Sporadic or minor pests and disorders: budbreak through bloom

  • Darkling beetles
  • Thrips (onion, western flower thrips)
  • Western tussock moth caterpillar
Disease and abiotic disorders
  • Armillaria root rot
  • Delayed leafing
  • Frost damage
  • Wood decay fungi mushrooms
Click on photos to enlarge. Names link to more information on identification and management.
Invertebrates and damage
Darkling beetle adult.

Darkling beetle adult

Identification tip: Adults are dull bluish black or brown beetles that chew off seedlings or feed on foliage. Be careful to distinguish from predaceous ground beetles, which are shinier and may have colorful markings.

Feeding damage on dormant pistachio bud caused by darkling beetle, Blapstinus sp.

Darkling beetle bud damage

Identification tip: Darkling beetle chewing damage kills pistachio buds.

Adult western flower thrips.

Thrips (onion, western flower)

Identification tip: Adults are minute, slender insects with feathery wings and vary from pale yellow to brown. Western flower thrips (shown here) are slightly larger than onion thrips and have red eyes and 8-segmented antennae, while onion thrips have gray eyes and 7-segmented antennae.

Western tussock moth larva.

Western tussock moth caterpillar

Identification tip: Mature caterpillars are large with numerous red and yellow spots and long tufts of hair. Contact with larvae may result in dermal irritation caused by irritating hollow bristles connected to poison sacs under the larval skin.


Disease and abiotic disorders
Clusters of Armillaria mushrooms.

Armillaria root rot (oak root fungus) mushrooms

Identification tip: Short-lived mushrooms often grow around the base of Armillaria-infected trees during wet periods.
Fruiting bodies of a wood rot fungus, Ganoderma sp., growing at the base of a tree trunk.

Ganoderma spp. wood rot fungus

Identification tip: Fruiting bodies grow at the base of tree trunks.
Basidiocarps of the wood rotting fungus, Schizophyllum commune.

Schizophyllum spp. wood rot fungus

Identification tip: Fruiting bodies grow on tree bark.

Photo not available

Delayed leafing

Identification tip: Unusually cold temperatures in late November and early December can result in delayed budbreak.
Shriveled and wilted pistachio leaves caused by spring frost.

Frost damage

Identification tip: Leaves respond to spring frost by shriveling and wilting.

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