I've just bought a 6'6" 3wt Primal Twig and have been using it on local forest streams. The image is typical of the more accessible water. The overgrowth is otherwise limiting. It's a bush bash.



I find the 3 wt DTF line a little light to project a short cast, which is often a necessity- and it collapses into a breeze on longer casts- which turns off fish in the slow pools.

The Twig is a slow rod, light and responsive. The fish on feel took me by surprise. Exciting. But I can't fish it as stealthy or as effectively as my 7' 2" rod, (The Princess, with a 5DTF), which probably has a limited life, so broken it is.

Can I trust my intuition to use a 4 DTF? The slow rod action and heavier line (ballistically speaking- reading another post) seems a better option for this fishing situation.

Trevs advice is excellent as usual. Id say that a 4DT may well serve better in your situation. Dont overlook all 9f the great "3wt" small creek lines, I have a feeling they might be just the trick for you. I have gotten great use out of a rio creek 3wt. Its a half line weight heavy, and a lot of the weight is near the tip of the line. As a result, it casts well (even with big flies) at close range, but generally is also fine for mid distance casts.

Thank you all. That elevates my confidence to up the line size. I haven't looked at the Rio Creek lines which appear to be a WF taper.

In essence, it's the weight of line from the rod tip.

I have a 5 DTF. I'll see how it feels. (But I guess line for line I will need to compare weights for a given length between the DT and WF lines.)

EDIT: Casting the 5DTF (an old Cortland 444 lazer) in the park felt solid and balanced. Short and false casts to 30' were effortless and accurate. Different rod. Glad I didn't run out and buy a 4wt line. I'll try it out on the water later in the week. Interested to see how it goes with an indicator and nymph on a dropper.

If we were willing to cut a rio creek 3wt up and weigh each foot, I wouldn't be suprised to hear that the first 10 ft are equivalent in weight to 10ft of a 5wt line. The bennefit to something like an "aggressive" 3WF is that the line weight after the first 10 ft falls off allowing for longer casts and making the line slightly more versatile. It does seem like the wilder a wf lines taper gets, the less likely it is to feel right when casting. If all casts are within 5 meters anyhow it probably doesn't matter if you use a fancy 3wt with a heavy head or a regular old dt5.

I find lines with bizarre weight distributions interesting, but I have found that they often are not as sure of a bet as something like a good old dt line.

I love fishing glass rods because they can be fished "under or over lined". Over line to make roll casts easier and under line to suspend more line in the air. You can go down two line weights or up two weights.

The best answer is for you to take a couple different weight lines when you go to this creek, try them out in actual fishing situations, and then you'll have your answer.

You should check out Barrio fly lines Small Stream Special. It cast like a half size heavy line. Prices are great and the service is exceptional.

Whether or not a given rod is suitable for drastic over-lining depends on some different factors. First of all, some rods may not have been accurately labeled by the manufacturer, so what was labeled a 3-weight may actually be a 4- or 5-weight. Some tapers are more forgiving than others and will be easily cast with a line that is one or two weights lighter or heaver. It can also depend on one's casting skills. Leader design also enters the equation.

My main objection to the practice of over-lining for use on small, brushy streams is that when it comes time to cast beyond 25 or 30 feet, the rod can just run out of gas, so to speak. I would rather have to work a little harder in close and have the flexibility for a slightly longer cast if necessary.

Whether or not a 3-weight rod is suitable for dry-dropper use depends a lot on leader design and fly size. For such usage, my go-to design is basically the old Ritz formula (60% butt - 20% stepping down - 20% tippet), The dropper, onto which my dry fly is tied, is simply a long tag on the last blood or double surgeon's knot, with a small nymph going on the point (the end of the tippet). With that set-up, it's no problem to use a # 12 or #14 dry on the dropper and a # 14 or #16 nymph on the end of the leader. My go-to terminal rig consists of a small nymph or soft-hackle wet on the dropper and a small (#10 or #12) streamer on the point. Either way, a wider loop is needed. Otherwise, the resulting tangles are not a pleasant experience.

Trev very well said definitely important to keep in mind when pairing your rod/line

Every now and then I build a fly rod that, even with twenty-five feet of line beyond the rod tip, begs for one line weight higher than the prescribed line weight. I'm presently considering deconstructing a rod that hasn't even reached the stream yet in order to salvage valuable parts.