Here's a very low poly Toony Tree I created that is game ready.
It is UV Unwrapped with a custom singular diffuse texture to color the bark and tree top.
Please note the UV Mapping is spiraled somewhat and this is to create the twisted bark effect on the trunk.
It has been tested and works perfectly in UE4 and Unity5.
If you like this free tree well enough consider buying my Pixel Tree 3-Pack to get 2 more trees for your project! You can get it over here - https://www.cgtrader.com/3d-models/plant/other/pixel-tree-3-pack today!