Question: What plant do flowers  used primarily as a flavoring and stability agent in beer that are grown on  long distance path of 108 mi in southeast England, from Haslemere in Surrey to Hamstreet in Kent?

full_context: Document 1: Coigneau: Coigneau is a Belgian variety of hop which was massively cultivated in the Flemish Aalst-Asse area near Brussels in the nineteenth and first half of the twentieth century. Because of the light bitterness the Coigneau was during a considerable period of time the favorite hop used for Lambic beer brewed in the Pajottenland region of Belgium (southwest of Brussels).
Document 2: South Cheshire Way: The South Cheshire Way is a 32 mi long-distance footpath running east–west mainly through Cheshire, England, though parts lie in Shropshire and Staffordshire. The western section from Grindley Brook, near Whitchurch, runs through farmland; the eastern section from Mow Cop, near Biddulph, runs through low hills. The footpath is waymarked with black and yellow discs inscribed 'SCW'.
Document 3: Maelor Way: Maelor Way is a key long distance footpath, running 38 kilometres / 24 miles from the Offa's Dyke Path National Trail at Bronygarth to the Shropshire Way, Sandstone Trail, Llangollen Canal, South Cheshire Way, and the Marches Way all at Grindley Brook near Whitchurch.
Document 4: Hops: Hops are the flowers (also called seed cones or strobiles) of the hop plant "Humulus lupulus." They are used primarily as a flavoring and stability agent in beer, to which they impart bitter, zesty, or citric flavours; though they are also used for various purposes in other beverages and herbal medicine. The hop plant is a vigorous, climbing, herbaceous perennial, usually trained to grow up strings in a field called a hopfield, hop garden (nomenclature in the South of England), or hop yard (in the West Country and U.S.) when grown commercially. Many different varieties of hops are grown by farmers around the world, with different types being used for particular styles of beer.
Document 5: Old Sarum Way: Old Sarum Way is a 32 mi long-distance footpath in Wiltshire, England that does a complete circle around Salisbury.
Document 6: Rye IPA: Rye India Pale Ale is a style of Rye Beer that has a strong hoppy character comparable to the India Pale Ale. The Rye India Pale Ale is a Beer style that uses malted rye grains in the mash ingredients. The addition of rye adds a tangy or spicy character to the beer. Its use has recently grown in popularity among American Craft Brewers but has been a traditional brewing grain for many eastern European breweries for many years.
Document 7: Daviesia latifolia: Daviesia latifolia, commonly known as hop bitter-pea, is a shrub in the family Fabaceae. It usually grows to between 1 and 3 metres high and has large leaves with a prominent network of veins. Clusters of yellow and brown pea flowers are produced between September and December in the species native range. The species was first formally described by botanist Robert Brown, his description published in "Hortus Kewensis" in 1811. It is endemic to eastern Australia.
Document 8: List of beer styles: Beer style is a term used to differentiate and categorize beers by various factors including appearance, flavour, ingredients, production method, history, or origin. The term "beer style" and the structuring of world beers into defined categories is largely based on the work done by writer Michael Jackson in his 1977 book "The World Guide To Beer". Fred Eckhardt furthered Jackson's work publishing "The Essentials of Beer Style" in 1989.
Document 9: Hesperolinon breweri: Hesperolinon breweri is a rare species of flowering plant in the flax family known by the common names Brewer's dwarf flax and Brewer's western flax. It is endemic to California, where it is known from three counties in the San Francisco Bay Area. It is found in chaparral ecosystems, often on serpentine soils. This is an annual herb growing erect to a maximum height near centimeters. Its narrow, linear leaves are greenish to purplish in color. It produces dense inflorescences of flowers with glandular sepals and five bright yellow petals. The protruding stamens hold large orange-yellow anthers. This uncommon California endemic is threatened by development of its habitat but its current status is not known.
Document 10: Eupatorieae: Eupatorieae is a tribe of over 2000 species of plants in the aster family. Most of the species are native to tropical, subtropical, and warm temperate areas of the Americas, but some are found elsewhere. Well-known members are "Stevia rebaudiana" (used as a sugar substitute), a number of medicinal plants ("Eupatorium"), and a variety of late summer to autumn blooming garden flowers, including "Ageratum" (flossflower) and "Conoclinium" (mistflower).
Document 11: Greensand Way: The Greensand Way is a long distance path of 108 mi in southeast England, from Haslemere in Surrey to Hamstreet in Kent. It follows the Greensand Ridge along the Surrey Hills and Chart Hills. The route is mostly rural, passing through woods, and alongside fruit orchards and hop farms in Kent and links with the Stour Valley Walk near Pluckley in Kent. The trail was opened on 15 June 1980 and is jointly managed by Surrey and Kent Councils who fully updated it in 2012 (route, waymarking, online guide).
Document 12: Wey South Path: The Wey South Path is a Long Distance Path in Surrey and West Sussex, England. For part of its 32-mile route it follows the banks of the River Wey and of the Wey and Arun Canal.
Document 13: Lambic: Lambic is a type of beer brewed in the Pajottenland region of Belgium southwest of Brussels and in Brussels itself at the Cantillon Brewery. Lambic beers include gueuze and kriek lambic. Lambic differs from most other beers in that it is fermented through exposure to wild yeasts and bacteria native to the Zenne valley, as opposed to exposure to carefully cultivated strains of brewer's yeast. This process gives the beer its distinctive flavour: dry, vinous, and cidery, usually with a sour aftertaste.
Document 14: Stevenage Outer Orbital Path: Stevenage Outer Orbital Path (STOOP) is a long distance path orbiting the town of Stevenage in Hertfordshire. Established by North Herts Ramblers Group, it is 27.4 mi long and is split into several sections, accessible via a series of links from the town. The route passes through Graveley, Walkern, Beane Valley, Datchworth, Woolmer Green, Knebworth Park, St Ippolyts and Little Wymondley. It was launched on 20 September 2008.
Document 15: Watling Chase Timberland Trail: The Watling Chase Timberland Trail is a 10.5 mile footpath in the Watling Chase Community Forest in Hertfordshire. It starts at Elstree & Borehamwood railway station, where it links with the London Loop, and goes mainly through farmland and parks. It passes through Shenley, London Colney and Colney Heath, finishing in Smallford near St Albans, where it links with the Alban Way.
ground_truth: Humulus lupulus