Subject: What are these spots?
Location: Red Creek, NY
September 19, 2013 12:34 pm
Every fall we see these funny looking things on our oak tree leaves. Our class would love to know what these things are. Would you be able to help us figure this out? We are not sure if it is an insects eggs , fungus or what they are? Thank you Red Creek ABCD Preschool class.
Signature: ABCD Preschool
Dear ABCD Preschool,
These are Galls, which the University of Minnesota Extension website defines as: “abnormal plant growths caused by various organisms (insects, mites, nematodes, fungi, bacteria, and viruses). ” There is great diversity among Oak Leaf Galls which you may see on the Missouri Botanical Garden website. Many Oak Leaf Galls are caused by tiny Wasps in the family Cynipidae, and the images you supplied look somewhat like the photos posted to BugGuide of Galls produced by the Gall Wasp Callirhytis furva. The Gall is produced on the leaf and the larva remains inside the Gall, feeding on the growth which does not harm the tree. While we can’t say for certain we have identified the species correctly, we are relatively certain the Galls in your photo were produced by a Gall Wasp in the family Cynipidae, a group of insects studied extensively by Alfred Kinsey before he turned his research to Human Sexuality in the mid twentieth century, however that might be too much information to provide for your preschool children.
Thank you so much for your help!! My one little student has asked me to check for your reply all morning! As soon as he is awakes from his nap I will share this with him 🙂
Hello I am sorry to bother you again. My student, Emanuel keeps asking what you look like. Would you be so kind as to send him a picture? He is over joyed that you answered his question!
Thanks ABCD Preschool
Daniel, who responds to all the questions posted on What’s That Bug? has a photo posted on The Bugman of Mount Washington link.
Ok thank you so much! I will show Emanuel Monday morning!