Drawing software for Windows/macOS/iPad/iPhone/Galaxy. Includes features for illustration, comics, and animation.
SpeedTree - SpeedTree is a powerful toolkit used to create 3D vegetation for video games, films, and animations.
Krita - Krita is a professional FREE and open source painting program. It is made by artists that want to seaffordable art tools for everyone. Concept art. texture and matte painters, illustrations and comics.
The Grove 3D - Model or grow adaptive 3D Tree models for use in CG renderings.
Adobe Photoshop - Adobe Photoshop is a webtop application for editing images and photos online.
Tree Studio - Easy 2D Tree Creation
GIMP - GIMP is a multiplatform photo manipulation tool.