If you keep the leaves cut off so the seedlings cannot utilize sunlight to manufacture the nutrients necessary to promote growth they will, eventually, die. I find that works quite well with Maple, Oak, Pine, Black Walnut, and even Tree of Heaven, as well as other unwanted plants including Pokeweed.

No matter what kind of trees you have, you'll likely have tree sprouts when gardening anywhere near trees. In this yard, it's oak and pecan, some crape myrtle. I spend a few minutes a few times per week pulling them out while they are small and easy to pull. As we speak, it's raining acorns. It's much easier to keep control of these things consistently throughout the year than to let them develop to where you feel you want to use chemicals.

Are you saying your sprouts are in a bed or in the lawn?

They are mostly in one of my raised vegetable gardens. I'm not talking about a few here and there, there are hundreds if not thousands. As time allows I do pull and dig them up but more keep popping up every day. I guess I was just looking for an easy fix. Would corn gluten work if i time right?. I mostly plant transplants so using it wouldn't be a problem as far as that goes.