First trip to the zone: Cleared orcs and bownies with my 85 bard. With Selo's, tracking, and forage I could get things done pretty fast. After 30 minutes in BB looking for skunks (only found 3 in the whole zone) I spent 30 minutes in LFay. The result was a complete waste of time... not a single berry off of probably 50 kills.
Second trip with my rogue: Cleared all the orc camps, the brownies, and then camped the faries for an hour. At least 250 kills total - at 98 it only takes one arrow and with the new loot system auto looting for me it goes real fast. You dont have to move, just target, shoot, target, shoot.
The result? One stinking sylvan berry. At this rate, collecting 40 berries for the 20 drinks for the 16th anniversary Pub Crawl event will take 60 hours. I was foraging at the same time too and did not get any from forage. And no, i was not eating them, I had food in my top slot first bag.
Third trip decided just to focus on orcs and brownies. That helped a little, I averaged about 7 an hour but most of those were from orcs. So just focusing on orcs, with a tracking ranger, running across the zone and picking up brownie scouts along the way, auto-foraging the whole time with occasional double forages, the best I could do was about 10 an hour. Good luck, its too bad this is the very first task in the Pub Crawl because it will deter a lot of people from doing it.
This can also be found on brownies in LFay. The scouts and the outcasts. Didn't kill any other brownies, so I don't know. 1:3 brownie scouts had one, and very few of the outcasts did, also.