Climate Change May Threaten Survival of Some OP-RF Trees within 50 Years

Submitted by Lacey S. Brown, Urban Forester, Openlands What if the weather in Oak Park became so hot and humid that you could not survive outside?  This could be an imminent reality for 18,000 residents of Oak Park: the public trees of our urban forest.  Trees that are given proper care can live one hundred years or more.  But trees that are suited to Oak Park’s climate in 2011 may not be able to survive in the Oak Park of even 50 years from now.

When the USDA issued its hardiness zone map in 2006, updated from its previous 1990 map, many states had shifted one hardiness zone warmer in just 15 years. Hardiness zones refer to the geographic area in which a given species of plant can survive the area’s lowest temperatures.   As illustrated in the May New York Times article A City Prepares for a Warm Long-Term Forecast by Leslie Kaufman, the City of Chicago is already preparing for a climate similar to that of Baton Rouge, Louisiana.  The City has removed six tree species from its planting list, including the white oak, and has added several species more common to Southern planting zones.

While the city of Chicago is to be commended for their proactive planning, some wonder if changing the tree species list is the right thing to do.  Kathryn Jonas, a certified arborist, member of the Oak Park Forestry Commission and Openlands Treekeeper comments, “I do think [the article] created a stir without a lot of research.  There are many tree species that are suffering from all kinds of problems now and climate change is likely one of them.  But I do not think [species such as] the white oaks warrant being singled out at this point.”

While which species deserve to stay or go from municipal planting lists may be in debate, researchers in the field recognize that the makeup of regional forests is indeed shifting over time and are putting forth models that can be of use in planting plans.  The USDA Forest Service has created a Climate Change Tree Atlas based on the work of Dr. Louis Iverson and Anantha Prasad which predicts how species ranges will change according to three different climate change modeling scenarios.  Some overall nation-wide conclusions that they have drawn from this modeling is that there is high probability for substantial loss of spruce-fir, maple-beech-birch, and aspen-birch habitat, while habitat for the oak-hickory and oak-pine types would increase substantially.

While not the silver bullet to making planting plan decisions, municipalities can look to tree species with a wide hardiness range, that tolerate both current conditions with below freezing temperatures in the winter and possible future conditions of considerably hotter and more humid weather, when creating current planting plans.  TreeLink provides a comprehensive list of tree species in each hardiness zone across the United States.  Favorites like the Lace Bark Elm, Hackberry, Hophornbeam and Redbud are rated for hardiness zones from Northern Illinois to Southern Louisiana.

Related Posts & Resources:

Oaks for Oak Park!  Adopt a Tree as Part of the Historic Oak Propagation Project

Fall TreeKeepers Classes Begin September 10th

Village of Oak Park Forestry Division

Fall 2011 TreeKeepers Classes begin September 10th

Forest trees can live for over 100 years, but urban trees, forced to contend with pollution and limited space for growth, usually survive for only about fifteen years unless they receive special attention—approximately 1,000 trees die in Chicago every year due to neglect. That's why, since 1991, TreeKeepers have worked throughout the city to keep its trees healthy, administering proper care and promptly recognizing and reporting harmful pests, such as the emerald ash borer (EAB), an invasive beetle from Asia that targets and kills ash trees. Fall 2011 TreeKeepers classes begin September 10, at the American Indian Center, 1630 West Wilson Avenue, in Chicago. For complete information on the classes, and to view and download a copy of the Fall 2011 TreeKeepers brochure go to the Openlands website.

Participants in the seven-week program meet every Saturday morning for three hours of hands-on instruction in topics that include basic tree planting and care, species identification, and how to recognize diseases and pests. A low fee of $100 covers the cost of class materials. Financial assistance is available. Classes are taught by professionals from Bartlett Tree Experts, The Care of Trees, Chicago Bureau of Forestry, Chicago Park District, Chicago Department of Environment, and the Morton Arboretum, as well as other expert arborists. After completing the coursework, TreeKeeper trainees must pass field tests and a final exam—some institutions grant college credit for the class.

TreeKeepers classes are sponsored by Openlands.  Founded in 1963, Openlands protects the natural and open spaces of northeastern Illinois and surrounding region to ensure cleaner air and water, protect natural habitats and wildlife, and help balance and enrich our lives.

In addition to conserving land and waterways, Openlands conducts thoughtful research, advocates for sound conservation policies, and helps individuals and communities care for their open spaces.

