No I don't think they are. They mean different things, exactly as you described.

Agreed: - tiring = physically exhausting - tiresome = mentally exhausting, boring or irritating

I agree with your usage, Su.Ki. I don't think they're interchangeable.

I actually would use "tiresome" this way. I'd be more inclined to use "tiring" for something physically tiring, like going to the gym or going for a walk. It seems I'm in the minority here though!

If it were within my power to conjure up an original thought, I would be more than pleased to offer it here. My only recourse was to consultmy friend, Mr Thesaurus, and here are the results: Tiring exhausting, demanding, exacting, taxing, arduous, difficult, hard to endure, boring, uninteresting, grueling, onerous, requiring hard labor, tedious, dull, monotonous, tiresome, irritating, exasperating. Tiresome irritating, exasperating, annoying, boring, dull, exhausting, laborious, monotonous, onerous, tedious, tiring, uninteresting, repetitious, plebeian, troubling, vexatious, wearisome, unmanageable socially, humdrum, uneventful, irksome, interminable, tedious, onerous, laborious, bothersome, disturbing, disquieting, exhausting, fatiguing, perturbing, distressful, Quite similar and not entirely distinguishable, which leads me to think that they may well be interchangeable. Just one man's opinion of moonlight; Donovan