Coral-roots

 

These are not Manitoba’s most beautiful orchids. But they are among the most interesting.

Manitoba has 37 different species of orchids. They vary greatly from the small and mundane to the large and glorious.  Perhaps none though are stranger than those within the genus Corallorhiza(Coral-roots). We have only 3 of the genus in Manitoba. The name is derived from the Greek word korallionwhich means “coral” and rhizawhich means root.  This refers to the fact that these orchids spend most of their life underground away from the light. They live among the roots of trees and other plants in the forest. The ones in Manitoba rarely live in wetlands, though one comes pretty close.

Coral-roots are mycoheterotrophs meaning that they are not autotrophs, or primary producers, but rather heterotrophs, or secondary producers who cannot produce their own food like the green plants, but rather derive energy from consuming plant and animal tissue. Specifically, they derive their nutrition from nearby mycorrhizal fungiunder the ground who in turn get the nutrition from nearby roots of trees. Their underground life-style does not allow them to produce their own food from sunlight like green plants. Instead they take advantage of a beneficial mutualistic relationship with the neighbouring trees and the mycorrhizal fungi in the ground between them and on them. Since the orchids host the same mycorrhizal fungus that are found in the roots of the adjacent trees the coral-roots are able to use the fungi as a conduit to share the sugars produced by the trees. Trees have green leaves so they are able to produce food, unlike the coral-roots that are unable to produce food because they lack the green chlorophyll.

This is a colony of spotted-coral orchids.

The spotted coral-roots are my favourite. Notice how they  entirely lack green. That is why they are unable to produce food.

Notice how the size of these are reflected by the size of the mosquitos. They are about the same size

The striped coral-root orchids are very distinctive with their prominent dark red stripes.

 

These are coral-roots but they have some green and thus are able to produce some food and are likely not entirely dependent on the associated mycorrhizal fungus under the ground for nutrition.

All I can say for sure is that orchids are fascinating.

Leave a Reply