Update - 2 Oct 2019
For the competition I wanted to capture the yew trees that I love to marvel at on summer walks.
The Yew trunk is sculpted in blender, the Bark textures are made using substance designer, and then applied to the bark inside Blender using Blender 2.8's Shader graph.
The leaf textures are constructed in shader graph, using a free program Materialize, to create the various maps from some photos I took of real life yew leaves. The leaves are distributed around the tree using blenders particle system, three hair systems specifically, one for small medium and large branches.
The above screenshots show the sculpting and construction of textures, for the trunk.
In total the project took me around 40 hours plus rendering time. I wanted to add some background trees, but it was getting so slow to render on my low end hardware, so I couldn't, even preview my changes, so i ended the project here.
Only external resource used is the HDRI which is from HDRI Haven, Listen as "Epping Forest 02".
Thanks for looking!
Shader Graphs for leaves, and bark.