Charlie's Gardening Tips - Now that Spring is Really Here . . .

By Charlie Ruedebusch, Head Gardener @ Cheney Mansion If you haven’t had time to go out and prepare your gardens or planters for the year, don’t worry. The season is just starting!

If your garden soil is heavy and full of clay (and whose isn't around here?), get yourself lots of compost and mix mix mix it into the soil. Hard work now makes for much easier gardening and happier plants for years to come. Add some slow-release, granular fertilizer into the soil as you mix in the compost (follow the package directions for amounts).

If you have planters and haven’t replaced the potting mix for a few years, buy new mix this year. Old potting soil tends to break down over the years (it is organic, after all). Some potting mixes have fertilizer already in them – if not, add your own slow-release fertilizer according to directions. Don’t use any topsoil in containers – it’s much too dense.

The weather we had this year reminds us that it does still get cold in Chicagoland in May!   While vegetables like peas, lettuce, radishes, and carrots, and flowers like pansies don’t mind cold weather and could be planted back in April, many other veggies and most annual flowers need warm weather to thrive. Tomatoes, peppers, and eggplants hate cold weather and cold soil, and are best planted after mid-May. Many expert gardeners don’t plant their tomatoes until Memorial Day!

If you’ve started your own seeds indoors this year (good for you!), or purchased seedlings from a greenhouse, it’s a good idea to “harden off” the seedlings before planting them in the garden. This just means setting them outside in the shade for a few days, and bringing them back into the house or porch at night. This gives the tender seedlings a little transition time to get used to the big wide world out there in the garden.

Late May is a great time to plant seeds of cucumbers, melons, squash, and beans directly into the garden. Cukes, melons, and squash plants will get big by the end of summer, so give them plenty of room in the garden.

You can snip off the spent flowers from spring bulbs, but not the foliage. The leaves are needed to make food stored in the bulbs for next year’s flowers. Lightly fertilizing the plants just after they flower (or earlier, just after they pop out of the ground) can’t hurt. While daffodils and hyacinths often come back year after year, tulips are fussier and tend to bloom only for a few years – it’s not you, it’s them.

You can make fall-blooming perennials such as mums, asters, or sedums bushier with lots more flowers by doing this simple trick. Pinch or shear a few inches off the plants twice in late spring: once in mid-May, and once in early June.

Now for the W word. Weeds are always with us. Keep on top of them when they’re small, and you’ll save yourself lots of work later in the season.

Enjoy the season!

Oak Park Conservatory Offers Green Thumb Workshops

Each spring, The Oak Park Conservatory at 615 Garfield Street, offers helpful workshops for all sorts of gardeners, from home owners to deck planters in condos and apartment building.   This year you can attend one of the following:

Gardening 101 - 3 Wednesday from May 11 to May 25, from 7-9 p.m.   The cost is $40 for residents and $60 for non-residents.

Composting 101 - Saturday, May 14 from 9:30-11:30 a.m.  $20 for residents and $30 for non-residents.

Care and Maintenance of Trees - Thursday, May 19 from 7-9 p.m.  $15 for residents and $22 for non-residents.

You can register online at www.oakparkparks.com or at the Conservatory.   See the calendar of events for more opportunities at the Conservatory.

Join the Park District Green Team

Join the Park District of Oak Park to help with the greening of our parks. We're looking for community volunteers who would like to help care for a local park and have a few hours to:

• work with park stewards to monitor and maintain biodiversity

• help monitor our trees for insect or disease damage

• remove invasive species from our naturalized areas

• help ensure green operations on all of our park lands

• improve the overall quality of our parks

PDOP Green Team Volunteers will work under the guidance of a park steward who reports directly to the Park District’s Superintendent of Buildings and Grounds. Interested Steward candidates should have a working knowledge of or interest in horticultural practices which might include gardening, prairie restoration and perennial plant and tree care.

The Green Team is currently focusing on the natural area in Field Park.

Call 708-725-2450 or stop by and fill out an application at the Oak Park Conservatory at 615 Garfield Street or the Park District Administrative Center at 218 Madison Street.

For more information on volunteer opportunities with the Park District of Oak Park go to http://www.oakparkparks.com/Jobs/volunteer.htm.

Submitted by Diane Stankeat 615 Gareld Street or the Park District Administrative Center at 218 Madison Street.