- Crucibulum laeve (Huds.) Kambly – Common Bird’s-nest Fungus
- Taxonomic history
- Identification guide
- Culinary Notes
- Reference Sources
- Bird’s nest fungi isn’t harmful to plants
Crucibulum laeve (Huds.) Kambly – Common Bird’s-nest Fungus
Phylum: Basidiomycota – Class: Agaricomycetes (Gasteromycetes) – Order: Agaricales – Family: Agaricaceae
Distribution – Taxonomic History – Etymology – Culinary Notes – Identification – Reference Sources
Crucibulum laeve is one of several species of bird’s-nest fungi and is among the most common. That’s not to say that any of the bird’s-nest fungi are easy to find, as they are so tiny and easily overlooked. This remarkable fungus grows on rotting wood (commonly small twigs) and dead stems of other vegetation. Initially a yellow-brown, tapering cup-shaped fruitbody with a yellowish woolly membrane covering the top, once mature the embrane fall away revealing egg-like peridioles that contain the spores of the fungus.
The ‘eggs’ are attached to the base of the nest by fine threads that break when raindrops knock the eggs from the nest. By this unusual means the spores are dispersed.
Probably fairly common and widespread throughout Britain and Ireland but rarely reported because they are so small and inconspicuous and because their most common habitat is dark, damp woodland, Common Bird’s Nest fungi are found also throughout other temperate parts of the world including mainland Europe and Asia. This species is known to occur in many parts of North America.
This gasteromycete fungus was described in 1778 by the British mycologist William Hudson (1730 – 1793), who gave it the binomial scientific name Peziza laevis.
It was American mycologist P E Kambly who in 1936 transferred this speces to the genus Crucibulum, whereupon it acquired its currently accepted scientific name Crucibulum laeve.
The generic name Crucibulum means in the form of a crucible, while the specific epithet laeve means smooth – a reference to the smooth inner surfaces of the ‘nests’.
Stemless cup-shaped fruitbodies, each ‘nest’ containing typical five to eight whitish ‘eggs’ each typically 1.5mm in diameter. A ‘nest’ is typically 5 to 10mm across and up to 10mm tall. In its immature state each nest or peridium is covered by a yellow-orange membrane, as shown on the left. At maturity the cover ruptures around the rim, and then wind and rain can contact the eggs (peridioles) and disperse them.
Often these fungi occur in such densely-packed groups that nests become distorted by the pressure from neighbouring fruitbodies.
Ellipsoidal, smooth, 8-11 x 4-6µm; inamyloid.
Habitat & Ecological role
Saprobic, mainly found on fallen dead twigs, old rotting timber (including discarded plywood, as seen on the left) and decaying vegetation. Distribution seems to be very patchy.
July to October in Britain and Ireland.
Several similar species occur throughout Europe. Cyathus striatus (with ribbed nest walls) and Cyathus olla (often on manured soil) are also found occasionally in the British Isles, mainland Europe and further afield.
These fungi are reported to be inedible. My investigations to date have revealed no recipes for cooking these kinds of eggs, and the Common Bird’s Nest is not an ingredient of any kind of bird’s nest soup… as far as I know!
Fascinated by Fungi, Pat O’Reilly, 2011.
Dictionary of the Fungi; Paul M. Kirk, Paul F. Cannon, David W. Minter and J. A. Stalpers; CABI, 2008
Taxonomic history and synonym information on these pages is drawn from many sources but in particular from the British Mycological Society’s GB Checklist of Fungi and (for basidiomycetes) on Kew’s Checklist of the British & Irish Basidiomycota.
This page includes pictures kindly contributed by Simon Harding an Hilary Rose.
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Bird’s nest fungi isn’t harmful to plants
Question: What are these strange things growing on top of the soil of one of the houseplants I set outside for the summer? They look like little bird nests. Is this a disease that will hurt my plants?
Answer: What you are seeing is a type of bird’s nest fungus. There are several species, and you can think of them as little mushrooms with their caps turned upside down. Instead of the spore-bearing gills found on the underside of many mushroom caps, bird’s nest fungi have disk-like structures that look like eggs in a little nest or smooth stones in a cup. When raindrops splash into the cups, they spread the spores. This gives some of them the name “splash cups.”
Bird’s nest fungi live off dead organic matter such as the mulch underneath your shrubs and around your flowers or the organic matter in potting soil. They are harmless to plants. They are not edible. If you don’t want them, scrape them off the surface of the soil.
Q: Can we grow wishbone flower in Georgia?
A: Absolutely. It is an easy-to-grow annual that is good for planting in containers or in the ground. Wishbone flower will take full sun but will bloom and thrive in partial shade. It likes moist but well-drained soil.
The plant gets its name from how its connected stamens look like a wishbone. It is more often sold today under the name “torenia.” Colors range from violet and purple to pink, white and even yellow.
Wishbone flower blooms all summer, and is usually sold at garden centers in spring and early summer. It is easy to grow from seed. It is also listed as a houseplant that can be grown in winter in sunny windows.
Q: When is the next auction of rehabilitated horses in Georgia?
A: The next auction will be Saturday, Sept. 23, at the Lee Arrendale Equine Center, 645 Gilstrap Road, Alto, GA 30510. For more information, contact the Georgia Department of Agriculture’s Equine Health Office at 404-656-3713.
Q: The leaves on my gold dust plant (aucuba) look like they are scorched black. Is it fire blight?
