Reaching heights of over 100 meters, Californian sequoias tower over Earth’s other estimated 60,000 tree species.
Growing in the misty Sierra Nevada mountains, their massive trunks support the tallest known trees in the world.
But even these behemoths seem to have their limits. No sequoia on record has been able to grow taller than 130 meters –
and many researchers say these trees won’t beat that cap even if they live for thousands of years to come.
So what exactly is stopping these trees from growing taller, forever? It all comes down to sap.
In order for trees to grow, they need to bring sugars obtained from photosynthesis
and nutrients brought in through the root system to wherever growth is happening. And just like blood circulates in the human body,
trees are designed to circulate two kinds of sap throughout their bodies – carrying all the substances a tree’s cells need to live.
The first is phloem sap. Containing the sugars generated in leaves during photosynthesis,
phloem sap is thick, like honey, and flows down the plant’s phloem tissue to distribute sugar throughout the tree.
