Wednesday, August 4, 2010

Drought Still Affecting City Trees

Despite the heavy rainfall we've been experiencing in Edmonton recently, the city's trees are still suffering from the impact of the droughts of the past few years. According to Michael Silzer, an ecological planner with the city, 30 percent of the natural areas within the city are experiencing dieback. "Dieback" is the condition in which trees have many dead or dying branches. This spreads over the tree until it doesn't have the strength to combat the problem and the tree itself dies. Pruning can help the tree survive longer and allow it time to recover.

Some of the ways to keep city trees health are:
  • create wells around tree trunks to catch moisture
  • fertilize and water trees regularly
  • don't place rocks or cement near or around the base of trees (use mulch instead)
  • keep road salt away from trees

When trees reach the end of their life cycle and either die or have to be removed, consider planting a new tree. When planting, remember that the tree will not always be small--give it sufficient space in which to grow. Coun. Karen Leibovici has recently been urging city council to encourage the public and businesses to plant more trees since so many Edmonton trees have died because of drought, disease, and old age. This would not only contribute to a richer and more beautiful urban forest, but it would save the city a great deal of money. According to the Edmonton Journal, it cost the city $743 for parks workers to supply, plant, and maintain each new city tree it planted last year. The city has recently embarked on a three year program to replace those trees killed by the long drought. The plan calls for roughly 3,000 trees to be planted.

New Book on the Global Forest

Author Diana Beresford-Kroeger, a botanist and arborist, has recently published a book entitled The Global Forest, in which she describes trees as the most special species on the planet. She points out that 50 percent of the oxygen of the air comes from trees. The other 50 percent comes from phytoplankton and algae, the "invisible forests of the ocean" (also under attack, given recent news reports). Beresford-Kroeger thinks that humans have underestimated trees and their importance and that "if the trees die, we die." Her book is a call for a new, deeper understanding of the importance of trees to global survival.