Leaves and frost damage

Some trees may be showing damage from the late frost much of Illinois had in May for several months to come as well as diseases that pop up during the rainy, cool spring weather. Watering during the hot dry months of summer will help these trees back to being a beautiful specimen.

If you didn’t know, we are cultivating invasive trees in backyards and urban settings. Tree-of-heaven (Ailanthus altissima) and Amur corktree (Phellodendron amurense) are outcompeting surrounding plants and invading natural areas contributing to the loss of native species in Illinois. 

Callery Pear on forest edge - Photo by Chris Evans, University of Illinois Extension

Do you see those beautiful white flowering trees lining the streets and backyards? These delicate white blossoms, made brighter by the months of winter endured, are actually an environmental hazard to the Illinois wilds. Callery Pear season is upon us.

diagram of branch bark ridge and branch bark collar

Like a scene from an old western: with a pair of sterilized pruners, and her boots, horticulturists Kelly Allsup walks up to the newly planted English White oak hybrid. Her sole intent of increasing the life of an urban tree. She walks around the tree, looking it up and down. The goal of pruning is to remove branches that will cause structural problems in the future, reduce competition of the central leader, and keep a balanced canopy. Kelly is ready to prune.  

holiday decor harvested from backyard

Decorating with fresh greenery is a treat for most gardeners getting ready for the holiday festivities. Some buy greens from a local garden center, but did you know you can harvest branches from evergreen conifers to use in your holiday décor?

Last week's high temperatures and our limited amount of rain is making gardeners' number one job watering.

Even though we have gotten some much-needed rain for the flowers and the trees, consistent watering throughout the season is very important. "Drought stress" occurs with limited water and very high temperatures. Plants are unable to make food and cool themselves. Drought stress symptoms are reproductive failure, slow and reduced growth, change in leaf color, browning of leaves, leaf drop and susceptibility to insects and diseases.

Maple anthracnose, via U of I plant clinic

If you are spending more time out in your backyard this week, you may have noticed some of our central Illinois trees are super ugly this spring. Maple leaves have black splotches, sycamore branches are falling to the ground and ginkgoes leaves are sparse and crinkled. All these symptoms are tree issues that link back to the cool wet spring and late frost.

Maples are suffering from fungal diseases like anthracnose and maple leaf blister. 

Hedge Apple Woods, Bloomington, by Rick Tindall

In this time of social distancing and limited activities, enjoying nature should be made a priority for all who need a bit of stress release. Have you bathed in the forest lately, hugged a tree or had a therapy session with an oak?

Bronze leaves of Tree of Heaven

In the world of landscaping, trees are the backbones of the landscape. They are permanent structures that have stately features, shade our homes, provide spring floral displays, and some amazing fall color. There are, however, some trees that just behave badly. You’re likely familiar with maples that drop their helicopter seeds (known as samaras) all over the neighborhood, sprouting up scattered shoots in our lawns and flowerbeds—hard to call this a bad tree with the fun they bring to children, but a nuisance to be sure.