The tallest known coast redwood is 380 feet, and redwoods of the past were probably even taller.  Underground, the trees’ long roots wrap around the roots of other trunks, helping them stay upright amidst even the fiercest storms.  Standing tall is not easy for these towering giants, but simply reaching such heights is no small feat.  Like us, redwoods need water and nutrients to grow and survive, but imagine having to nourish a body that’s hundreds of feet tall.

“At the time that we discovered this, it just blew our mind.” 

–TODD DAWSON
Tree Biologist, UC Berkeley

FROM THE VIDEO

[Todd Dawson] One of the key questions when you start working on a redwood is, how does the water get all the way to the top of these enormous trees? It starts in the soil, where water is absorbed by this incredible network of roots into the tree and through this massive plumbing system, it's almost like a vacuum. The atmosphere is essentially pulling that water through the tree molecule by molecule through a series of really tiny pipes and it's a very long journey to the top. Eventually, the water hits the needles at the top of the tree and moves through these minute pores on the leaves back into the atmosphere and basically completes that cycle of water falling in as precipitation, taken up by roots, and moving all the way back through the redwood tree again.

But these leaves aren't just an exit door for water rising from the roots. Turns out that redwoods actually have a whole other way of hydrating themselves: drinking from the fog.

So at the time that we discovered this, it just blew our mind. We knew of no other trees being able to take water directly out of the sky. The coast redwoods of California are restricted to the coastal fog belt, and all the way back to the earliest part of my career I really wondered what the connection was between redwoods and the fog. It was this “aha” moment of just going, oh my goodness, this is maybe how they grow so large and how it is they're able to sustain this enormous body that a redwood tree actually is. 

We started putting monitoring devices up in the trees and the data that we were able to collect revealed that anywhere between 30 and 40% of all the water in the coastal redwood forest comes from fog. In addition, there's all this fog drip taken up by all of the other understory plants. Everything in the redwood forest is sort of linked to this fog absorption.