The ghost pipe (Monotropa uniflora) unfurls leafless, almost translucent blooms from even the deepest woodland shadows, often where little else grows. Despite its luminous appearance, the ghost pipe does not utilize sunlight for energy and thus lacks the photosynthesizing chlorophyll that imparts to most plants their lush pigmentation. Instead, it has evolved to siphon all its sustenance from fungi in the soil, in a parasitic relationship called mycoheterotrophy. Its fungal hosts are hardly the worse, as they, in turn, draw nutrients from the roots of trees and other forest plants with which they have symbiotic relationships. On a macro level, these relationships are thought to benefit the forest by triggering the vast underground network of interdependent roots and fungi to transport nutrients where they are needed most.
An entire ghost pipe is typically pearly white, although it may be flushed pink or flecked with black. It is a perennial that sprouts in late spring through early autumn from a flattened clump of entwined, fleshy roots. When first emerging from the soil, its pallid nubs can have the somewhat ghoulish appearance of clenched, dead fingers, lending it the common name “corpse plant.” The plant’s leaves have been reduced to small scales along its stems, which can appear singly or in dense clumps up to 10 inches/25 cm in height. The stem is actually nothing more than a scape, or, flower stalk, as a mycoheterotroph needs no other traditional above-ground plant parts. Each is unbranched and tipped with a single, nodding bloom, forming the crook from which it derives its most common common name, “ghost pipe.” The bell-shaped flower typically consists of five petals, which can be difficult to discern from the sepals1Sepals are modified leaves that enclose a flower bud before it opens and are usually green. and nearly identical leaf scales immediately below it, and five stamens2A stamen is the male reproductive structure of a flower, consisting of an anther in which pollen is produced and usually a slender filament that attaches it to the flower. An individual flower typically has many stamens. that surround a large, flat-topped stigma3A stigma is the organ at the tip of a flower’s female reproductive structure that receives pollen. It is typically connected to the ovary by a style. These three parts together comprise the pistil.. Bumblebees are a known pollinator and somewhat surprising sight in the forest depths this bloom inhabits, a testament to their industry in foraging. After pollination, the stem quickly turns black and straightens, topped by a pointed seed capsule. In this wand-like form, the stem dries and persists into the following year, offering a clue as to the whereabouts of this perennial even when not in bloom.
The ghost pipe can be distinguished from a similar cousin that shares much of its range, the pinesap (M. hypopitys syn. Hypopitys monotropa), by bearing only a single bloom per stem and by its cool white color; the pinesap produces up to thirty flowers along a stem that ranges in warmer shades from pale yellow to nearly red.
The ghost pipe has a vast but irregular distribution across North America, northern South America, and Asia. In Western Washington, look for it at relatively low elevation in deeply shaded gaps on the forest floor in mature conifer or mostly conifer woodland.
Typical Pacific Northwest ghost pipe habitat.
Note the clump of ghost pipes circled in the lower left corner:
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