Tree ID help please - Red Alder

I have hundreds of these little guys popping up.  They are on really,  really bad soil where a driveway was cut in years ago.  I'm hoping maybe they are a nitrogen fixer,  maybe a type of alder that are trying to repair the soil.  If they are, a lot of them will be moved to my food forest.  That makes it pretty important that I know what they are 😁

The leaf looks very much like alder. It is a nitrogen fixer and thrives in poor soil.

Where there's one there's a thousand. One of the best woods to put into a hugelkultur mound, because of the nitrogen and speed of decay.

https://permies.com/t/10609/Alder-nitrogen-fixation-native-tree

Looks like Beech to me. How do we distinguish between them?

This is my own red alder. Pretty clear picture for him to compare it to.

Of course there are different types of alder and all have a slightly different shape.

Yeah, the bud on your index finger would look like a sharp spike if it were Beech. Now I have to check my own.

edit: My 'spikes' weren't in evidence this late in the spring but were visible on branches that hadn't sprouted.

I'm not terribly good at IDing deciduous trees, but my red alders also grow in straight gravel, and look a lot like that.

Just what i was hoping for,  thanks.