THIS month’s Nature Notes were inspired by a trip to our local pub, The Hermit in Burley Woodhead. The pub has been rejuvenated under new owners and is once again a popular place for a pint. Rather appropriately, given its association with the brewing industry, they are growing Hops (Humulus lupulus) up the terrace where I am now sitting enjoying a drink.

Hops are vigorous climbers, always twining in a clockwise direction, it can shoot up to nine metres in length, and can completely cover other plants, perhaps explaining its specific name - lupulus, meaning ‘little wolf’. The English name Hop comes from the Anglo-Saxon hoppan meaning to climb.

The Hop plant is dioecious, just like Holly and Yew it has separate male and female plants. The male flowers are inconspicuous loose bunches. The female flowers are leafy cone-like catkins. These are initially also small and inconspicuous. As they develop, the yellow-green leaf-like bracts increase in size to produce the hops themselves which are harvested in September.

Hops were cultivated widely in the south-east of England. Harvesting the crop required a large force of seasonal workers until mechanisation was adopted in the late 1950s. Many families from the East End of London travelled down to Kent for a working holiday in September. Now, sadly, more and more hops going into British beer are grown overseas.

Although Hop is a native UK plant found in hedgerows, hops have only been grown commercially in southern Britain since the 15th century. Prior to this beer was flavoured with any number of herbs. Initially the addition of hops was not used for its bitter taste to counteract the sweetness of the malt, but because of its antibacterial effect giving the beer a longer cellar life. In the beginning there was a great resistance. Hence the use of the two terms - ale which was made without hops, whereas beer was made with them, although they are now used interchangeably.

What is causing the bitter flavouring and antibacterial effect? I pick a green hop cone and gently pull it apart, at the base of the leaf-like bracts are yellow grains. This is not pollen, don’t forget this a female plant, but lupulin glands. These produce essential oils and resins which give beer its bitter taste and the antiseptic effect.

To preserve these volatile oils, the harvested hops must be taken quickly to the kilns or oast houses, where they are gently dried before being taken to the brewery, and on that note, “Cheers”.

www.wharfedale-nats.org.uk