I’ve been using Alder (Alnus spp.) tincture quite regularly as a lymphatic, pain reliever, anti-infective and alterative for a while now, and I’ve always been pleased with how gentle it is on the system, surprisingly good for the gut considering the tannin content and even nice tasting. I was unpleasantly surprised then, when I tried using the decoction for an infection. Those tannins really came out in the water-based brew and it was nearly enough to twist my tongue and intestines into one dry, puckered knot. Ugh. It was like black tea on crack, seriously.
So, for long term use, as a lymphatic or anti-infective I’d definitely recommend the tincture, but if you’ve got a bad case of the runs, are hemorrhaging or have a bit of organ prolapse it could be very useful. No wonder the natives used it for internal bleeding, that stuff could stop a cannonball from loosing even the littlest bit of fluid from a body. If you do use it for its astringent properties remember that tannins can inhibit digestive functions and shouldn’t be used in a strong form over an extended period of time. If you want a gentle, long term astringent try Raspberry leaf or Rose petals and save the Alder cones or bark for a more acute need.
On the other hand, Alder decoction mixed with Rose vinegar is just phenomenal on sunburns. And in the Southwest, that’s a very exciting thing to know.