Winter Survival Strategies

by Sheila Newman, Earth Stewards Committee

Photo 121071914 / Adelgid © Jason Ondreicka | Dreamstime.com

The original inspiration for an Earth Steward’s blog came from above. The canopy of the trees around us--(apologies to Rachel Carson, author of “The Sea Around Us”)--invited an essay on what their winter shapes tell us; who they are and when to hear them announce “spring has truly begun!”

The topic seemed timely in early February when most of us in the Northeast are usually sick and tired of winter and signs of spring are so welcome. Instead of bemoaning winter, I wanted to share a lens into our winter environment, an environment that most people do not find interesting or informative.

You may wonder, “What makes a tree interesting if there are neither leaves nor buds on naked boughs?” The answer is “lots”, unless climate change intrudes, and the “normal” February view no longer exists in lowland places. Already our woodlands and gardens show the effects of the warming of the globe, but an essay about trees talking will have to wait until next January.

All is not lost. Instead of looking through the sky above, let’s turn our gaze downward and inward to realms that reveal the winter survival strategies of two pests that affect familiar trees. The change of lens from trees to pests shows the importance of organisms we are less likely to notice. While invertebrates may be small, we ignore them at our peril.

Hemlock woolly adelgid (HWA): Hemlocks and Ash are trees common to residential landscapes and characteristic species of Northeastern forests. Due to the Emerald Ash Borer (EAB), the Ash has practically disappeared from the Northeast; a great loss of a majestic tree. The Hemlock Woolly Adelgid (HWA) greatly stresses Hemlocks. In a worst case scenario, the aphid-like insects’ infestations can kill a tree. HWA remain active throughout the winter. In their nymph stage, they attach to the base of the twigs through their sucking mouthparts. During these winter months, they continue to feed on the tree, exuding a white, waxy wool to help protect them from the elements. Imagine having a body engine that makes a winter coat!

Emerald ash borer (EAB): Emerald ash borer spends the winter in the sapwood of ash trees. The tree’s outer bark acts as insulation, keeping temperatures inside the tree warmer than the outside air. EAB larvae use a strategy called “supercooling” to survive the winter. They can cool their body fluids below its normal freezing point without actually freezing. They do this by producing “antifreeze” proteins that prevent the water in their bodies from freezing. Personal antifreeze would serve us well, too. Consider all the ways it would add to our enjoyment of winter out of doors.

The text in blue is a link to DEC information that greatly expands this invitation to know more about them.

And if you have Hemlock, now is a good time to look for the waxy wool of Hemlock Woolly Adelgid. They can be controlled with an environmentally safe spray that arborists dispense.