Bird's-Nest Life Cycle

Day 40: Bird's-Nest fungi such as these specimens of Nidula niveotomentosa grow on rotting wood and propagate by means of spores contained in tiny lentil-like structures known as peridioles. Each "nest" is only about the size of a pencil eraser. The "eggs" of this species measure 0.5-1.0 mm and are protected by a gelatinous substance. When this fungus first emerges, the "nest" is covered by a dome which bursts as it matures, revealing the peridioles in the gel. They are then washed from their "nests" as the cups fill with rain. It is not uncommon to find lines of bird's-nests following cracks in old wood or colonies confined to low areas where the peridioles have come to rest. In this photo, you can see one unopened bird's-nest, one in which the peridioles are still suspended in the gel, two which are fully open, and several faded, grey ones from last year. Note also the peridioles on the rims of the cups and one (far right) resting on bare wood.

Nesting Nidula

Day 59: One day I returned a little late to the office after a lunchtime walk and was explaining to Kevin that I had been sidetracked by a specimen of Hemitomes congestum while searching for Drosera rotundifolia, blathering on about the uniqueness of the find and the proliferation of mycoheterotrophic species I had been observing through the months of spring, only to have him say, "Crow, I have no idea what you're talking about." It pulled me up short and made me see that while I was throwing around botanical names and terms as casually as if I had been talking about Fred and George, most people are a bit uncomfortable with scientific jargon. I realize now that it might be easier on my readers if I provided a glossary, so let me give you one to accompany this photo of one of my favourite fungi, Nidula niveotomentosa, aka "Bird's-Nest Fungus."

Very often, the Latin name of a species will tell you something about its characteristics. In this case, "-tomentosa" refers to the presence of a tomentum, a velvety or woolly texture found on the surface of a plant. The view through the microscope at the top left shows this attribute...a fuzzy-wuzzy nest for the "eggs" which give this family of fungi its common name. The "eggs" (shown in the nest in the center 'scope view) are called peridioles. These contain spores. The bottom 'scope view shows the peridioles liberated from the "cup," appropriately called a peridium.

On the right, you can see the Bird's-Nests in situ alongside a flourishing colony of Peltigera membranacea, a member of the family of Pelt lichens. The translucent structures which appear like stalactites on the underside of the "leaf" are rhizines, a root-like structure which attaches the lichen to its substrate of rock, wood or soil. If you think fungus-jive is hard to wrap your tongue around, lichen terminology is another breed of cat. We'll get to that in future posts.