lacing facinates me. several years ago I had a bay standardbred mare. she was about 3 years old and she started getting BLACK lacing all over her back. looked like a black spiderweb. I did some research and heard they might fill in white and sometimes start out black. she started getting some grey hairs where the black lines were. I sold her not too long after so never knew if she turned into white lacing but it was a facinating thing.