The Greening of America

New York faces a similar squeeze. Bloomberg plans 220,000 trees along city streets, which essentially means "a tree in every single place where it is possible to plant a street tree," Deputy Mayor Dan Doctoroff told the Associated Press. Another 380,000 trees will be planted in parks and shoehorned onto traffic medians, and the remaining 400,000 will be the responsibility of community organizations, businesses, cooperatives, developers and any New Yorker with a patch of dirt and a shovel.

Treewise, "Washington is in pretty good shape," says Mark Buscaino, executive director of Casey Trees, a community group that helped plant 1,500 trees in the city last year. Canopy cover in Washington is a nice, leafy, green 35 percent, he says, and per capita the city spends more than New York or Los Angeles on its forest, which includes about 120,000 street trees.

To the community of activist-arborists, a tree is really so much more. Trees ease stress, fight cancer, lower crime, build civility, store water, bolster real estate prices, etc. They exhale oxygen, inhale carbon dioxide. Yet while the mayors stress the importance of trees in the fight against global warming, their ability to sequester heat-trapping greenhouse gases is not that super-duper.

Consider: There are 1.9 million trees in Washington, a mature urban forest that in a single year absorbs the amount of carbon dioxide emitted from the tailpipes of 9,700 cars, according to David Nowak, a research scientist with the Forest Service. So planting a million new trees is a drop in the bucket, especially in a city such as Los Angeles, where there are 5.2 million vehicles registered in the county. Actually, the greatest benefit of trees is shade, which reduces energy use in the summer.

But everybody likes trees, right? Apparently, no. According to the community tree planters toiling on the streets, businesses don't like trees (when foliage blocks signage). Bureaucrats don't like trees (because they're a hassle). And despite what they say now, politicians have not been tree huggers. The first item cut in any tight budget year is usually tree maintenance. "When you say, 'What's the cost of a tree?' it is more than buying a tree and putting it in the ground. It's also taking care of it," says Ray Tretheway, executive director of the Sacramento Tree Foundation, who explains it takes two or three years for a tree to establish a home.

Here's a great idea: free trees. Los Angeles has sponsored hundreds of "tree adoptions." But what happens when the saplings go home? "When we plant street trees, we make sure the soil is amended, we stake them, tie them, mulch and add nutrients. We have people committed to watering them," says Dore Burry, the environmental services manager with the Koreatown Youth and Community Center, which has planted 2,600 street trees for Million Trees LA. "When you give away free trees, we have very little assurance of high survivorship."

Especially, when cities give away small, vulnerable six-inch seedlings in bags or tubes -- the kind of tree offered today, on Arbor Day, around the country. Many arborists now urge cities not to distribute free seedlings for fear the green swag just ends up in the trash. Los Angeles recently stopped the practice.

Planting street trees often requires both a city permit and the permission of neighbors, who give many reasons for not wanting a tree at the curb. They don't like dogs, who do like trees. Tree activists have heard people complain about sap, birds, squirrels, spiders, leaves and shade. Oh, and they don't want their views blocked.

Burry explains that neighborhoods with the fewest trees are the toughest places to plant. "These are often the harshest environments, communities on the bad side of environmental justice issues -- lots of renters, working class, two-job individuals. For us it is much more costly." Burry says it takes intense community outreach -- many meetings, much door knocking, to get neighbors to agree to plant and care for new trees. Then: "Sometimes there has been no organic life on the street in 20 years. The soil is extremely dry, nutrient-poor, compacted. We have to pour gallons and gallons of water and just let it sit, and still sometimes you dig and it's like concrete. This loud clang." Other challenges? "They don't have water hoses," Burry says.

Trees in Los Angeles are tagged with gang graffiti. Vandalism is not uncommon. So is aggressive pruning by municipal trimmers, which can leaves trees with severe, lethal haircuts ("trim more than 30 percent of a pine and you've killed it," Lipkis says). Certain species of trees planted beneath street lamps can fry themselves out by attempting to photosynthesize 24 hours a day. The average life span of a street tree is seven years, because mortality is so high in the first few years.

Since the Million Trees LA program began, the city and its partners have added 141,357 trees to the urban biosphere. Or so they hope. Half of those trees were given away as seedlings or adoptions. It's anybody's guess whether they are still alive. Bottom line? Los Angeles can account for at least 70,000 new trees in parks, on streets, around schools and developments, which is many times more trees than they were planting before.

"It's ambitious, it's a very, very ambitious goal," says Larry Smith, executive director of North East Trees, one of the community groups working on the Million Trees LA project. "The reality of what it takes is settling in. We want a million trees but what we really want is healthy, mature, urban trees. We want trees we can take care of, not just numbers."

Says Lipkis: "The danger is that it becomes all about reaching a million," and that it becomes a public relations ploy, and not a forest. "You could fly a helicopter over L.A. and dump out a million seeds, but that's not the point, is it?"

Staff writer Ashley Surdin contributed to this report.