Mighty Ulmus
The cache, a small black-taped flip-top tablet pot, is hidden just off the public footpath running from around N 53 55.152 W 1 48.205 on Constable Road crossing a gravel track and up to N 53 55.098 W 1 48.212 on Hangingstone Road (just down from the Cow & Calf) - and under a huge Dutch elm tree. The nearest parking is roadside on Constable Road.
Elms are deciduous and semi-deciduous trees comprising the flowering plant genus Ulmus in the plant family Ulmaceae. The genus first appeared in the Miocene geological period about 20 million years ago, originating in what is now central Asia. They flourished and spread over most of the Northern Hemisphere, inhabiting the temperate and tropical-montane regions of North America and Eurasia, presently ranging southward across the Equator into Indonesia.
They are found in many kinds of natural forests. Moreover, during the 19th and early 20th centuries many species and cultivars were also planted as ornamental street, garden, and park trees in Europe, North America, and parts of the Southern Hemisphere, notably Australasia.
Some individual elms reached great size and age - often with a split trunk creating a vase-shape profile. However, in recent decades, most mature elms of European or North American origin have died from Dutch elm disease, caused by a microfungus dispersed by bark beetles. In response, disease-resistant cultivars have been developed, capable of restoring the elm to forestry and landscaping.
There are 30-40 species of Ulmus (elm) - the uncertain number arises from difficulty in delineating species, owing to the ease of hybridization between them and the development of local seed-sterile vegetatively propagated microspecies in some areas. Ulmus has been described as the most difficult critical genus in the entire British flora - 'species and varieties are a distinction in the human mind rather than a measured degree of genetic variation'.
Botanists who study elms and argue over elm identification and classification are called pteleologists, from the Greek πτελέα (:elm). As part of the sub-order urticalean rosids they are distant cousins of cannabis, hops, and nettles. For more fascinating information on elms, see here.
The tree under which the cache is hidden is likely to be Ulmus × hollandica 'Major', a distinctive cultivar that in England came to be known specifically as the Dutch Elm, although all 
naturally occurring Field Elm Ulmus minor × Wych Elm U. glabra hybrids are loosely termed 'Dutch elm' (U. × hollandica). It is also known by the cultivar name 'Hollandica'. 'Major' is considered to be either an F2 hybrid or a backcrossing with one of its parents.
The tree was a native of Picardy and northern France, where it was known from the 15-19th centuries as ypereau or ypreau. 'Major' is thought to have been introduced to England from the Netherlands in the late 17th century as a fashion-elm associated with William & Mary, the name 'Dutch Elm' having been coined by Queen Mary's resident botanist Dr Leonard Plukenet.
The epithet 'Major' was first adopted by Smith in Sowerby's English Botany published in 1814, identifying the tree as Ulmus major. The tree was formally recognised as the cultivar U. × hollandica 'Major' in 1962.
In areas free of Dutch elm disease to which it is highly susceptible, 'Major' often attains a height of up to 40m (131') with a short bole (trunk) and irregular, wide-spreading branches (as can be seen in the cache tree). In open-grown specimens, the canopy is less dense than that of the English elm or Wych elm. The bark of the trunk is dark and deeply fissured and, like English elm, forms irregular 'plates' in mature specimens, serving to distinguish it from the Huntingdon Elm (latticed bark), the other commonly planted U. × hollandica in the UK.
The leaves are oval, <12 cm long by 7cm wide, the top surface dark green and glossy, with a long serrated point at the apex.
The seed is 'rarely viable' or 'always sterile' and the tree suckers profusely from roots. In the south of Britain, 'Major' is commonly found as a sucker, sometimes in mixed hedgerows with English Elm. Large Dutch Elm sucker-populations have been found in south west Wales, Cornwall and along the south coast of England.
Owing to the ravages of Dutch elm disease, mature trees are rare in the UK, except in Brighton and Hove, East Sussex - The Level, in Brighton, alone has over 80 specimens in a double avenue. Other examples, including the TROBI (Tree Register of British & Ireland) Champion (27m high by 139cm DBH [diameter at breast height] in 2009, after pollarding) can be seen in the city along the London Road. The 38m high specimen at Leeds Castle was the tallest elm in Britain until it blew down in 2000.