You’ll find them affixed to the front of fishing vests, clipped to the brim of ball caps, and stuck to the underside of vehicle visors. They come in shearling fleece and high-density foam. Their purpose is to hold, to dry, to accumulate.

A fly patch can tell a story.

Fly boxes say a lot about the angler who uses them. Things are organized just so, even if there is little evidence of organization. Idealists fill their foam or silicone slits under controlled circumstances. They line patterns up by size, by color, by season, so as to match the hatch. Those who aren’t as concerned about such things just stuff boxes with what they have. It is pragmatic, but it works. With either approach, a fly box shows how someone thinks fishing might be.

Fly patches record real history.

The first flies of the day will be on there: maybe an ambitious nymph rig. So will be what was quickly defaulted to: a wooly bugger, a squirmy wormy, or a mop fly. Then you saw some fish rise, so you tried a BWO. Then an emerger. Then a crippled emerger. Then something that might be a BWO but you’re not sure what it really is. Each used fly ends up on the patch.

You can trace your day, your week, or even your season on your fly patch.

Flies might make it onto the patch because they are the flies you’ll always use. You have boxes upon boxes that you travel with, but they’re virtually unnecessary since only half a dozen patterns end up seeing the water. Hundreds of flies of all colors, shapes, and sizes make the journey with you, but only those few end up as part of the adventure.

A fly might make it onto the patch because you believed in it but it just didn’t work. It might be there because you didn’t ever believe it would work, but thought that you should give it a try because it sounds like something that should work. So there it sits, a reminder of a hair-brained idea that you could deviate from your norms.

A fly might make it onto the patch because it got chewed up by fish. It could have fallen victim to a lot of fish. It might have been destroyed by one big fish. It might not look any worse for wear, it just caught you a memorable fish that warranted retiring that fly. In that case, the patch is like a trophy case. You’ll see it, and you’ll remember.

Journals and photographs are great for documenting and remembering fly fishing  trips. But those are ultimately subjective mediums that interpret the facts of the day. A fly patch doesn’t lie. Full or empty, it records real history. It marks victories and defeats; hypotheses that panned out and plans that fell flat. Perhaps most importantly, it reveals your angling tendencies. If you want a real story of your time on the water, look at your fly patch.