My fellow classmate, Patrick Pineda, contacted the 3D graphics company Elastic, to ask for their opinion of creating HO scale grass and vegetation, similar to the photo above from the Colorado Train Muesuem. Elastic, best known for their work on the Game of Thrones intro, did respond back to Patrick and gave us some great tips! Patrick was inspired to contact them after watching their Ben & Jerry's "Chocolate Fudge Brownie" commercial.
Link to Elastics website
Link to Ben & Jerry's "Chocolate Fudge Brownie" Commerical