New Troubles for Virginia Trees

May 31, 2019

One of the easiest things people can do to confront climate change is to plant more trees.  They suck carbon dioxide from the atmosphere, provide shade that reduces the need for air conditioning and prevent erosion, which helps to keep water clean.  Unfortunately, Virginia makes it easier for people to cut down trees than to plant them.

Invasive vines can grow big enough to bring down Virginia Trees.
Credit RadioIQ

Virginia is for lovers – and for trees.  Sixty-two percent of our land is forest.  That’s actually up from 1940, when the state had more farms, but lately we’ve been losing trees to development.

“We know that Virginia is very friendly towards business, and any time you’re embarking on a business enterprise that means that a piece of land is going to be developed,” says Eric Wiseman, an expert on urban forest management and a professor at Virginia Tech.  He e notes towns, cities and counties in this state have limited powers when it comes to trees.  Localities can, for example, ban cutting of historic specimens or require developers to plant enough new trees to shade 20% of the property in 20 years – but those little patches of forest are vulnerable:

“The lands and parks that you might find that are mixed into a city that haven’t undergone development or are set aside for perpetuity, that’s where you commonly see the negative impact of exotic, invasive plants,” Wiseman says.

Aggressive vines can sometimes kill trees.
Credit RadioIQ

Like kudzu, Japanese honeysuckle, oriental bittersweet or English ivy – plants that can climb into tree branches and eventually pull them down. Trees can also be attacked by bugs and disease – increasingly common because of global trade.

“Our native trees have very limited resistance to them, and therefore those insects and diseases move + through the tree populations and cause destruction,” he explains.

In this – the age of climate change – Wiseman adds that forests are increasingly vulnerable to bad weather.  The Shenandoah National Park, for example, is still recovering from a storm that hit in November.

“Whether we’re talking ice storms or flooding or hurricanes or even in certain parts of Virginia occasionally, tornadoes touching down, they’ll uproot trees, they break trees and they also end up in a little bit of an understandable backlash against trees – that is people get a little fearful in the wake of a storm, and they’ll often times go out and after the storm has passed through and take down even more trees.”

And, finally, climate change itself could be detrimental to Virginia forests.

“There are projections that show Virginia getting warmer, but also in certain parts of the state getting wetter, or in certain parts of the state getting dryer, and because trees are long-lived organisms and because they are stationary, they can’t get up and migrate, we need to be thinking about what do we plant now that’s going to be adaptable and resilient to whatever climate might bring for us in 40, 50, 60 years.”

On a more encouraging note, the excess CO2 in our atmosphere can be a good thing for trees.

“CO2 enrichment of the atmosphere is actually to trees’ benefit, right?  That’s how they make their food, and it increases what’s known as their water use efficiency – that is they can better tolerate drought, so the question then becomes where’s the tipping point between that CO2 enrichment and increasing temperatures which can be a source of stress for trees.”

And given Virginia’s commitment to protecting the Chesapeake Bay, farms and cities are using trees to reduce erosion – their roots holding the soil so it doesn’t slip into rivers and streams. The state may limit the protection communities can extend to trees at the expense of development and private property rights, but homeowners’ associations are playing a greater role – and if residents are willing, Wiseman says, those organizations they can make tree-friendly rules.