They will take dry flies, but they are not good at it. Their mouth is under slung for bottom feeding. Which means that just before they hit a dry they loose sight of it. Quite often you'll bring them up but they miss the fly.

The crisp clear winter's days, when the grass is crunchy underfoot, are not good grayling fishing days. What you really need are the days of "filthy" weather, drizzle and mist. As the weather gets colder they shoal up very tightly, and can be quite difficult to find.

There are a number of traditional wet and dry flies specifically for grayling. Generally they are smaller than the trout flies for the same river. The Czech and Polish nymphing methods were developed to target grayling, trout (and salmon) being a welcome by catch.

One thing that amazes me, whenever I am lucky enough to catch a large(ish) one, is how much lighter they are than trout. Length for length I would say 1/3 less weight.

I'm a big fan of the grayling and about August in a good season of trout fishing I find myself looking forward to the grayling fishing. It is a way to keep fishing later into the year. (Trout only being in season March to September) Unfortunately the nearest to me now are about 200 mile away. I will try to get a trip in for them this winter. Last year I had one planned, the day before I put my back out and couldn't go.

Cheers,
A.