Boston Beer's Pumpkin Smashing Bud, Coors

In recent years, Anheuser-Busch's Jack's Pumpkin Spice Ale and Molson Coors' Harvest Moon Pumpkin ale have gone head-to-head with such microbrews as Brooklyn Brewery's Post Road Pumpkin, Shipyard Brewing's Pumpkinhead Ale and Sarnac Pumpkin Ale in a seasonal showdown for shelf space. This year, however, Boston Beer's Samuel Adams line has added its Harvest Pumpkin Ale to the fray just as the big brewers struggle for stability.

Boston Beer's Samuel Adams line has added a Harvest Pumpkin Ale to an already crowded pumpkin-beer market.

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It's only available three at a time as part of a seasonal 12 pack, but the beer press has loved it. Beer Advocate readers rate it a B+ and RateBeer gives it an 89 out of 100. That's the same score Beer Advocate and RateBeer readers gave the revered Dogfish Head Craft Brewery's Punkin' Ale and just shy of the A- and 98 rating each site gave to Southern Tier Brewing's Pumking -- the unspoken gold standard of all pumpkin ales. Jack's Pumpkin Ale and Harvest Moon, meanwhile, take home a C- and C+, respectively, and a 24 rating.

It's just the latest reminder that, when battling among the microbrews, the two big brewers often find themselves overmatched. A 2.2% drop in U.S. beer sales between 2008 and last year scarcely scratched the nation's nearly 1,600 craft breweries who, according to the Brewers Association, saw volume bubble up 7.3% from 2008 and sales pour in at an increased 10.3% from the year before.

Those numbers have held this year, as a 2.7% drop in overall beer sales in the first half was accompanied by a 9% increase in craft beer brewing volume and a 12% increase in the little guys' sales. That took some of the fizz out of Anheuser-Busch, which lost 0.1% market share last year, according to Beer Marketer's Insights.

That may not sound like much, but it was accompanied by 2.15 million fewer barrels of production. By comparison, that was a 2% decrease for Bud when a 2.8 million barrel decline in the same period was a nearly 10% loss for imported brews. Boston Beer, meanwhile, produced little more than 2 million barrels last year.

Even when the MolsonCoors soaked up A-B InBev's 0.1% market share, it dropped production by 1.1 million barrels. Boston Beer, meanwhile, increased its production 29,000 barrels last year and has bloated its output by 35% in five years.

But can a pumpkin ale that took root as an employee favorite at Boston Beer's Halloween parties really grow an entire brand? Let's put it this way: Boston Beer's market share is 0.9%, leaving 99.1% of the market untapped... as it were. It has three brewing facilities, none west of Ohio, and more than 20 varieties. That relative smallness (Boston Beer is still the second-largest craft brewer by volume behind Pennsylvania's Yuengling) and breadth of offerings is part of the reason Boston Beer's share price has more than tripled from $19 early last year to just above $70 today, and its market cap stands at just over $1 billion -- well below AB InBev's $100 billion but way above the $111 million cap of the Craft Brewers Alliance , which makes Red Hook, Widmer, Goose Island and Kona and is partially owned by A-B InBev. It's growth that's being savored by drinkers, investors and brewers alike.

"I drink lager almost all the time, but there are times when I want a pumpkin ale and there are times you want anything else for that moment," says Bert Boyce, a brewer at Boston Beer's research facility in Boston. "I think it comes down to the fact that we're riding this wave -- and I love being on this wave, it's what gets me up in the morning -- of what can we do next."

Yes, Boston Beer's ingredients tend to be more expensive -- the pumpkin in Harvest Pumpkin Ale comes from a small puree maker in North Carolina. Sure, it and other craft brewers still face an enormous challenge from big brewers willing to flood the market with crafty clones such as Budweiser American Ale, Bud Light Golden Wheat, Shock Top and the entire Blue Moon line. But even the smallest brewers are experiencing big growth, with Dogfish Head growing from 30,000 barrels in 2005 to more than 97,000 today, California's Stone Brewing skipping from 34,000 barrels five years ago to 99,000 last year and Colorado-based New Belgium exploding from 370,000 barrels to 583,000 in just half a decade.

"The fact that we're releasing so many new beers says that the craft brew community is as tight as it's ever been and that craft brew drinkers are as demanding and also as happy and fulfilled as they've ever been," Boyce says. "We are in the business to provide the perfect beer for the perfect time."

Right now, it's time for a pumpkin ale.