Hop

Humulus lupulus

Hop is an ancient crop plant whose fruit is used to flavour beer. This liana uses its hairy, twisting stems to twine itself around other plants and scramble upwards. The tips of young shoots are considered a delicacy: they may either be eaten raw or cooked like asparagus.

Description
Hop is a hardy climbing plant whose renewal buds over-winter under the ground. The shoots, which may be up to 6m long, feel raw to the touch. They display tiny thick and stiff hairs which enable them to climb and twine around other plants in a leftwards manner. The leaves are decussate, meaning arranged in pairs, and growing at right angles to those above and below and near the female flowerheads in two rows on the stem. They have a long leaf stalk and leaflets normally divided into 3-7 parts. Top of the leaf is dark green with stout thick hairs and feels raw to the touch. Leaf underside is brighter in colour. Hop is dioecious, e.g. there are both male and female sexes. The blossoms of the male plant form loose panicles while those of the (separate) female plant eventually develop into nut-sized, cone-like catkins.

Distribution
Originally, the species was naturally occurring in an area encompassing Southern to Central Europe and extending to Western Asia. However, it is now cultivated in all suitable climes around the world. In Austria, it is known in all provinces and up to montane zones. It is cultivated for the production of beer in the Muehlviertel area of Upper Austria and near Lake Constance. Hop is native to riparian forests, sites along rivers, in swampy Alder forests or other locations with moist and occasionally flooded soils rich in nutrients.

Endangerment and Conservation Status
Not vulnerable.

Ecological Characteristics
Each spring, the hop plant sprouts new growth from its underground roots and twines its way, always in a leftward direction, around all obstacles in its path. Often, the plant twines around the dead hop shoots from the previous year, producing so-called "hop braids". Without expending much energy in supporting tissue, as other trees and shrubs are forced to do, the hop can move through the darkness of woodland floors with ease. Male or female flowers appear only on the tips of shoots which receive sufficient light.

Special Characteristics
The female flower, the hops cone, is used in popular medicine thanks to its sedative, pain-alleviating and sleep-inducing qualities. Hops tea helps calm stomach and intestinal cramps and has a soothing effect. The tips of young shoots may be consumed raw or cooked in a similar manner as asparagus. The best-known use of the female fruit is, however, as flavouring in the production of beer. Lupulin – the bitter glandular powder separated from hops – lends beer its aromatic, slightly bitter taste and extends its shelf life. Minute amounts of the female sex hormone oestrogen are contained in the hop flower.