An Aromatic Parasite

What smells like honey and parasitizes fungi? Why, Monotropa hypopitys of course! Its specific epithet gives you an idea of where you may stumble across one of these strange beauties. Hypo means under and pitys means pines. It is no wonder then that the common name of this species is "pinesap."

I love parasitic plants and to find this species was a real excitement. I smelled it before I saw it. The yellowish coloration of this specimen represents the norm, however, individuals with a more reddish hue are not unheard of. Pinesap has a distribution spanning the forests of the northern hemisphere. It is the most widely distributed member of the genus. Despite this fact, stumbling across a population is a relatively rare occurrence.

Pinesap falls under the category of mycoheterotroph. It parasitizes fungi, specifically those in the genus Tricholoma. As such, it is an indirect parasite of trees, taking nutrients that the fungi obtained from the trees they associate with. The relationship between pinesap and its associate fungi are rather specific. The structures they form are so unique that researchers have created a new term just to describe it - 'monotropoid’.

For most of its life, pinesap lives underground as a collection of highly specialized roots. Come early summer, individuals with enough stored energy will throw up what looks like a stem covered in flowers. In actuality, pinesap does not produce anything that could be called a true stem. Instead, the structure we see is actually an inflorescence called a raceme.

As mentioned above, the flowers have a scent that reminds me of spicy honey. Bees are the main visitors of the flowers, though most researchers feel that the plant mainly self pollinates. It has been observed that yellow individuals tend to flower earlier in the summer while red individuals tend to flower closer to fall. Whether this is any indication that these are separate subspecies remains to be seen. Recent genetic analysis suggests that pinesap may very well deserve its on genus, Hypopitys monotropa. More work needs to be done to figure out if it is deserved.

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