Kansas State University

(By Megan Kennelly, KSU Plant Pathology; and Jared Hoyle, KSU Turfgrass Research and Extension)

There is a midge that is having a “bumper year” on oaks. There are
actually 2 kinds – one that causes swellings on the veins, the other
rolls the leaf margins inward.  You’ll see the margin-rolling one in the
photo below.

Then, there is a small mite that parasitizes those leaf-rolling midge
larvae. Now here is the bad part – those mites also bite people, leaving
a very itchy spot. It itches more than a mosquito bite and often has a
little pimple in the middle.

I sent some over to Entomology and they confirmed presence of itch mites
in the midges in some of my leaves. I’ll attach Eva Zurek’s (KSU Entomology) pic of a midge
with and without a pregnant female mite on it – you’ll see the round
swelling.

I’ve seen the midge activity in pin oaks all over town this year,
including my own tree.  My husband and I have a bunch of the bites, and
so do many of our neighbors. I’m guessing they blew out of the pin oaks
in the neighborhood while we were all out enjoying the nice weekend
weather. [Somehow, luckily, our son only has 1 or 2. Whew!]

Here is more info:

http://www.ksre.ksu.edu/bookstore/pubs/MF2806.pdf

There were some outbreaks back around 2004-2005. I’m hoping there is at
least another 10 year gap until the next outbreak, because these bites
are nasty!

Also, check out the previous blog post about itch mites….

https://blogs.k-state.edu/turf/itch-mites/