Pest profile

White Peach Scale

Pseudaulacaspis pentagona · Hemiptera: Diaspididae[3]

White peach scale is one of the most commonly seen scales on peaches, and it can kill limbs and whole trees.[1]

White peach scale, crowded white armored scale covers encrusting tree bark
White peach scale, crowded white armored scale covers encrusting tree bark. (c) ncb1221, some rights reserved (CC BY) — via iNaturalist, CC BY 4.0

How to identify it

  • Adult females are 1/16 to 1/8 inch across, circular and yellowish to grayish white with a yellow or reddish spot.[1]
  • It infests bark, fruit and leaves of peach trees.[1]

Look-alikes

Look-alikeHow to tell them apart
San Jose scaleGives birth to live crawlers and has four to six generations a year rather than three.[1]
Japanese maple scaleA white look-alike armored scale with a purple insect underneath.[2]

Where it lives

HGIC covers it on peach trees in South Carolina.[1]

US map: public records from 14 states since 1990 (GBIF).

Biology and life cycle

It overwinters as adult females, which start laying eggs in early April; males live about a day.[1]

Crawlers spread along branches for a few days before settling; there are three generations a year.[1]

Damage and signs

  • Infestations cause stunting, leaf drop and death of branches and potentially entire trees.[1]

Health risk

It feeds on plants; Clemson HGIC mentions no risk to people.[1]

Control

Pesticides

Horticultural oil applied before budbreak, above 40 degrees F, smothers overwintering females.[1]

Common questions

What is the white crust on my peach tree branches?
It may be white peach scale, which can coat bark with white covers.[1]
When should I spray oil for peach scale?
Before budbreak in the dormant season, when it's above 40 degrees F.[1]

Sources

  1. Clemson Cooperative Extension, Home & Garden Information Center, “Peach Insect Pests (HGIC 2210).” hgic.clemson.edu/factsheet/peach-insect-pests/ (accessed 2026-10-06)
  2. University of Kentucky Entomology (ENTFACT), “Managing Japanese Maple Scale in Kentucky Nurseries (ENTFACT-463).” entomology.mgcafe.uky.edu/ef463 (accessed 2026-10-06)
  3. iNaturalist, “Pseudaulacaspis pentagona taxon page (order and family).” www.inaturalist.org/taxa/716067 (accessed 2026-10-06)

Updated 2026-10-14. Built from sourced records. Spot an error? Tell us.