The annual hop harvest is about to start, and will take until early April to complete. New Zealand produces annually more than 800 tonnes of dry hop from about 20 varieties. Most is exported.
Hops belong to the same plant family as cannabis. Both can be habit-forming for different reasons - the hop for its wonderful aroma and almost oily richness and bitterness in beer. Hops have long been used to treat anxiety or insomnia (e.g. in hop pillows).
Some varieties are used in brewing for their aroma; others for the flavours they impart which range from citric, spice, pine, grass, floral to earthy characters. The amount of bitterness is determined by the variety used or when the hop is added during the brewing process.
Hop also helps to keep beer fresher longer. Its modern popularity dates back to the 18th century when it was put in English beer to help it survive the long voyage to the Indian colony - hence, the modern hoppy India Pale Ale.
The harvest is a good excuse to pour three hoppy brews from the United States, which produces about 30,000 tonnes from about 30 varieties, some of which impart twice as much bitterness as varieties grown elsewhere.
There are about 1600 breweries in the US. Towards the north of California, in Chico, is a relatively small one, Sierra Nevada Brewing Company, named after a neighbouring mountain range.
It has five brews, including a Pale Ale (5.6%) and a stronger Torpedo, an extra India Pale Ale which the label says highlights the citrus, pine and herbal characteristics of whole cone American hops.
Despite the distinctive aroma of hops, the pale ale is not overly bitter for those who are not out-and-out hop devotees. The Torpedo's bitterness, however, sits on the tongue for a long time, and this rich 7.2% brew will suit a cool autumn evening. The pair cost between $7.50 and $8 for a 355ml bottle - relatively expensive, but well worth trying one or two.
San Diego County Session Ale ($7.50) is the collaborative effort of two breweries (Ballast Point and Stone Brewing) towards the south of California and a home brewer (Kelsey McNair) whose recipe they liked. It was made as a way of featuring San Diego brewers.
A session beer is a British term for a moderate strength (no more than 4%) brew suitable for drinking over a long period. In the US, it is a beer of no more than 4.5%.
This 4.2% ale is the hoppiest (the aroma invades the room as soon as the top comes off) of the US trio and the most bitter, although not as rich because of the lower alcohol content.
I found the trio at Castle Macadam retail shop in Dunedin, but Sierra Nevada is available at the city's Inch Bar, Tonic and Albar.