Tuesday, September 20, 2011

Rattlesnake Plantain Seed Heads

An abundance of Orchid flowers should translate into an abundance of Orchid seeds. Downy Rattlesnake Plantain, Goodyera pubescens, is the earliest common orchid to bloom at Blue Jay Barrens, so it makes sense that it would be the first to develop seed pods. It looks as though seeds from this species are going to be quite abundant this year.

There are many ways of assessing the health of a plant population. Counting total plants or just counting blooming individuals are two common methods that I frequently use. Counts such as these are fairly easy to accomplish and allow you to track changes in population size over time. If I were to choose a single indicator that I felt most represented a thriving plant population, it would be the ability of the plants to produce an abundance of viable seed. For that reason, I’m always encouraged by the sight of plants developing masses of seeds.

Rattlesnake Plantain is one of those plants that produces a tiny seed that is distributed by the wind. The long flower stalk elevates the seed head so the seeds are more likely to be caught and carried by the wind. Wind action also causes the stalk to flip back and forth in a way that propels the seeds from their capsule, so there is more seed released during windy times. It would really be something if all those seeds could produce plants, but the likelihood is slim of any one seed landing in a suitable area for germination.

The height and thickness of the flower stalk seems out of balance with the leaf base. It may take the plant several years to store enough energy to send up that stalk and produce seeds.

I still think the leaves are the most attractive part of the Rattlesnake Plantain. The leaf cluster present the year before flowering is particularly impressive. The leaves often decline and the leaf cluster may die completely after flowering, but there are usually offshoot plants that develop to take its place. The leaves and flower stalk develop from a rhizome that often branches at the site of the leaf clusters, so even if one leaf cluster dies, the plant continues to live. What sometimes appears to be a group of many plants is often just a collection of leaf clusters arising from rhizomes that originally came from a single seed derived plant. The rhizome develops roots beneath the leaf clusters so that it can appear that the plants are independent of each other. This causes people to think that they are seeing a collection of individual plants instead of a clonal colony that developed from a single source.

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