I was confused!! Several weeks ago I found and photographed a patch of flowers along the North Umpqua Trail (Oregon) just above the Boundary Waters. I thought the flowers were pyrola. Yet pyrola have leaves and none of these plants had leaves. Were they a heterotroph that contain no chlorophyll and thus cannot photosynthesize their own food? Or were they pyrola without leaves?
Plants with green leaves are autotrophs and make their own food. Plants without chlorophyll (heterotrophs) are either1) parasites and obtain their organic carbon directly from a host green plant or are 2) mycotrophic and obtain their organic carbon from the host green plant by utilizing an intermediary mycorrhizal fungus attached to the host plant’s roots. There are also “mixotrophs”, plants which obtain some of their food from photosynthesis and some through mycorrhizal fungi.
It turns out that Pyrola picta (white-veined wintergreen) has a broad range of morphological characteristics that seem to reflect the ratio of organic carbon obtained from autotrophy and heterotrophy, mixotrophs. There is even a leafless form of P. picta that is a true mycotrophic wildflower. Wow!! My unknown flowers! This mycotrophic form has been given a scientific name, Pyrola aphyllia, and is called leafless wintergreen, but is probably not a distinct species at all.
Let’s confuse things more: Leafless wintergreen has flowers that occur as two different colors, greenish white like white-veined wintergreen or pink like the color of pink wintergreen (Pyrola asarifolia), or even an intermediate of the two. So is leafless wintergreen a mycotrophic form of white-veined and/or pink wintergreen? Botanists are sequencing the DNA of these different Pyrola species and perhaps some day the puzzle will be solved. For now, I will simply refer to these leafless pyrola plants as leafless wintergreen or P. aphyllia, be happy that I solved the mystery and not worry about whether it is a true species.
Pyrola wildflowers are called wintergreens because they are extremely cold hardy. In the middle of winter the plants can be found in good condition under the snow. These are not the same “wintergreen” or teaberry plants from which oil of wintergreen can be extracted. Those belong to the Gaultheria genus. More confusion! But I find it all very fascinating.
Tomorrow the post specifically about leafless wintergreen should be more straightforward. I hope!