Hazelnut-Filbert bud mite

Filbert bud mite (Phytocoptella avellanae)

Cecidophyopsis vermiformis

Pest description and crop damage Also known as big bud mite, these microscopic eriophyid mites feed on and within leaf and flower buds and catkins. Buds swell to large size (blasted buds) before they die and fall off. Bud mites are a big problem in some legacy hazelnut varieties, especially Ennis, Daviana and Royal. The OSU hazelnut breeding program selects against bud mites so blasted buds are relatively rare in recent cultivar releases. However, severe infestations have been noted in Lewis, Clark, Casina, Yamhill, and McDonald cultivars. Infested buds do not produce nuts and can cause vegetative growth abnormalities.

Pest monitoring Time sprays to intercept mites as they migrate from blasted buds to new buds in early spring. Sprays applied at the peak migration timing will be most successful. Recent research suggests the peak migration typically occurs from late March/early April to mid-May in the Willamette Valley. Monitoring is accomplished by placing double-sided sticky tape or tacky insect glue on branches below blasted buds and counting trapped mites under magnification at regular intervals. Most materials labeled for bud mite cannot be applied by air.

Management-biological control

Releases of predatory mites (Galendromus spp.) is impractical in commercial settings but may be effective for home use. Predatory mites cohabitate in blasted buds with bud mites. Mite flaring may be linked to use of broad-spectrum insecticides and loss of biological control predatory mites. Note that predatory mites also help keep spider mites under control.

Management-chemical control: HOME USE

No products are registered for home use for this pest.

Management-chemical control: COMMERCIAL USE

  • abamectin (Abamectin 0.15 EC) at 10 to 20 oz/a. PHI 21 days. REI 12 hr. Do not exceed two applications per season.
  • calcium polysulfide (Sulforix) at 3 gal/a. REI 2 days.
  • fenpyroximate (Fujimite XLO) at 2 to 4 pints/a in minimum of 100 gal water. No more than two applications per season.
  • lime-sulfur (BSP) at 12 gal/a. REI 2 days.
  • micronated sulfur
    • Kumulus DF at 5 to 25 lb/a in 50 to 400 gal water. See 24(c) SLN label. Do not apply when air temperatures will exceed 90°F within 3 days of application. REI 24 hr.
    • Microthiol Disperss at 10 to 20 lb/a in 50 to 400 gal water. See 24(c) SLN label. Do not apply when air temperatures will exceed 90°F within 3 days of application. REI 24 hr.
  • pyridaben (Nexter) at 2.67 oz/100 gal water (10.67 oz/a). PHI 7 days. Do not exceed two applications per season.
  • spirodiclofen (Envidor 2SC) at 16 to 18 fl oz/a. PHI 7 days. REI 12 hr.
  • tolfenpyrad (Bexar) at 27 oz/a. PHI 14 days. REI 12 hr. See 2(ee) label for hazelnut (OR/WA only).