My yard currently has a bunch of maple tree seedlings sprouting up. At first I didn't know what they were and it took a lot of googling "what kind of weed is this" to find out. Since maple trees aren't usually considered "weeds," it took a while to identify these plants.

Anyway, there's a lot of them. At first I was hand pulling them, but after I identified them I realized I could probably just mow them and, once they've had their sprouting leaves chopped off, they'll just starve.

But the relevant point of my story is that I learned that: a) apparently (some) trees really do just disperse ridiculous amounts of seedlings, many of which do germinate and at least begin to grow. b) since I've never seen Maple trees growing in dense thickets like bamboo, I'm assuming that the vast majority of seedlings die off (and in fact a lot of the seedlings are sprouting in clearly terrible conditions that won't make sense once they're just a tiny bit larger -- in shallow soil, in deep shade, etc).

I'm a bit less skeptical that drone-based seeding would work thanks to this, though have no opinion on if that's an improvement over humans doing the seeding in terms of success and efficiency.

By spreading bird feed.

Many species of both animals & plants use the "spray and pray" mechanism of reproduction. Create enough gametes and by sheer numbers, some of them will eventually turn into adults.

That doesn't mean this approach will be successful for artificial reforestation. The numbers are fairly different for ensuring that the total number of seeds cast off by a maple or pine tree over its lifetime results in one successor tree, vs. trying to recreate a clear-cut forest from seed stocks delivered by drone.

You mean in the ground? Squirrels:

https://blogs.northcountrypublicradio.org/allin/2017/11/12/f...

Birds and other animals.

Excellent point!