Orchids

The orchid is a flower of superlatives. Often thought of as one of the most beautiful flowers, orchids are also the largest family of flowering plants or angiosperms in the world. There are at least 25,000 species of orchids—10 percent of all flowering plant species. Orchids also produce the smallest seed of any flowering plant.

Orchids are believed to be the most evolved of the flowering plants. Orchids have evolved such specific needs for habitat, pollination and germination that a whole host of needs must be perfectly met before the plant can propagate. But its patience pays off. Orchids live in more types of habitat than perhaps any other plant family.

While most people think of orchids as tropical plants, orchids can be found in every climatic zone from arctic to tropic and on every continent except Antarctica. Orchids can be found from very high elevations to lowland swamps. Orchids further diversify the habitats they are found in by not limiting themselves to terrestrial growth. Epiphytic orchids grow in trees.

In Maryland we have 52 different species of orchids, most are rare or difficult to find, but some can be found in our area with out much trouble.

Orchids are monocots, which are different from other flowering plants because they have only a single leaf, known as a cotyledon, when the plant first emerges from the seed. Like many monocots, orchid flowers have three sepals (the little usually green "leaves" around the flower) and three petals. Typically, two of the petals are similar and one is distinctive, forming the lip common to most orchid species.

Many of the orchids in our area have that distinctive orchid flower. Perhaps the most common orchid in our area is the pink lady’s slipper (Cypripedium acaule). The pink lady’s slipper has a very distinctive pink lip petal about 2.5 inches long with thin greenish brown upper petals. The pink lady’s slipper is a large native orchid growing up to a height of fifteen inches. It also has two large (8 inches), dark green basal leaves. To make it even more striking, the pink lady slipper often grows with hundreds of plants in a small area. They are found in drier pine oak forests, at high and low elevations, in our area and flower between April and July.

Populations of pink lady’s slippers can be found as close by as Greenbelt Park and likely Sligo Creek Park. When encountering these beautiful flowers in the wild do not be tempted to try to bring it home and plant it in the garden. Orchids, because of their highly evolved relationship with soil fungi, will not transplant. These flowers should not be removed from their habitat.

Another species of orchid that can be found in drier pine-oak forests in the area is the rattlesnake plantain (Goodyera pubescens), which is not a plantain at all. Unlike the pink lady slipper’s dominant single flower, the rattlesnake plantain has a cluster of many small white rounded flowers similar to a snapdragon or gladiola. The quarter-inch flowers bloom from May to September, but the rattlesnake plantain’s distinctive leaves make it identifiable when not blooming. Bring along a field guide when out looking for orchids. While there are some specialized field guides for mid-Atlantic orchids, Audubon’s guide to wildflowers will have most of the common orchid species.

Further into the mountains, one can start to find showy lady’s slippers (Cypripedium reginae) with a beautiful white and pink orchid shaped flower. A single plant can have up to 3 flowers and will sometimes reach a height of three feet. It also has large green leaves, approximately ten inches, which help to show off the flowers. The showy lady’s slipper is found in moist woods, especially around limestone sites.

The large twayblade (Liparis liliifolia) can be found in rich or sandy woods and clearings along stream banks. The flower of the twayblade is much thinner than the typical orchid flower, but also quite beautiful. The lip petal is about a half-inch long and brown with purple veins. This orchid can be found on hikes through the Pautuxent Wildlife Refuge.

There are many other spectacular orchids in our area waiting for a patient hiker to admire. The large yellow lady slipper or the swamp pink would be quite a find. Or maybe you would be as lucky as Professor Doug Gill and his students who found a three birds orchid, a stunning white orchid previously thought extinct in Maryland. It is not an easy one to find. The plant can remain dormant for years and then when the flower blooms it will last only a day. The sight of a wild three bird orchid is something very few people have ever seen.

April is the month when orchids start to bloom in our area. Take a hike in Greenbelt Park or the Pautuxent Wildlife Refuge and spend the day looking for orchids. The reward is spectacular when you find one, but the consolation prize—a beautiful walk in the woods with the songbirds singing and the rest of the forest coming alive—isn’t too bad either.

Doug Gill, Norm Bourg, and Gary Dodge from the University of Maryland were of great help in writing this article.