Vermont Forest Pest First Detector Program Forests, Parks & Recreation Agriculture, Food & Markets Presented by: Caitlin Cusack UVM Extension

Non-native - Asian Invasive Exclusive to hemlock trees Kills hemlocks Native trees not resistant No effective native natural enemies

Hemlock Springs Overlook Shenandoah National Park

Most adelgids are killed when winter temperatures exceed – 22 degrees F. They are more sensitive to cold temperatures in March than in Jan.- Feb. They are likely to evolve to withstand colder winter temperatures over time. Global warming should have a positive effect on adelgid survival and movement north.

Vermont Forest Pest First Detector Program Damage

Slow twig growth Discoloration Die back,thinning crown Eventual death

How does HWA spread?

Natural spread by Wind, Birds, & Mammals

Photo: B. Burns Stump of infested tree

Eradication of outlying populations Suppression activities on leading edge Integrated management in infested areas Surveys Quarantine Preserving genetic resistance “X” Factor

Early detection is critical Most discoveries are made by informed citizens

Be on the look out – call if you find it Take your bird feeder down in early spring Don’t buy nursery stock from infested areas Keep your hemlocks as healthy as possible Don’t rush to salvage hemlock prematurely Get others involved – start a local monitoring program

Please return to the First Detector Resource webpage at and complete the Module 3A Quiz. For more information and ideas: Go to take-stand-hemlock or Contact Jim Esden