No. 12/September 22, 2021

August 2021 Plant Clinic Sample Summary
Summary of ornamental, fruit, and vegetable samples diagnosed August 2021.

In the coming weeks, you may notice a cloud of tiny white specks emerge from plants in your yard. These tiny insects are whiteflies. While they have the word “fly” in their name, they are actually more closely related to aphids, scales and mealybugs. Like aphids and scales, they suck fluids from plants with straw-like mouthparts and produce sugary, liquid droppings called honeydew. In large populations, they can become pests of vegetables, ornamentals and plants in greenhouses.

Poison Ivy
As a parent, a gardener, and a weed scientist, I try my best to teach my kids about certain weeds – when they will listen. One species that I always point out to them when we come across it while hiking is poison ivy. As a good mom should, I then tend to overreact a bit if a young, bare leg accidentally touches it. They know the phrase, “Leaves of three, let it be,” and my kids are good at questioning plants that look like poison ivy. What I apparently hadn’t explained well enough to my son was about the oil and how easily it can spread.

Septoria Leaf Spot on Dogwood
I recently came across a planting of midwinter fire blood-twigged dogwoods heavily damaged by septoria leaf spot, a common fungal disease of dogwoods in our area. Several Septoria species infect dogwoods. The bloodtwig dogwood (Cornus sanquinea) is a host to Septoria cornicola and Septaria cornina, with the latter more common in North America (Farr 1991).

Household Hazardous Material Collection Events Scheduled for Fall 2021
Now is the time to get rid of any old or unwanted pesticides in your chemical storage area. The Illinois EPA one-day household hazardous waste collection schedule has been released to the public. Please note, all one-day collections require pre-registration. More information can be found below. Here are a few options you have for disposing of your old or unwanted pesticides: