Saturday, September 18, 2010

Trees are the Answer, Not the Problem

It is frightening to see a large tree fall.

I was walking once at Brookside Gardens on a beautiful sunny day in the middle of the autumn two years ago when I saw one go down in the forest along the horizon. It made an awful sound, and the weight of it made the ground shake around our feet for a moment. You feel a pit in your stomach when that happens. You feel small and helpless.

A lot of people recently experienced this first hand, when massive trees fell along our streets and in the parks. Two families in my own neighborhood even lived through the horrendous experience of having massive oaks fall directly on their homes. Everyone living in both homes came out safe and sound, thank God. The clean up efforts have been slow and hard and my heart goes out to them.

Yes, it is scary to watch trees fall, and also frustrating to experience power losses. I would not deny that.

But as politicians and Pepco argue over questions of management and the public grows increasingly frustrated, I’d like to reframe with a different perspective. We’ve lost a lot of trees this year, and now more than ever we need to be planting replacements.

When I hear people begin to talk as if the trees themselves are problem, I get worried. Trees are not the problem. In fact, I think that trees are the answer. Rather than see them as the cause of our human woes, we need to understand why they are here, acknowledge their importance in our landscape, and manage to somehow live our lives safely in their presence. Because without large trees we would really be in trouble.

Trees, many people know, help reduce air pollution and cool the air. The cooling occurs not only because trees provide enormous amounts of shade, but also because a mature tree actually moves water into the atmosphere.

What a lot people sometimes overlook, however, is that a forested landscape can also reduce the impact of water pollution and slow or reduce flooding in urban areas. That’s because when stormwater is able to move across tree roots, it is readily absorbed by the tree. The roots and the other living things in the soil and leaf litter act as excellent filters. They do this naturally and are quite effective at it.

Although water moves considerably slower through a forested landscape then through a cement-covered one, we’ve done a lot of work lately to fill our watershed with a huge amount of hard surface in the form of parking lots, roads and rooftops. This, in turn, has caused an increase in pollution and flooding, even when the storms aren’t unusual in intensity.

Where once there were fields and forests, there increasingly tends to be concrete and asphalt. Where once, the water moved as if it was moving through a sponge, it now moves as if poured from a smooth pitcher.

All of this is not good for the creeks, which get scoured out by the fast moving water and begin to erode. In the metaphor above, the pitcher is not clean but covered in oily and nutrient-rich pollutants which are washed into the stormdrains and then into our creeks. The abundance of things like fertilizers and pesticides from our lawns and streets can lead to anaerobic and toxic conditions. Our waterways become less inhabitable for fish, turtles, and other wildlife. The waterways, including the Chesapeake, become unhealthy.

“Dirty water kills,” Arlene Bruhn told me recently. She’s written the county council numerous times to advocate for more trees and better tree protection laws. Trees are essential to protecting our water supply, because we drink the Potomac’s water, she added.

Bruhn also reminded me that we’d had the hottest DC summer on record, meaning that we need as many shade trees as possible to help cool the city.

It makes sense, then, to protect the buffer zones of trees around creeks and plant more trees planted throughout our watershed. Does that mean we should plant trees any old place? No. What it means is that we need to be smart about where we plant and what we plant. It also means that we need to take care of what is already there.

“When you go to a garden center and see a tree in a little pot it is like looking at a little preschooler,” Mike Galvin, Deputy Director of Casey Trees told me recently. His organization works hard to get more trees planted in the city. “You need to say, what is this tree going to look like when it is mature, just like you try to think ahead to your kid’s future and how they are going to grow and get big.”

I liked Mike’s analogy. But sadly it reminded me of a story that an older friend here in Silver Spring told me last year. She recalled a time in the early 1950s, right after the houses were built in her neighborhood, when all of the people along one street bought some trees. We walked out one Saturday and planted them together, she recalled with warmth.

I appreciated the civic pride her story demonstrated, but I cringed when she pointed to the trees they had planted. Oaks, maples and gums were all there, directly under existing power lines in what is sometimes called the Right of Ways or ROW along the curblines.

Those trees then grew to be beautiful, treasured, big and dramatic. They also grew to be big problems for power line companies, well-managed or otherwise. And those trees often struggled to grow strong roots where the sidewalks existed. Those happy neighbors had definitely not thought ahead to the day when their baby trees would be mature.

In the decades since, we’ve struggled to do a bit better, with very little success. Municipal arborists now oversee ROW planting. Some developers have undergrounded lines as technology and innovation made this safer. Some who were really progressive even built developments which allowed for central green spaces full of trees. But many did not, opting instead to squeeze as many houses as possible into each space they developed. As a result we continue to lose our existing canopy at an ever increasing rate. New trees do not see to be a real priority for the county or the state.

We need to do a better job in the future. Homeowners can start by planting wisely. If you select a tree to plant, research and understand the tree before you begin. Don’t be afraid to pick a big one, but look up before you plant and see if there are powerlines there first.

If you don’t have space for the big, mature shade trees, pick one that will naturally stay small. Don’t pick a big species and try to train it to stay small. That only leads to pain for the tree and trouble for you or the next homeowner.

You can also work to maintain existing trees, both big and small. Too often, suburban folks tend to see trees as static, architectural features. Instead we need to understand that they are living, dynamic things that change and grow and sometimes begin to decline. They need regular attention in the form of professional pruning by a certified arborist.

The storms of summer have subsided for now, but I have no doubt we will face new ones again soon. Hopefully, we’ll at least get a healthy amount of rain. All those new seedlings I hope to see out there will need it.

This piece originally appeared in the Sept edition of the Voice newspapers of Takoma Park, Silver Spring and Kensington.

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