No, I would not speak of mowing someone's hair, but I would certainly speak of trimming the lawn.  <<chIp>> is glossed as "cut, trim (hair)".

But the English word trim doesn't mean "cut hair." It means "make shorter by cutting." The Klingon word chIp, however, means "make hair shorter by cutting." English trim can be applied to things other than hair, and is not even especially associated with hair.

When hair is cut or trimmed, it is shortened for aesthetic effect.  I don't know that Klingons have the notion of mowing lawns at all, and "Giving the grass a haircut" is certainly much more descriptive of what is happening than "Cutting the grass" would be to people who have no tradition of mown lawns.

Maltz gave us the phrase magh yotlh, so he at least understands the concept and could declare a "correct" phrase for it.

Whether "giving the grass a haircut" is a better description of the act than "cutting the grass" is subjective, and I'm not sure I agree that it's more descriptive. One relies on metaphor; the other is straightforward. And there are other reasons to mow grass than just for aesthetics: sports fields need to be mown if they are grassy; tall grass can support dangerous fauna, obstruct vision, and hinder the operation of vehicles; some animals eat hay. Since magh is a Klingon plant like grass, they must deal with it from time to time, either obliterating it or mowing it. Or maybe even using it decoratively.

I will continue with magh chIpwI' as the much more evocative

phrase.

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SuStel
http://trimboli.name