Dry climate and water adaptations

Bristlecone Pines are very slow growing and long lived trees, that grow in a very dry and tough climate. The White Mountains are well known for their extreme climate. (http://articles.latimes.com/2011/jul/10/travel/la-tr-bristleconepine-20110710) Says that wind speeds often reach up to 100 mph, and temperatures are ever changing and can often drop below zero. 10,000 ft up in the mountains usually doesn't even get a ft of rain each year. According to (http://www.fs.fed.us/database/feis/plants/tree/pinlon/all.html) the trees are incredibly drought tolerant and can survive in poor rocky soil and extreme conditions because of their thick bundles of waxy, thick modified leaves (needles), which are good for avoiding water loss, can photosynthesize effectively for over 35 years. They also have a very shallow root system in order to maximize their water uptake. Since their needles are able to maintain a low leaf water potential, the trees internal water stress also remains low. This is how the Bristlecone Pine is able to survive for thousands of years in one of the most harsh climates for trees.