Landscape - Current Pests

The following are pests that are currently active in Delaware landscapes.

Tuliptree scale and magnolia scale crawlers are active. Horticultural oil and Distance provide good control.

Magnolia scale. Photo by Brian Kunkel, UD Extension

Tuliptree scales. Photo by Gerald J. Lenhard, Louisiana State Univ, Bugwood.org

European Hornets/German Wasps and Yellowjackets are very active. They are predatory natural enemies of other insects but may need control, especially where food or food crops are present.

Late season leafhooper and lace bug damage is showing up. On evergreen plants, (Azalea and Andromeda), a fall horticultural oil application may reduce lacebugs and their eggs that would potentially overwinter on leaves.

Information from the September 18, 2009 edition of the Ornamentals Hotline newsletter from University of Delaware Cooperative Extension.

Landscape - Scale Insects: Tuliptree Scale

This is the 22nd in a series on scale insects in the landscape. This post is on the Tuliptree Scale. Information is from the University of Maryland.

Tuliptree Scale (Toumeyella liriodendri), Family Coccidae

Plants Damaged: This native soft scale prefers tuliptree and magnolia.

Damage Symptoms: Dieback of twigs and yellowing of foliage. Black sooty mold often
grows on the honeydew that this scale excretes.

Life Cycle: They overwinter as black immatures and begin feeding around late April. The tuliptree scale females swell up in August and produce copious amounts of honeydew. The black crawlers emerge in September to October.

Monitoring: Tuliptree scale tends to be found on small branches, whereas the magnolia
scale is more commonly found on the main trunk.

Control: When crawlers are out, Distance mixed with 1% horticultural oil gives excellent control or use a systemic labeled for soft scale like Merit (imidacloprid) or Safari (dinotefuran).


Information from "Scales Commonly Encountered in Maryland Landscapes and Nurseries" by Stanton Gill, Extension Specialist in IPM for Nurseries and Greenhouses,and Suzanne Klick and Shannon Wadkins, Technicians, Central Maryland Research and Education Center University of Maryland Cooperative Extension.