Trees like pines usually grow on the sloping sides of the mountains.Since most of the rainwater in such areas flows down the slopes, very little water is available to the trees.To conserve water,leaves are reduced to needle-like structures. They have a thick waxy coating on their surfranspirathe loss of water by tace to reduce transpiration.These trees are normally cone shaped and have sloping branches.This helps the rainwater and snow to slide off easily.The above pic shows the structure of pine trees,this will make u understand it more easily.
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