They might not have been pollinated. Sometimes the weather makes it hard for pollen to blow around, damp, rainy, and the female flowers don't all get pollinated. These ones fall off, just as you say. A few might have been fertilized and those ones will make full sized acorns. Sometimes a tree sets too may acorns too, and aborts a portion of them to lighten the load.

Not to worry -- small acorns are often aborted.

My 55' black cherry forms oodles of cherries, only to have almost all fall off halfway thru the season.

here in adrian MI ... if you are that GP ...

we are in week 4 of serious drought.. and that isnt helping the extremely long cold spring [during pollination time] .. on top of the harsh winter ...

so, to say.. what is the cause.. is near impossible ...

ken

I've seen some "buttons" on my oaks before, only a few, which never turned into acorns. I haven't seen them on the ground, but still green, in the canopy. Never turned to mature acorns. They were red oaks, Pins always red oak family oaks.

I love in the foothills of North Carolina and mine are dropping tiny o es as well.

This is normal. Many acorns "start" and then are aborted at a small size in certain years. I see it all the time. Happens with black cherry fruit too.

The ones dropping from my tree are barely formed and dropping like crazy. I live in north Georgia (Marietta).

same problem here, southwest Missouri, bunches of them. We did go thru a pretty good 2 weeks of no rain.

Mine just started this afternoon in Omaha NE. Only a few so far but they are falling like raindrops.

one of our oak trees drops these teeny ones nearly every year!. Lots of them now!

Our tree in north Georgia has finally slowed down!

North Central Illinois my pin oak is dropping them too. Been here 21 years, the first time it has done this. I guessed poor pollination.

I would just guess that the tree needs to conserve energy, or the stuff others here have said. My Chestnut oak used to have TONS of acorns every year, BUT, the last couple of years it has been either like last year, NO acorns at all, and this summer I can see a few here and there, and they just may abort before they become a decent size. And, I have NO idea why, I just can guess that the tree needs a break. I had seen NO catkins on it at all this spring, so, I am shocked it even has a few here and there this year so far. The deer have gotten used to the feast of acorns each summer. They still have the apples to eat though.

It shouldn't be a big problem. I hope not anyway. I have a Live oak that has had a couple of tiny buttons on it and it NEVER keeps them, or they never get any bigger, so, no biggie, that LO is NOT very old anyway.

This has happened here in Oklahoma several years in a row. They are so numerous that it is plague like, it hurts to step on them and they rain down in the pool, sink overnight and dye the plaster red brown. Although if you get them out the chlorine will remove the staining over a period of days. Take heart. Last year this happened. There must have been many thousand during July. In Sept. and October the very large tree nevertheless also produced many huge, glossy well formed acorns right on time. There is only one tree so I am not under an illusion.

I am wondering if I can compost the stunted ones as they must be nutritious to the soil. But I do not want to grow more trees. Surely they are still too immature to germinate ?

Composting them sounds like a great idea, just remember to turn the pile in case there might be a few that had sprouted. As you likely know, white oak family oaks acorns will germinate pretty quickly, and Red oak family acorns will not sprout until next spring.

Same thing happening here in northern central NJ. We had a ton of rain in July. Record levels. I see from alot of the comments it's happening in areas with drought too. The tress look healthy though.

Here in CT our white oak is dropping huge amounts- I can’t remember this happening before, but we have had huge temperature swings

Bsyenco, are they immature ones? I just wondered because if not, maybe they are dropping early, but they are viable.

Same happening here in PA. our Oak had a mast year 2 falls back, hardly any last year, but the last week has started dropping loads of brown ”nubs”. kind of like the numbers from the mast year (watch out on a windy day, they hurt!).

We have so many of those this year. My granddaughter (age three) loves them and collects them-she thinks they are so cute! Hahaha.