Plenty of these can be disturbed off our garden Cypress tree at the moment - the stunning little Argyresthia trifasciata. For someone just starting out (including myself!), the thought of identifying leaf-mines - the distinctive feeding signs left by a caterpillar on vegetation - can be a daunting task.
Indeed, there are many which are extremely similar to each other, require a hell of a lot of searching to find, or just can't be identified at all. Luckily, Argyresthia trifasciata isn't one of them and feeding signs can quite easily be found on the host Cypress by looking for discoloured brown leaves. Opening them up should reveal the feeding chamber which the larva lives in, and also its poo (resembling tiny brown sawdust) - known slightly more scientifically as 'frass'.