Trees use a straw like mechanism to pull water up to their tip. This pull of water in trees is created by a phenomenon known as
transpiration
Transpiration is the process of evaporation of water through tiny openings in leaves known as stomata. This evaporation creates a suction pull as when you drink any fluid using a straw. This suction is strong enough to pull water high up to the tips of even the tallest of trees. Transpiration also helps in cooling the plants.