’Tis the time of year to appreciate the value of roots

Geophytes are plants that store food underground. They include bulbs, corms and rhizomes, which are underground stems that store carbohydrates to sustain plants through periods of dormancy — usually periods of extreme cold weather or drought. Tap roots, which perform the same function, are also geophytes. That’s lucky for both humans and animals since plant energy storage containers make great foods, both savory and sweet, to also get us through the harsh weather.

This time of year, most of us associate bulbs with the gaudy flowers of amaryllis plants. But many of them are also on the table in the form of onions, shallots and garlic. Each of these bulbs is comprised of layers of scales that would become the foliage of the living plant.

Tubers are another variation on the underground storage stem. Potatoes and sweet potatoes are most familiar in the U.S. Cassava is the mainstay tuber in much of Africa. It’s most familiar here when it’s processed into tapioca, a thickener and dessert ingredient. Many of these tubers are native to South and Central America and were only introduced to the rest of the world in the 16th century. That they quickly became mainstays of cuisines around the world shows how much the calories from plant starches means for human survival.

Corms are another form of underground storage stem. The most familiar of these are the crocus bulbs that go into gardens in the autumn. But water chestnuts and the taro used to make poi are edible corms.

Another type of underground storage stem is the rhizome. The most familiar for northern gardeners is the iris. But rhizomes also make their way into our kitchens. Ginger is probably the most popular. Turmeric, another member of the ginger family, is also a popular addition to many Indian dishes.

The last underground plant storage repository is the most straightforward — the tap root. Carrots and beets, parsnips and turnips store energy this way.

With well-stocked grocery stores close at hand, and with lots of local possibilities for hunting and fishing, it’s hard to realize how important these plant resources have been in the past, and how important they are to people in many areas in the world today. A good harvest of roots could be the difference between starvation and survival when drought or wet harvests cut stores of staples like grain. It was the failure of a root crop harvest — potatoes — that propelled my own family to make the long trip to the United States and sent millions of other Irish to countries around the world.

Humanity has built systems to mimic the behavior of plants. We use silos and haylofts and freezer systems to stockpile the resources the plants have created from the sun. And we consume animals that eat plants. But so far we haven’t managed to match plants’ ability to take sunlight, air and soil and turn them into nourishment.

Winter is the perfect time to appreciate the miracles plants create underground. Tubers, roots and rhizomes are all tasty treats that make holiday meals special on tables around the nation.