Tree / Na-palm grenades.

[mrudat]

The reasonable option

A capsule (grenade) that spawns trees.

The silly option

A capsule (grenade) that spawns 'Na-palm' trees.

The 'Na-palm' trees are palm trees that concentrate elemental sodium until they explode.

[spider-byte]

I've just created the first idea you listed:
https://mods.factorio.com/mod/Treenades

Thanks for the idea! I might credit you on the portal.

I might try the 2nd one as a separate mod.

[darkfrei]

I have same mod, but without update till 0.16: https://mods.factorio.com/mod/TreeBrush