Coastal areas have their own particular climate: there is less rainfall than there is inland, the sun shines longer and the wind is usually stronger with powerful gusts. The salt that the sea wind brings with it also means the trees are prone to dry out more quickly. Trees on the coast therefore need first and foremost to be wind resistant, tolerant to drought and impervious to salt. An additional complicating factor is that the soil is often barren and dry. Trees need to be able to put down deep roots to anchor themselves properly and get the water they require out of the soil. Fortunately there are trees that are very good at this and thrive perfectly well on the coast. As a result of the wind, trees in coastal area are shorter than their inland cousins and the crown may also be different. Close to the coast, in open dune areas, the crowns are usually asymmetric and the most common wind direction is revealed by their shape.