autumn ecology ecosystem England english fall forest Great Britain green leaf leaves natural nature pond pool reflection Sussex trees water woodland border boundary edge exposed farm field hill hillside landscape moor moorland remote spring view wild bed calm countryside February peaceful quiet reeds river rural shallow tranquil chilly cold footpath slope snow snowy track tree Trek walk winter Alexanders Apiaceae cliff coast coastal Cornish cornwall edible flowers plant Smyrnium olusatrum Umbelliferae yellow conifers direction evergreens exercise path pines trail travel Betula birch deciduous sunlight trunks white clouds heath heathland meadow sky summer cumbria destination fell Lake district lane road route wall