Plants Without Partners
Many Missouri families keep alive a tale of Grandad's walking stick. The story has many variations, but they basically all revolve around Grandad jamming his walking stick into the ground. The stick later sprouts into a living tree. Even Henry David Thoreau wrote of such an occurrence.
It sounds fanciful, but the tale may be factual. Lots of Missouri plants propagate by means of cloning.
Cloning has been in the news lately, but it's not really new. Cloning occurs naturally all of the time. It's a means of reproduction for many plants.
Essentially, cloning is reproduction without sex. Unlike sexually produced offspring, which have a blending of genes from both parents, Cloned offspring have the genes of only one parent, In fact, a clone is a genetic duplicate of its sole parent.
Nearly all Missouri plants that clone also reproduce sexually through flowers and seeds. Cloning, sometimes called vegetative reproduction, merely diversifies their reproductive capabilities.
If you've ever noticed a grove of sumac in the shape of a mound, you've seen the results of cloning. The oldest plants are in the center and are taller than those around them. The younger, shorter plants sprout from underground runners around the perimeter. Eventually, the runners wither away, leaving a completely independent sumac that is genetically identical to the sumac beside it.
Sassafras and gray dogwood are two common Missouri plants that also reproduce through this type of cloning. That is why you seldom see these plants growing alone. They're nearly always in small groves of genetically identical plants.
Many plants use underground runners to clone themselves. Several grasses use this method to spread through the soil. So do strawberries. A ring of May apples on a moist forest floor is a sign that cloning has been underway (and underfoot). May apple colonies can perpetuate this way for half a century if left undisturbed.
Blackberries, which have a three-year life cycle, have a different method of cloning. In the first year, the cane establishes itself. During its second year, the cane flowers and bears fruit, reproducing sexually. In the third year, the cane droops to the ground, giving blackberry brambles their characteristic, "bales-of-barbed-wire," look. When the drooping cane touches the ground, it can set roots for a new plant. Eventually, the original cane will dry up and break away, leaving a completely independent clone of the original plant. From there, the three-year cycle begins anew.
Black raspberries perform a similar cloning act, but