After finding little to no solid advice on how much dried Yarrow to use for some herbal beers I am developing, I recently embarked on an extended experiment.
Just kegged part one of this experiment, a light session herbal beer with Yarrow as the bittering addition. My idea was to create a small base beer I could later split and dry-herb in different ways.
I will post the full recipe soon and put a link here, but for the purposes of this thread I just wanted to share some results....
For this 10 Gal batch of 1.030 OG beer I boiled .4 oz dried Yarrow in a hop sack for 60 minutes. (Originally estimated for twice that amount but after I measured it out instinct told me it was way too much)
Result was a pleasant bitterness with a clean, lemon-like tartness, nothing harsh or unpleasant at all. I also noticed that final pH was considerably lower than that same recipe brewed with hops which I think contributes to this tart cleanliness, though I cant say for sure that the Yarrow is responsible for this.
Overall impression is that a little Yarrow really does go along way. For higher SG's I'd tick the Yarrow up only very slightly. This way the Yarrow, like any good bittering addition, allows for more interesting flameout / dry hop / aroma based flavors of your choice to shine though.
More info to come as these beers come though the pipeline!