Scale crawlers, updated 2026 scouting guide, IPM webinars, Box tree moth

Educational Resource Update: 

Stay informed

  • Sign up for the 2026 – Rutgers Ornamental IPM Program – click here to sign up
  • Program is free, but registration is required – Registration includes:
    • Site visit to your ornamental nursery/farm from Rutgers agents
    • Delivered printed IPM resources (Guides, factsheets, bulletins)
    • Free pheromone & sticky trap kit + guidance on setup/monitoring (for commercial nursery/greenhouse and Christmas tree farms)
    • Access to live bi-weekly webinars (Zoom)
    • (Next session – TUESDAY 6/9 @ 12PM) – Guest Speaker Dr. Richard Cowles – Connecticut Ag Exp. Station – Scale Management 
    • Every Second and Fourth, Tuesday, April through September
  • Visit the Rutgers Ornamental IPM Website Rutgers Ornamental IPM Website (click here) for updated webinar videos.

Scale crawler emergence predictions throughout NJ. 

Now is an excellent time to be scouting for crawler emergence using double sided (or doubled over – sticky side out) tape. Targeting scale insects is most successful during their crawler periods, however this should be visually confirmed for greatest efficacy. For more information on installing this type of IPM trap and others please see – Setting up and deploying IPM traps – Tutorial Video 2026 (click here).

Common Name GDD RANGE Target Stage SOUTH – Upper Deerfield (NJ50) CENTRAL – Howell (NJ10) NORTH – Randolph NJ (AU137)
MIN MAX START STOP START STOP START STOP
Cottony camellia / taxus scale (soft) 520 Crawlers (only) 17-May 20-May 18-May
Euonymus scale 533 820 Crawlers (Gen 1) 18-May 3-Jun 21-May 8-Jun 18-May 7-Jun
*Cryptomeria scale 600 800 Crawlers (Gen 1) 20-May 2-Jun 27-May 7-Jun 24-May 6-Jun
*Sprucebud scale (soft) 700 1150 Crawlers (only) 27-May 18-Jun 2-Jun 24-Jun 30-May 25-Jun
White prunicola scale 707 1151 Crawlers (Gen 1) 28-May 18-Jun 2-Jun 24-Jun 30-May 25-Jun
*Juniper scale 707 1260 Crawlers (Gen 1) 28-May 18-Jun 2-Jun 24-Jun 30-May 25-Jun
Calico scale (soft) 714 Crawlers (only) 28-May 2-Jun 31-May
Striped pine scale (soft) 750 800 Crawlers (only) 30-May 2-Jun 4-Jun 7-Jun 2-Jun 6-Jun
Oak lecanium scale (soft) 789 Crawlers (only) 1-Jun 6-Jun 5-Jun
Cottony maple leaf scale (soft) 802 1265 Crawlers (only) 2-Jun 23-Jun 7-Jun 29-Jun 6-Jun 30-Jun
Cottony maple scale (soft) 802 1265 Crawlers (only) 2-Jun 23-Jun 7-Jun 29-Jun 6-Jun 30-Jun
Golden oak scale (Pit) 802 1266 Crawlers (only) 2-Jun 23-Jun 7-Jun 29-Jun 6-Jun 30-Jun
Japanese maple scale 829 Crawlers (Gen 1) 3-Jun 9-Jun 7-Jun
European elm scale (soft) 831 1388 Crawlers (only) 4-Jun 27-Jun 9-Jun 4-Jul 8-Jun 6-Jul
European fruit lecanium scale (soft) 932 1645 Crawlers (only) 9-Jun 7-Jul 14-Jun 14-Jul 14-Jun 17-Jul

*Conifer / Christmas Tree scales

Please visit the Rutgers Ornamental IPM Website – Pest and Disease Index (click here) for more detailed information on specific scale species management and pesticide considerations.

Box tree moth – stay vigilant looking for this pest

Box Tree Moth (Cydalima perspectalis) is alive and well in MD, DE, VA, WV, NY, OH, MI, MA. Please report this pest to twaller@njaes.rutgers.edu

If this pest does make its way into New Jersey, and quarantines are established, nurseries will be required to comply with a federal compliance agreement if shipping out of potential quarantine areas. Please review this document if boxwoods are an important crop for you. Compliance Agreement for Production Nurseries in BTM Regulated Nurseries (click here)

Box tree moth caterpillars. Photo credit: USDA.