Trees and global warming in your garden

by Susan
We've all read what experts in global warming have to say about the environmental benefits of trees.  And from the gardening world we see articles offering "Tips for Choosing Small Trees for your Yard".  But when carbon counts are tallied by an experienced gardener, it suddenly gets more interesting to people like us, so I recommend to you this piece by Adrian Higgins in the Washington Post.  Here are my favorite bits.

CARBON COUNTING
People who study this stuff say that an 18-inch-diameter white oak will remove 622 pounds of carbon dioxide from the air every year.  Sounds good, right?  But the average two-person household in the U.S. releases 41,500 pounds of carbon dioxide into the air annually.  So if you don't have room for the hundreds of mature trees required to remove that much, Higgins suggests donating to American Forests - they'll plant them somewhere else.

Then you can increase the carbon benefits of a tree 15-fold by using it to shade the house in summer. Remember the solar panel v. tree battle that recently got so much news?  More to come.

And of course the benefits of trees go beyond carbon sequestration to filtering pollution, preventing erosion, providing wildlife habitat and making us all happier.

Go to Casey Trees' website to use their "neat" calculator of carbon sequestration. You can determine exactly how much carbon is being sequestered by the trees on your property, as Higgins did for his.

AND WHAT GARDENERS NEED TO KNOW ABOUT TREES

A lot of people are surprised when small trees become large trees and the altered light conditions reduce the number of flowering plants to choose from, or the chances of raising a tomato vine or growing grass.  It changes the character of a garden, which is fine, but you should know that. 

If you plant a tree, you should do your best to keep it alive...Some experts believe it takes five years to plant a tree.

Beyond all the obvious reasons to keep our trees alive, Higgins reminds us that dead trees stop capturing carbon.  Then when they're chopped up into mulch and start decomposing, most of the carbon stored in those chips is released right back into the atmosphere.  There's that damn cycle of life going on.

Comments

[Benjamin]

Truly a fascinating post, Susan, and great links. I've too many trees of various size on my 1/4 acre (like 12, I think), so adament am I about wildlife, cooling the home in summer, and blocking unsightly neighbors--don't forget that less "environmental" benefit of trees.

[eliz]

I was a bit surprised by Higgins reporting this as though it was big news to him (opener of article). Though that may have for effect.

[Ginny Stibolt]

Susan, In researching my sustainable gardening for Florida book I found these suggested irrigation requirements after planting trees: (This is over and above any general landscape irrigation or gentle rains. If you experience several inches of rain over a day or two then irrigation of trees can be lessened for a few days.)
Each time you irrigate, it's best to water with three gallons per inch trunk caliper (the diameter of the trunk at six inches above the root ball of saplings). For example, use six gallons for a two-inch caliper tree. Apply slowly, so all water soaks into the root ball. Drip bags or drip donuts can help.
If a tree is two to four caliper inches, the best practice is to water daily for one month; every other day for the next three months; and after that water weekly until established. If a tree is more than four caliper inches or if it's a palm, the best practice is to water daily for six weeks; every other day for the next five months; weekly after that until established.
After the initial period, continue to supplement irrigation for your tree during drought conditions for at least a year. Two is better.
Plant more trees, but only those you can care for after they are planted. The old advice of planting the largest tree you can afford should be changed to plant the largest tree that you'll have the time and will to care for.
Hey, plant a tree for Mothers' Day. Mother Nature will thank you. Ginny

[Jon Beard]

"We know that we who reside in the United States emit about 6.2 billion tons of carbon dioxide into the atmosphere each year," said Taro Takahashi, Doherty Senior Research Scientist, associate director of Lamont-Doherty, Columbia's earth sciences campus in Palisades, N.Y., and an author of the report. "As an air mass travels from west to east, it should receive carbon dioxide and the East Coast concentration of CO2 should be higher than on the West Coast.

"But observations tell us otherwise. The mean atmospheric CO2 concentration on the East Coast has been observed to be lower than that over the Pacific coast. This means that more CO2 is taken up by land ecosystems over the United States than is released by industrial activities."

http://www.sciencedaily.com/releases/1998/10/981020074617.htm

Planting trees is a very good idea. Thinking that fossil fuel burning by man is causing global warming when this accounts for only 3% of CO2 production versus 97& produced naturally is allowing yourself to be deluded. 383 PPM or .000383 parts of the atmosphere is carbon dioxide. 3% of this is man made (.03) Man's contribution therefore is .000383 times .03 or .00001 part of the atmosphere. This 1/100,000th part of the atmosphere cannot warm the earth.

Of course without trees and plants we would surely die and they certainly are essential to cleaning real pollution from the air. I just wish there was something that could as efficiently cleanse the political nonsense of human caused global warming.