Is this 3 year old marked for some suspicious purpose.... Surely no horse would be thick enough to stick his head in weeds & rub it about till he has an attractive horn style design.
He probably thought it made him look hard tbh. It is his fantasy to be feared and boss everyone about, then he forgets and thinks he quite likes his mum after all:
I was talking to be sister about this subject this morning as Penny came over with a bizzare twist deisgn in her mane. I wouldn't worry, I'm not, she's just had her head in the bushes and been rolling. The others have discovered a bush somewhere in the field (which I haven't tracked down yet) which has those horrible spiky balls which mat into the mane. I found that some of my girls had turned into unicorns overnight!
One of mine came in with his entire forelock rolled up with sticky buds...it resembled an old-lady bun hairdo.....I was almost crying with laughter when I saw him at the gate.