Inner Rind of a Fir Tree

The good folks at Brewers Publications were kind enough to send me Stan Hieronymus' Brewing With Wheat, which debuted just a few weeks past. If you are at all interested in beer, books like this one are catnip. As Jeff Sparrow did in his excellent Wild Brews, Stan begins with a historical overview. It passes through, as all brewing histories do, the caprice of law and geography that conspired to create beer styles. As if walking a cemetery, Stan reads off the names of the dead, including, much to my fascination, a deceased style from England--in the days before England banned the use of wheat in brewing (!)--called mum. The source he quotes describes it thus:
"To produce 42 gallons of mum start with seven bushels of wheat malt, one bushel of oat malt, and one bushel of beans. Once fermentation begins thirteen flavorings are added, including three pounds of the inner rind of a fir tree; one pound each of fir and birch tree tips; three handfuls of 'Carduus Benedictus,' or blessed thistle; two handfuls of 'flowers of the Rosa Solis' or sundew; the insect eating bogplant, which has a bitter, caustic taste; elderflower; betony; wild thyme; cardamom; and pennyroyal."
A few things spring to mind:
  1. Do brewers prefer bogplant rich with insects or free thereof?
  2. Would our native firs suffice as a substitute, or possibly the cambium of the Western red cedar, said to be edible?
  3. Beans?
In seriousness, I have long wondered if we could figure a way to incorporate local ingredients into beer to create something a bit more indigenous. I'm delighted to hear about this fir-rind business, and hope to inspire an experimental brewer to get cracking. Derek?

I'll have more from Brewing With Wheat as I read on. Meantime, I have already found enough of interest to recommend it, so if you are similarly fascinated by the history and art of brewing, consider picking up a copy.