pine Pinus monophylla Singleleaf Pinon Pine, One-leaved Pine Pinus monticola Western White Pine Pinus mugo Mugo Pine Pinus mugo var. pumilio Mugo pine, Dwarf Mugo pine Pinus nigra Austrian Pine Pinus parviflora Japanese White Pine Pinus parvifola Pinus parvifola Pinus pinaster Maritime Pine, Cluster Pine, Turpentine Pine Pinus pinea Italian Stone Pine, Umbrella Pine Pinus ponderosa Ponderosa Pine, Western Yellow Pine Pinus pumila Japanese Stone Pine, Dwarf Siberian Pine Pinus radiata Monterey Pine Pinus resinosa Red Pine Pinus sabiniana Gray Pine, Foothill Pine Pinus strobiformis Southwestern White Pine, Mexican White Pine, Chihuahua White Pine Pinus strobus Eastern White Pine Pinus sylvestris Scots Pine, Scotch Pine Pinus thunbergii Japanese Black Pine Pinus virginiana Virginia Pine, Scrub Pine, Jersey Pine Pinus wallichiana Himalayan Pine, Bhutan Pine Pinus yunnanensis Yunnan Pine Sciadopitys verticillata Japanese Umbrella Pine, Umbrella Pine Wollemia nobilis Wollemi Pine