Watering a Redwood
The world’s tallest known tree is a coast redwood. It lives in the Redwood National Park of Northern California, and was almost 368 feet high the last time it was measured. The tallest tree in the record books was measured in 1872. It was a eucalyptus tree growing in Australia, and was 435 feet high. The question is: How does water get to the top of these tall trees?
Nobody knows for sure. Water doesn’t move in trees the same way that it moves in a simple tube, like a drink straw.
Here’s what we do know. Leaves have tiny openings called stomata. These let in carbon dioxide for photosynthesis, but water can get out at the same time. The loss of water in this way is called transpiration. As water escapes, more water moves up from the roots to replace it. Indeed, scientists have studied the sap, and found that something is sucking it up. They’re pretty sure that this sucking force is transpiration.
There’s more. Water molecules "stick" to each other and to the sides of the vessels through which they’re flowing. This means that one molecule of water can pull on another. Also, it means that the column of water does not break easily. Even if transpiration stops at night, sap can continue to flow the next day. It’s also the reason people should cut the stems of their flowers under water. This keeps the water flowing, and the flowers don’t dry out as quickly.
Without transpiration and the "stickiness" of water, tall trees like the redwood could not grow. This reminds us of what God said about the cedar trees of Lebanon:
The waters made it grow;
Underground waters gave it height,…
And its branches became long because of the abundance of water,…
Thus it was beautiful in greatness and in the length of its branches (Ezekiel 31:4-5,7).
Yes, tall trees are beautiful, and they provide homes for birds, wood for building, and good air to breathe. We can thank God for designing such a clever way to water them.