hau Louis, one of the most overlooked first bush/shrub succession plants is called Coyote Bush (Baccharis pilularis), it is a nitrogen fixing shrub that will form shade in the summer as well as attracting pollinators late in the year (allowing them to boost their honey stores for winter).
The most interesting thing to me about this plant is that while the locale is listed as the west coast, it can be found all over, as far East as West Virginia.
We have it all over Arkansas as volunteer plants and they seem to live around 12 years before they die and become a source of rotting wood for the soil.
This shrub (actual classification) does lots of good things for the soil it grows in, including mycorrhizal fungi (arbuscular) introduction.
Be aware though that the seeds are wind borne and the germination rate is fairly good for these seeds.
The wood does pretty well for use in wood burning stoves and fire places when dried.
The shrubs can be coppiced for additional fire wood, (it carves fairly well when fully dried too).