Web extra! View pdf’s of the forestry commission’s commentary and recommendation.
At no time since Dutch elm disease devastated the American elms lining village parkways in the 1950s and 1960s has the health of our urban forest been so threatened. The Forestry Commission is recommending that the board restore the entire 2009 tree planting budget of $100,000 for a fall planting program.
The village removes on average 150 to 250 elm trees a year. The number of elms dying this year has increased substantially, necessitating the removal of many of the largest tree canopies in the village.
Emerald ash borer has been identified in some of our largest ash trees. It’s likely that most of the 2,600 parkway ash trees will require removal over the next 10 to 15 years.
The village can also expect high losses of mature maple trees due to the end of their natural lifespan. The combined totals of threatened American elm, ash and mature maples represents 35 percent of the village’s total parkway tree inventory.
Prior to emerald ash borer, about 400 trees were removed annually; but those numbers could potentially reach 600 to 800 trees or more.
The continued loss of large canopied trees in the village, without an aggressive tree planting program, may have long-term negative impacts on our local environment, economy and aesthetics.
Documented studies have shown the enormous value trees provide to a community, and that the larger the canopy, the greater the benefits. Studies show that a well-maintained urban forest improves air and water quality, moderates summer air temperatures, increases carbon storage, provides energy savings for heating and air conditioning, provides shade, extends the life of asphalt paving, increases home values, increases sales in retail districts, improves the quality of life, reduces crime, and promotes a sense of wellness.
Trees are a fundamental component of the movement to “green” our infrastructure and the village has voiced a commitment to sustainability. There is no single infrastructure investment that provides such long-term benefits for such a modest initial investment. And the benefits increase with time.
If we skip even a year of tree planting, we’ll lose a year’s growth, further declining the number of parkway trees. Catching up will be difficult.
We recommend the current 35-foot spacing be retained. That distance is typical of similar Illinois communities, seems appropriate for our lot sizes and provides a better continuous shade canopy for our tree-lined streets. The village forester already has discretion to increase that spacing based on conditions such as overhanging private-property trees. We recommend the minimum tree diameter be reduced from 2.5 inches to 1.5 in some cases. That will allow a wider choice of species, reduce establishment time and decrease watering and follow-up maintenance.
Oak Park cannot afford to eliminate the 2009 tree planting. Oak Park should join other communities that are adopting ambitious tree-planting programs because of their proven benefit.
Kathryn Jonas, an arborist, is a member of the Oak Park Forestry Commission, a seven-member advisory panel appointed by the village board. Also on this volunteer panel are other arborists, environmentalists and interested citizens. The commission’s full recommendations are available from the village Public Works department and at www.wednesdayjournalonline.com.