In the fall, a number of factors come into play: the well-earned need to celebrate the harvest; the crisp, cool days; and a general feeling of plenty, so well symbolized by the cornucopia. A harvest beer filled the bill, as well as the mug. Such beers were iconic and much beloved, as evidenced in an East Prussian poem by Ernst Gardey:
O wonderful harvest beer,
You full celebration of freedom and desire!
Because of your beer tap, humans
Are weaned as babies from the breast!
Today, we are all familiar with Oktoberfest, or märzen beer, brewed in March for celebratory consumption in the fall. There is, however, another brewing tradition that has now all but faded—Erntebier, which translates simply as “harvest beer.” This is undoubtedly a very old and highly localized product, with brewers each producing their own variant.
By the end of the 19th century in northern Germany, erntebier had a somewhat cohesive stylistic identity, at least in Lower Saxony. Max Delbrück, in his 1910 Illustriertes Brauerei-Lexicon, describes erntebier as being a top-fermenting beer of 1049 to 1057 original gravity (12 to 14 degrees Plato), “very dark” in color, highly hopped, and lagered for several months at cool temperatures.
This sounds a lot like Düsseldorf altbier or the famous seasonal specialty, Sticke. The latter is simply a stronger version of regular altbier, brewed and served twice a year as a thank you to the breweries’ regular customers.
It is possible that erntebier is similarly just a dolled-up version of the regular small beer. We may never know for sure, but references to erntebier invariably describe it as “strong,” even at the gravities shown above, so that seems like a reasonable possibility. Geographically, Lower Saxony is just to the north of the North Rhine-Westphalia state where Düsseldorf is situated, so it would not be surprising to find similarities between alt and erntebier.