Ammophila coast coastal coastline colonist Cornish cornwall dune England english grass Great Britain habitat marram natural nature plant sand shore stabilise dunes Caryophyllaceae Devon flowers little petals small spring stamens Stellaria stichwort stigma tiny verge white wild berries bush crataegus field fruits haws hawthorn hill landscape meadow red shrub South Downs summer Sussex access barrier clouds countryside entrance exercise footpath gate sky walk wooden abundance abundant Apiaceae Bedfordshire damp many profusion riverside umbellifer ancient architecture beak beast capital carved elements griffin gryphon historical monster mythical old statue stone wings