January 20, 2005
Protection Does Grow on Trees
Another year, another tree story -- isn't it enough already?
Well, no. Tu b'Shevat is an annual celebration for a reason.
Thousands of years ago, our rabbis knew that we would need to be reminded on a regular basis about how important trees are to our lives. We must always remember to protect, plant and care for more of them.
The rabbis were prophetic. Despite and perhaps because of the nature of our annual celebrations, we tend to see trees as only quaint, lovely and generous. They beautify our streets and provide shade when the sun shines. But with this somewhat simplified perception, we sometimes miss the absolutely essential role that trees play in our lives -- even our urban lives -- today. Trees protect us.
Consider the tsunami that struck the Indian Ocean just after Christmas 2004. At the time of this writing, more than 150,000 people in 12 countries were reported killed by the colossal wave that followed a massive earthquake. Villages and towns thousands of miles away from the quake's epicenter were devastated by the power of the water.
There was, however, a small miracle in all of this. According to numerous environmental scientists, in a select few locations where natural mangrove forests were still intact, some villages were protected. Mangrove forests, which grow along the shoreline and coastal waters of tropical and semitropical land, are especially dense.
These forests protected the land and the people by absorbing the energy and force of the wave as it hit. As a result, the areas behind these forests suffered far less damage and far fewer people died.
Unfortunately, in most of the populated regions around the Indian Ocean, the mangroves have been cut down to make way for development and shrimp farms. These deforested areas suffered immense human and physical losses.
What a lesson! Researchers are now investigating whether an intensive mangrove forest restoration effort is needed to better protect the millions of people who live in tropical lowlands adjacent to coastal waters.
Trees can also protect us from floods, water pollution and drought. Consider the heavy rains and flooding that drenched Los Angeles in early January of this year.
Two-thirds of Los Angeles' soil is sealed, covered with roads, parking lots and buildings. When rain can't soak into the soil, it rushes off, creating dangerous flooding and carrying toxins that pollute our creeks, rivers and beaches. This pollution can make us sick and hurts the economy as beaches are closed and tourists seek other vacation spots.
To add insult to injury, when rainwater runs off into the ocean, it isn't available to recharge our aquifers or groundwater basins. This makes us more vulnerable to droughts. Losing the rainwater also forces us to pay for and import water from great distances, damaging the environment in those places as well.
But let's go back to quaint. In November 2004, a historic bill was signed naming the oak as America's official national tree. Designating this beautiful tree wasn't simply a sentimental gesture. Oak trees are more than aesthetic -- they are powerful protectors.
How powerful? We asked the U.S. Forest Service research lab in Davis to calculate a large oak tree's flood protection and watershed capacity. The results may surprise you.
Fully mature native oaks, with branch and leaf canopies 100 feet in diameter, have root systems equivalent to an underground area the size of a huge water tank. This area includes fallen leaves, mulch, humus and very porous soil. All that material is habitat for critters that dig and drill holes and tunnels into the soil: microbes, worms, bugs, lizards, snakes and rodents.
All together, this "water tank" of conditioned soil can be five feet deep or more. That tank -- perhaps it is better described as a sponge -- can capture 57,000 gallons of water in a 12-inch rainfall or flash-flood event.
But it doesn't stop there. All that mulch and all those microbes actually filter and clean pollutants from the water. Then the bulk of that cleaned water is sent deep underground to recharge the aquifer or water table.
Remove one large oak, and in storms like Southern California recently experienced, 57,000 gallons of floodwater are lost downstream, potentially flooding and damaging homes, neighborhoods and streets. Because this water is washed away in storm drains, the aquifer doesn't recharge and our local water supply dwindles even more.
We can and must learn from trees -- that's part of the Tu B'Shevat message. Trees can teach us and help us participate in tikkun olam (healing the world).
This has been TreePeople's evolving purpose for more than 30 years now. We must protect our heritage of old trees and local woodlands. We need to remove some of the asphalt and concrete and plant more trees, so the mulch can grab and slow the rainwater runoff, so the roots can hold the soil.
In our most urban areas there is often no longer enough room for trees to capture all of the rainwater. So we need to employ technologies that mimic the "sponge and filter" function of trees.
The TreePeople program, TREES (Trans-agency Resources for Environmental and Economic Sustainability), serves exactly that function. We are installing a citywide system of cisterns and infiltrators to help capture water runoff and recharge the aquifer -- just like a mature oak tree.
TreePeople -- in partnership with city and county public works agencies and the L.A. Department of Water and Power -- has established demonstration projects in the San Fernando Valley (Pacoima and Sun Valley), South Los Angeles, the Westchester/Los Angeles International Airport area and now at the TreePeople Center in Coldwater Canyon Park.
TreePeople is striving to create and nurture an urban forest, an integrated system of trees and technologies that make our city safer, healthier and more sustainable.
We teach the lessons of the trees to our children and neighborhoods (we have taught nearly 2 million students over the past 33 years, including many children from Jewish day schools).
A new citywide plan is emerging. Some of the best news from this past year is that the voters of Los Angeles understand. By voting for Measure O, many of these tree-inspired technologies and solutions will be funded and implemented.
Trees do many good things. Now is an excellent time to remember, thank and value them because beyond all else, trees protect us.
TreePeople, in partnership with COEJL (the Coalition on the Environment and Jewish Life), will host two Tu B'Shevat plantings on Jan. 23 and Feb. 6.
For more information contact TreePeople's forestry department, (818) 623-4840 or go to www.treepeople.org.