Can a material "design" be copyrighted or off limits for commercial use?

So I saw this UE4 tutorial online for dressing a scene (mainly landscapes). I was rather impressed with the landscape material used so I set off to try and produce something similar. The tutorial did not disclose how the material was made. Well after a lot of research and time I’ve been able to produce something with a similar quality. I’d like to make it an auto material and sell it on the marketplace in the near future. What I would be concerned with is the similarity between my material and the tutor’s. Again they are not identical, but I wonder if that doesn’t matter. In both cases (mine and the tutors) the material is based on nature (forest floor), so it would make sense that the results are similar. Maybe I’m just overthinking this. I just don’t want there to be any issues down the road if I decide to sell it.

Could there be any issues if the tutor noticed similarities in the design (assuming he uses the forums and market place)?

Edit: Also, I wouldn’t want there to be any issues for the end user either, if the material was used in somebodies game and what not…

Rarely would the circumstances be a copyright issue. Really the only way where it would be a copyright issue is if it replicates a copyrighted graphic, like a cloth pattern. Another issue would be if they coded a shader to do something unique.