No. 10/September 11, 2020

Whiteflies
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 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 greenhouses.

Hover Flies
Hover flies (aka syrphid flies or flower flies) are likely buzzing about any nectar-producing flower in your garden this summer. They are excellent fliers, capable of flying backwards, forwards and hovering over their beloved flowers. They were abundant on my recent camping trip, likely because our camping site was near agriculture fields. They annoyed us as they constantly swarmed and landed on us, presumably looking for moisture and salts on our skin.

Fall Broadleaf Weed Control in Turf
Cooler temperatures are finally here. Winter annual weeds and cool season perennial weeds will soon be preparing for the long, cold months ahead. Now is the ideal time to control these broadleaf weeds in turfgrass.

Tubakia Leaf Spot
I received several reports of tubakia leaf spot on oak. This is a fungal disease caused by the pathogen Tubakia dryina. It is a common sight on oak trees late in the summer. All oak species are susceptible to this disease, but those within the red oak group are more commonly affected. This leaf spot is often associated with stressed trees, especially Pin oaks affected by iron chlorosis. Other potential hosts include maple, hickory, chestnut, redbud, ash, black tupelo, sourwood, sassafras and elm.

Laurel Wilt
Laurel wilt is a disease caused by the fungal pathogen (Raffaelea lauricola) that is vectored by the redbay ambrosia beetle (Xyleborus glabratus). This exotic disease was first detected near Port Wentworth, Georgia in the early 2000s. Since then, it has killed millions of redbay and swampbay trees as well as caused extensive damage to agricultural avocado groves. To date, Laurel wilt has not been detected in Illinois. However, laurel wilt has been detected in Kentucky, and has it the potential to infect two plant species utilized in our landscapes. You can view a laurel wilt distribution map via the following link: https://www.fs.usda.gov/Internet/FSE_DOCUMENTS/fseprd669956.pdf