Originally Posted by HoppyDaze
If its a cascade rhizome....it will be close to what the typical AA% for all other cascades. If you want to make a beer and absolutely must know the final IBUs for contest purposes...then see above.
I have Nugget, Saaz, Willamette, Centinnial and Cascade plants... I will use most of them in some bittering capacity. It will make good beer, and I like good beer.
Not to argue, but for the sake of reference: I've bought pounds of whole hops that varied by over 20% in bittering units from Hops Direct, from one year to the next, so if you are making an IPA, or even bigger beer with proportionally bigger AA, you can have vastly different results. Columbus comes to mind, being an all-around use hop, as it is both a big AA that can contribute significant bittering in early additions, or a flavor and aroma hop. Use this as an unknown to bitter and flavor in an IIPA and you'll need to cross your fingers...
Ultimately, it depends what hop you are using, what you are making, and what time you make the addition.
And as to the original 'can you' question: I just saw a pic of Papazian brewing with fresh home hops on his deck. You can do damn near anything in this hobby, and still make good beer. The difficulty in using them fresh off the bine is they contain significant moisture, so not only do you not know accurately how high of AA you have, you do not know what quantity of hops you are using, when they are not dried first.
In younger times, friends of friends of friends would want to rush their illicit harvest to the pipe, which invariably resulted in a green grassy flavor and guaranteed headache. It is with this recollection in mind that I personally only want to add dried home hops to my beers.