When you drink a soda with a straw, do you ever blow back through the straw and make a bunch of bubbles?
That’s a simple way to understand the complex system used by some plants, like sagebrush, to survive through wet and dry periods.
Sagebrush have a main root, called a taproot, that extends deep into the ground. They also have other roots spread out closer to the soil’s surface, called lateral roots. When the ground is wet in the spring, the lateral roots may get overwhelmed with water, so they “blow” water back down the taproot. In the middle of the summer when the weather is really dry, the lateral roots “suck” that springtime moisture back up from the taproot where it’s been stored. This helps keep the sagebrush leaves alive.
This circulation of water in plants is called hydraulic redistribution or hydraulic lift, although the water isn’t just lifted, it can move in any direction.
Such an adaptation has helped plants like sagebrush survive in what can be very dry areas. The tiny plant roots near the surface of the soil will even “sweat” water into the dirt to keep tiny microorganisms alive. Microorganisms are so small that some are only a single cell, yet they are necessary for a number of things, including providing food like nitrogen to plants.
Think about that the next time you walk through a field of fragrant sagebrush, but you won’t hear the plants making a noisy sucking sound like you do sucking through a straw when your drink is all gone.
— Brett French,
Gazette Outdoors editor