No. 6/July 1, 2021

Sod webworm
Sod webworm is a common pest of turfgrass in Illinois. They are typically seen in mid-summer and cause brown patches in the turf. In favorable conditions, large sections of a lawn could become brown. In hot, dry conditions, like those we have seen in northern Illinois, sod webworm larvae thrive and have the potential to cause more damage.

Pellitory – A Newer Weed to Scout For
You’ve heard of purgatory. This is pellitory. It was nowhere and suddenly it is everywhere – including MY property, so now it’s personal. Perhaps you’ve noticed it too. In 2016, this largely unfamiliar weed was newly noticed to be growing rampantly all over campus in various landscape beds. Five short years later, it has made its way 15 miles south of town. I found it growing a few weeks ago for the first time all over a local, small town, community garden I assist with. Last week, I found a few plants growing deep within my windbreak. My guess is that birds have spread it there as this isn’t an easily accessible area and a bear to handweed so I trust my shoes didn’t spread the seed there. Regardless, if I’m seeing it in new places others likely are as well.

Iron Chlorosis and Manganese Chlorosis of Shade Trees
Are the leaves on your tree a little more yellow than you remember them being in previous years? You are not alone. I’ve received numerous reports of chlorotic trees from around the state. Chlorosis is a condition in which leaves turn yellow due to the destruction of chlorophyll or lack of chlorophyll production. In most cases, chlorosis results from a nutrient deficiency, either a lack of nutrients or the inability of the plant to uptake the nutrients. Iron (Fe) and manganese (Mn) deficiencies are two of the most common nutrient deficiencies seen in woody landscape plants. Pin oaks are especially prone, though we often see chlorosis affecting sweetgum, maple (especially red, silver and hybrid), and birch.