I created this to demo the addon Graswald. It works super well, it was a breeze to scatter vegetation, and the models are gorgeous. I also used Megascans for the logs and tree trunks. Rendered in Blender 3.0 Beta in cycles X with 4096 samples and OpenImageDenoiser at 3840x3840.
The addon has its own scattering interface which uses particle systems, but I have scattered similar assets from megascans in similar scenes with geometry nodes.