Cape Elizabeth · Cumberland County

Hemlock Woolly Adelgid Treatment in Cape Elizabeth, ME

Keep the hemlocks on your Cape Elizabeth property healthy. Hemlock woolly adelgid is established in Cape Elizabeth, and Tree Medics treats it across Cumberland County and Southern Maine.

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Inspecting a hemlock branch for woolly adelgid
CountyCumberland County
HWA in Cape ElizabethEstablished
Check twigsTwice a year
One treatment can last4+ years

Hemlock woolly adelgid is a tiny, aphid-like insect from Asia that feeds on the sap of eastern hemlocks. Over several years, a heavy infestation can starve a hemlock of the stored energy it needs to grow, and the tree slowly declines. Cumberland County is entirely within Maine’s hemlock woolly adelgid quarantine.[1]

Hemlock woolly adelgid in Cape Elizabeth

As of December 2024, the Maine Forest Service lists hemlock woolly adelgid as established in Cape Elizabeth, and says it is widespread along the southern coast.[2]

Treatment options for hemlocks

Long-lastingImidaclopridFor hemlocks under three feet in diameter, one soil application can keep adelgid below damaging levels for more than four years.[3] It moves slowly, taking a year or more to reach the top of a large tree.[4]
Fast-actingDinotefuranMoves through the tree faster, which makes it useful for heavily infested hemlocks, but protects for only one to two years.[4]
Small treesOil and soapHorticultural oil and insecticidal soap can work on small trees, but need thorough coverage once or twice a year.[3]

How we treat hemlocks in Cape Elizabeth

Step 1InspectWe check the underside of branches for adelgid and judge how much healthy foliage the tree still has.
Step 2Choose the right treatmentHeavily infested trees may need fast-acting treatment first, while healthier trees can get long-lasting protection.
Step 3MonitorWe keep an eye on treated hemlocks so they can be retreated when needed.
Hemlocks respond best when treated early.

Systemic treatments rely on the tree to move them up into its branches. A hemlock with plenty of healthy foliage takes up treatment far better than one that is already in steep decline. Untreated infested hemlocks are likely to die within four to ten years.[4]

Why hemlocks matter

Eastern hemlocks are long-lived, shade-tolerant evergreens that provide year-round screening, shade streams and hold soil on slopes. Losing a mature hemlock changes a property, and replacing one takes decades.

Want the full picture? Read our complete guide to hemlock woolly adelgid treatment in Southern Maine.

Hemlocks and woods in Cape Elizabeth

Local landscapeCape Elizabeth is a Cumberland County town with a 2020 Census population of 9,535 and a land area of about 14.9 square miles.[5]
Hemlock woolly adelgidCape Elizabeth reports that biological control agents for hemlock woolly adelgid were released at Winnicks Woods in 2023, as eastern hemlocks in neighborhoods and town woodlands face a serious threat.[6]
Beech leaf diseaseAs of fall 2024, beech leaf disease had not been confirmed in Cape Elizabeth, and the town asked residents to report possible sightings.[7]

Hemlock Woolly Adelgid help near Cape Elizabeth

Tree Medics is based in Biddeford and works throughout Southern Maine. We also offer hemlock woolly adelgid services in nearby towns:

South Portland, MEScarborough, MEPortland, ME

See all tree care in Cape Elizabeth.

Sources

  1. Maine DACF: Hemlock woolly adelgid quarantine counties and towns
  2. Maine Forest Service: Hemlock woolly adelgid overview and distribution
  3. Maine Forest Service: Hemlock woolly adelgid fact sheet
  4. Michigan Invasive Species Program: Plan to treat trees for hemlock woolly adelgid (2026)
  5. U.S. Census Bureau: QuickFacts, Cape Elizabeth town, Cumberland County, Maine (2020 Census)
  6. Town of Cape Elizabeth: Tree Alerts for Fall/Winter 2024 (2024)
  7. Town of Cape Elizabeth: Tree Alerts for Fall/Winter 2024 (2024)
FAQ

Hemlock Woolly Adelgid in Cape Elizabeth: common questions

Is hemlock woolly adelgid in Cape Elizabeth?

Yes. As of December 2024, the Maine Forest Service lists hemlock woolly adelgid as established in Cape Elizabeth.

How long does treatment take to work?

Imidacloprid moves slowly and can take a year or more to reach the top of a large tree. Dinotefuran moves faster and is often used on heavily infested trees.

Can a hemlock with adelgid be saved?

Often, yes, especially when treatment starts while the tree still has plenty of healthy foliage. Untreated infested hemlocks are likely to die within four to ten years.

What does hemlock woolly adelgid look like?

Look for small white, cottony masses on the underside of young hemlock twigs at the base of the needles. Check twice a year, at the start and end of Daylight Saving Time.

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Worried about a tree?

Many tree health problems can be managed when they are caught early. Reach out today for a professional evaluation.

(207) 303-7291 SaveMyTrees@TreeMedics.com

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