Davey uses cookies to make your experience a great one by providing us analytics so we can offer you the most relevant content. By continuing to use this site, you accept our use of cookies. View our Privacy Policy for more information.

Elongate Hemlock Scale

Elongate Hemlock Scale is a species of scale insects that is armored with a hard, waxy covering. The insect damages hemlock needles by inserting needle-like mouth parts into leaf tissue and removing cell fluids.

Symptoms the host tree experiences include:

  • Yellow spots developed on the upper surface of hemlock needles
  • small, oblong flattened insects on the lower needles 
  • yellowing needles and defoliate in severe infestations 
  • trees appearing off-color with a sparse canopy 

The elongate hemlock scale is a pest of various hemlock species, including the native eastern hemlock and California hemlock. This scale is also occasionally found on yew, spruce and fir, although damage is not usually severe.

Management and Treatment

Natural insect predators of the scale exist, but they cannot be solely relied on for effective control on valuable ornamental hemlocks. A winter oil treatment plus one or two applications during the growing season can provide effective control. Adequate scale control may also take a few season if it is a large population. 

Soil injection of Davey's slow-release fertilizer Arbor Green PRO® will increase tree tolerance to scale damage and also speed recovery from previous scale feeding damage. 

Find your local certified arborist to request a consultation if you are worried plants are being affected by the Elongate Hemlock Scale. 

Request a consultation

  • Homeowners looking for services for their residential property, contact your local Davey office.
  • How would you like to be contacted?
*Please fill out all required fields.