Oh we got trouble, right here in our Green Tree cities, with a capital “T” that rhymes with tree and that stands for oaks, maples, elms, pines — and more.
Residents with mature trees in their yards have learned this summer that they don’t necessarily have it made in the shade. Their trees have taken a trouncing from storms, pests, rot and fungi.
Perhaps the surest sign of this came on a July weekend when a microburst storm took down massive trees in the area. More trees were toppled by a storm on Aug. 13. Earlier this spring, residents were sounding the alarm over pin oaks shedding yellow leaves.
“Trees are wonderful community assets, but they require some TLC and regular observation to determine care needs,” said Bill Ruppert, a Kirkwood horticulturist and owner of National Nursery Products. “Homeowners are wise to invest in trees, but it’s also wise to keep up with your investments.”
Ruppert recommends tree owners have periodic tree health evaluations by a certified consulting arborist. These should check on presence of pests, nutritional needs and safety conditions related to limb and branch structure.
“We are learning so much now about the importance of putting thought into what kind of trees we plant in order to head off a lot of tree problems,” Ruppert said. “It’s important to think about site and diversity when planting trees.”
In regard to site or location, Ruppert said trees like pin oaks natively thrive in moist river valleys. They do not do so well growing in high PH urban soils containing limestone concentrations, a condition common to Webster Groves and Kirkwood.
He said the loss of leaves from pin oaks earlier this year could be an indication of location stress. Or, the loss could be evidence of overactive squirrels that love to chew on leaf stems and branches as they build nests in the trees. Ruppert said planting a variety of trees can prevent a die-off from becoming a disaster.
The recent emerald ash borer attack on ash trees illustrates this. Extensive planting of ash trees in the past on Gateway Arch grounds has proven very problematic with the arrival of ash borers. A diverse stand of trees would have meant less tree damage and less rehabbing of the grounds.
Kirkwood’s Greentree Festival
Kirkwood residents may be surprised to learn that their annual Greentree Festival was founded in 1961 in response to an epidemic of Dutch elm disease. Many trees were lost in the city.
Residents were encouraged to plant trees to replace those being lost with trees sold at the fair for $1. Today, many of those trees are mature and grace the lawns and streets of Kirkwood.
“We periodically get a wave of tree losses for various reasons — elms lost to DED fungi, pines and spruces lost to pine wilt, needle cast and tip blight diseases, ash trees now being lost to borers,” said Bill Spradley, owner of Trees, Forests and Landscapes in Kirkwood. “What will be the next wave?”
Spradley said the answer to that question could be related to climate change, as Missouri falls get warmer and drier because of changes taking place across the continent.
Warmer, drier periods will be especially hard on pin oaks because their native habitat involves rich, wet, acidic river bottom lands. This problem is also apparent for river birch.
Climate change also seems to be bringing more windstorms and microburst storms into the area. These could be especially hard on red maples and are always hard on non-native Bradford pear trees. Some of the larger pin oaks also are vulnerable.
Spradley has a recommendation about trees that are in ill health due to root decay fungi, beetles such as the emerald ash borer or weather damage: Take them down now.
“It’s always better to take them down when there’s some life left in them,” said Spradley. “It’s dangerous, if not impossible, to climb on a tree and take it down when it’s dead or brittle. That will always cost more as well.”
Spradley added that when replacing the tree, look for varieties that are native and will thrive well in the particular location under consideration.
50 Trees In Kirkwood
Keep Kirkwood Green is the sponsor of “50 Trees,” a volunteer street tree planting program now in its eleventh year. Kirkwood residents have until Sept. 27 to submit a request for a free tree. The site must be within 15 feet of the street and without utilities below or power lines above.
Contact email@example.com or visit Keep Kirkwood Green volunteers at Booth 47 at this year’s Kirkwood Greentree Festival.
High On Oaks
Spradley, Ruppert and other tree lovers — such as Robert Weaver of Glendale’s Gateway Gardener, Carol Davit of Grow Native, Wayne Lovelace of Forrest Keeling Nursery and Guy Sternberg of Starhill Forest Arboretum — are all high on planting oaks.
They have produced a pamphlet entitled: “Plant an Oak! (But not a Pin Oak!)” Oaks native to Missouri are better adapted to the challenging conditions of urban and suburban sites with disturbed soils.
They recommend replacing dying trees with cherrybark oaks, northern red oaks, nutall oaks, overcup oaks, chinkapin oaks and more … but not pin oaks.
They add that in the spirit of planting for diversity, many other tree genera beyond oaks should be considered. However, oaks deserve priority when considering shade trees in this area.
For those residents still encountering yellow leaves dropping from their pin oaks, Spradley recommends sending samples to the experts for diagnosis. This kind of examination is available for many plants sick for various reasons.
The University of Missouri Plant Diagnostic Clinic has been serving Missouri since 1965. Clinic staff are available year-round to receive leaf samples for identification of insect damage or plant pathologies.