Well it’s not actually an oil painting 
Created in blender and rendered with Vray. Used post pro filters to give it an oil painting look. Hope you like it !
updated version:
old version :
It’s nice, but I see little story here. I also see the same tree over and over again. You should add more variety to the trees (the branches my be positioned differently and whatnot, but it still looks like the same tree) Also, the grass is too much fur and too little grass. Instead of using hairs, try modelling a few grass strands and putting them in vertex groups. You’d get away with furry grass if it wouldn’t make half of the scene, but like this it needs more detail. Also, grass isn’t uniform. Here it looks like the hairs are the same length, they shouldn’t be. And also, there are patches of dirt in grass (I believe you can get these by weight painting) Still, a nice render. Add some more story and it will be perfect!
EDIT: Actually, I put the image full size and the bark seems low quality. Try using bumps, speculars and deforms to give it more shape. Also, try using a bigger number of repeats for the texture, so the bark looks smaller. Still, good work!
Hey and thanks for your critique. I agree with most parts. I wasn’t planning to make it a “finished project”, it started as a test render to see how the trees look. It will definitely look a lot better if I change the things you said and I actually might!
If I watch the picture in full resolution, the effect of the oil painting looks nice! It makes a special structure on the surface.
Perhaps you could make it a bit rougher that the effect comes out better, if someone doesn’t watch the picture in full resolution. Additional to this modification, some missing details aren’t a too big problem - but on the other hand some details will be lost which are in the picture now (I mean mainly the bark and some thin branches).
General a nice variety to the normal posts!
Uploaded an updated version. It generally looks more high res and you need to look at the full size image to see the oil painting effects. Added some variety to the trees and changed the grass 