Oak Apples (or Oak Galls)

Navigating this 2020 pandemic, I have made a point to get outside and walk in my neighborhood every day. Nature always brings a balance in life, I believe, and this is my way of balancing out the uncertainty we are all experiencing right now.

I began walking in mid March, and almost every day I have come across an interesting plant and/or animal. I have been diligent in taking my cell phone with me on my walks for photo ops. Actually, my cell phone is also my tracking device but I feel very fortunate I find something daily to photograph and research along the way.

One of the most unusual things I’ve found along my daily walks are oak apples – or oak galls. These thin-shelled, tan orbs about the size of golf balls are quite intriguing. At first glance, they appear to be something that grew from an oak tree itself – perhaps a fungal issue or otherwise. However, they are not derived from plant situations but, instead, from insect circumstances. The oak gall wasp, a very inconspicuous and small, hump-back insect, lays its eggs near oak leaf buds in early spring. Thereafter, a chemical reaction occurs during this egg laying process that miraculously transforms a leaf bud into a protective orb around the larva, making certain it survives without being eaten by a predator.

An interesting and odd fact is oak wasp larva do not expel any waste during this gall stage (they don’t poop) so the orb remains a very safe and sanitary place for the larva to develop. Once the larva transforms into a wasp, it bores through the orb wall and takes flight to start the process again next spring. (The wasps overwinter in the ground.)

If you see an orb on the sidewalk or in a yard below stately oak trees, most likely the larva has already emerged. Go ahead and pick it up and take a look inside. You will find web-like strings that kept the larva safe and centered in place until it was ready to escape.

Oak galls do not do a lot of harm to an oak tree unless they are inundated with them, so there is no need for great alarm if you see only a few on your tree (or on the ground).

Gall Wasp – Photo Compliments of Wikipedia Commons

While the oak gall wasp cannot be compared to a beautiful butterfly or moth, it does seem to be one of the more astute insects when it comes to protecting its young. And, that in itself makes this wasp quite a fascinating insect!

Until next time,


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