Scales

Scales are sucking insects with tube-like mouth-parts they insert into the leaves to extract the nutrient rich sap found within. Their feeding causes the foliage to yellow and shed prematurely.

Monitor plants for the following scale insects starting in mid-June. Wrap double-sided sticky tape around twigs to monitor crawler activity. Most scales can be managed at this time by applying a Summer oil spray to infested plants.

 

Scale

Hosts

Comments

Fletcher Scale

Arborvitae, juniper, cypress and yew

Look for yellow-brown hemispherical adults, honeydew-like substance and sooty mold on twigs and needles.

Cottony camellia Scale

Holly, camellia, yew, euonymus and maple

Look for white, cottony, wax ovi-sacs on underside of leaves.

Oystershell Scale

Fruit and most shade trees; boxwood

Look for oystershell-shaped, brown-to-gray scale covers on bark.