Orchid Seed Longevity

by Dee Strickler

My wife Claire and I live on a 2-acre plot in the Flathead Valley that was at one time a rather dense lodgepole pine forest, with a few Douglas-firs and western larch trees thrown in. The area was logged, perhaps 50-100 years ago as indicated by the presence of a few large rotting larch stumps. An old logging road crosses our property, which I partly mow to give access to my vegetable garden at the back. I connect two garden hoses to water the vegetables and the hose connection rests on the old logging road. We let about two thirds of our lot go wild, except for removing many beetle-killed lodgepoles.

A few years ago a power company truck drove onto the old road to repair the power line along the back of our property and, of course, ran over the hose, causing a small leak at the connection. Being a procrastinator, I let it go for a few years until another power company truck caused a big leak.

The year after the leak began, up popped a beautiful little white orchid! (ladies’ tresses, Spiranthes romanzoffiana). The next year a couple more appeared and the following year another half dozen showed up. Ladies’ tresses usually require moist or perpetually wet earth in order to thrive. After I fixed the big leak, the ground dried up and so did my little white orchids.

So, how long had those tiny orchid seeds lain in the normally dry, sandy soil waiting patiently for a couple of wet, rainy years to come along so they could germinate, grow, bloom and produce more tiny seeds? More than twenty years to my certain knowledge. Could they have been there many millennia dating back to the final receding of Lake Missoula? Could they have been there many hundreds of years since the last rainy weather cycle, whenever that was? Perhaps the most logical scenario is that they were deposited there in mud from the tires of logging trucks or horse-drawn wagons about 100 years ago or so. A damp drainage channel near by could easily have been the original source of the seed or the logging machinery could have carried them for many miles. I am a little saddened, because I will never know the answers to these intriguing questions.

We also have a couple of Trillium ovatum that showed up 20 years after we moved here, just off the edge of our lawn, where they enjoy the occasional overwatering of the lawn.

Now I am sorely tempted to begin watering that old logging road regularly. There’s no telling how many dormant wildflower seeds would germinate and produce beautiful blooms. It probably wouldn’t be the silliest thing I’ve ever done, but what would the power company employees think? Surely they wouldn’t understand...a service truck stuck in deep mud on an old, unused road in flat terrain in the middle of a drought! I might get sued or have to go without power, but it might be worth it.