The Curious Beekeeper
Stem Cells, Weeds, and Honey Bees
“Do weeds have stem cells?”
The question coming from my phone was a non sequitur, so unexpected that the only stems I could picture were the sort that support flowers, so I wavered. “Yes. No. What?”
“I’ve been pulling weeds for days,” my husband complained, “and under the soil surface, there’s this white nodule. If I don’t get the whole thing, the weed returns in 20 minutes.”
“Right,” I said, impressed he knew what a stem cell was, and I understood exactly what he was saying. Sometimes those sub-surface nubbins appear dry and unassuming; other times they leak a sticky milk-colored sap, but grow they do. And grow and grow.
The basics of stem cells
The convoluted biology of stem cells and epigenetics encompasses both plants and animals, but whenever the science intersects with humans, it becomes contentious and divisive. So here, I want to explain what nature herself does with this miraculous system of adaptation. As for what humans can or could or should do with stem cells is fodder for a different journal.
At its most basic, a stem cell has no specific duty. It can become specialized, but when it first forms, it’s like a lump of Play-Doh, a blank canvas simply waiting for direction.
Whether found in plants or animals, stem cells have two common properties. First, they can freely reproduce themselves. In other words, a stem cell can make more stem cells, which can make even more, a trick that assures a constant supply of virgin Play-Doh. And second, stem cells can differentiate (or change) into special cells with special properties, depending on the need. In essence, stem cells are biological repair kits, kept ready and waiting for any emergency.1
Depending on where stem cells originate, they may be totipotent, meaning they can become any kind of cell, or pluripotent, meaning they can become any of the cell types within a particular organ.
Stem cells in plants
More so than animals, plants teem with stem cells. Because of them, the fragments and roots you leave in the soil will soon sprout stems, leaves, new roots, or whatever the plant needs to properly deface your lawn, garden, and driveway.
Stem cells are the reason a cut lawn grows back, a pruned bush balloons fat and lush, and a dead-headed dahlia grows another bloom. Stem cells allow you to grow a plant from cuttings, and they allow layering, grafting, and teasing a potato from a seed piece. Nearly all non-seed plant reproduction is possible because of stem cells …