A: The damage might look like fire blight, but it is sun scorch from the plant getting too much intense summer sunlight. Prune out the dead leaves and move the shrub or plant a more sun-tolerant shrub.
Consumer Qs is a weekly question-and-answer column by Arty Schronce at the Georgia Department of Agriculture. Please share your thoughts, questions and suggestions with him via email at [email protected] or visit the Georgia Department of Agriculture’s website at www.agr.georgia.gov.
Fruiting bodies of fluted birds nest fungus, Cyathus striatus.
There are many fungi in several genera called bird’s nest fungi because of the resemblance of their fruiting bodies to a tiny nest filled with eggs. One of the most common in Wisconsin is Cyathus striatus, the fluted bird’s nest fungus. This species is widespread throughout temperate regions of the world, developing on dead wood in open forests, typically growing individually or in clusters on small twigs and fallen branches or other wood debris. Because it also grows readily in bark or wood mulch, it is frequently found in landscaped yards and gardens. Other species grow on plant remains or cow or horse dung.
A large cluster of fluted birds nest fungi growing on bark mulch.
C. striatus, and others, are most commonly seen in the autumn when damp conditions promote their development, but they can be seen anytime conditions are appropriate. Even though each individual is small and inconspicuous, this species often grows in huge clusters, making them more noticeable – although they blend in so well with their background that it is very easy to overlook them.
The fruiting body is a cup-shaped nest filled with eggs.
All of the bird’s nest fungi look like miniature nests (generally only ¼ inch in diameter) filled with four or five tiny eggs. The cup-shaped “nest”, called a peridium, may be brown, gray or white, and smooth or textured inside and out. The “eggs” are actually disc-shaped bodies called peridioles that contain basidiospores.
Cyathus striatus has a rough, shaggy exterior.
The vase-shaped body acts as a splash cup.
Bird’s nest fungus in different stages of development growing in wood mulch.
C. striatus has rough, shaggy or hairy exterior and smooth but grooved inner cup walls, features that easily distinguished it from other similar bird’s nest fungi. This species varies somewhat in size and in color from a bright orange-brown to dark grey or dull brown, darkening with age. The peridioles vary in color from gray white through various shades of brown to almost black. The vase or cone shape of the nest part of the fruiting body allows for a splash-cup mechanism of dispersal of the spores when the “eggs” (peridioles) are hit by raindrops. The downward force of the drop hitting the interior of the cup ejects the peridioles into the air. The peridioles can be propelled up to 3 feet away, and stick to whatever they land on. After a while the periodioles split open to release the fungal spores.Small animals can also eat the spore-filled peridioles to disperse the spores after they pass through the digestive tract. In most situations the peridioles are unlikely to be noticed, but if lots of the “eggs” stick to the siding on a house or exterior of a vehicle they can be a nuisance as they are difficult to remove. You can try to manage the number of fruiting bodies by keeping conditions drier (good luck when it rains a lot) and raking mulched areas to disturb their growth. Growing a living ground cover will help, as well.
If the basidiospores released from the peridioles land on suitable wood or bark, generally in damp and shady spots, they germinate and produce new mycelium that infiltrates the wood or bark. Eventually when conditions are appropriate, that mycelium grows into new fruiting bodies. The immature nests are covered by a thin membrane called an epiphragm. Eventually this lid degrades once the peridioles are ripe, opening up the cup to expose the “eggs”, so that rain can splash them out to continue the cycle. The cups are very tough and persistent, so remain in the environment well after the “eggs” are splashed away.
A young, closed fruiting body (L); one with the epiphragm starting to degrade (C); and one fully open exposing the peridioles (R).
– Susan Mahr, University of Wisconsin – Madison
What is growing on my mulch? This is a common question UConn Extension is asked at the UConn Home and Garden Education Center and in our county Master Gardener offices. People are perplexed when they find a yellow foamy mass that looks like the neighbor’s dog vomited in their flower garden. Or when their nice white-sided house is suddenly speckled with tiny black spots that will not come off no matter which cleaning agent they use or how hard they scrub. Or homeowners notice the sudden eruption of very interestingly shaped mushrooms popping up through the mulch.
No, these are not the work of garden fairies and a miniature landscape construction crew, but the result of fungus hard at work. All of the above named structures are the fruiting bodies of naturally occurring fungus. These are decomposers doing their job in life, rotting natural organic material, and breaking it down into its basic chemical form. This is composting.
The mulch most commonly used in our yards is dead wood and/or bark material chopped or shredded into a uniform size. We use it to keep the weeds from sprouting, to maintain a constant temperature of the soil and to retain moisture in soil. Mulch looks neat and showcases the plants. These are all great functions, but this mulch will not last forever. As soon as it is placed in the garden beds, the natural invaders attack it. Bacteria and fungi that live in all soil recognize this wonderful new food source for them! You have fed the decomposers and they are going to thank you by getting right to work.
The bacteria decomposers are microscopic and not visible to the naked eye. Most fungus is also microscopic until it grows to the point of producing a fruiting structure, sometimes called a mushroom. This fruiting structure contains the spores or seeds of the fungus, much like the fruiting structure of an apple tree is an apple, which holds its seeds that can grow a tree. Weather conditions have to be ideal liking for the fungus to reproduce. Fungus likes it moist. Temperature preferences vary with the type of fungus involved.
The body of a fungus starts as a single spore landing via wind currents or expelled from the fruiting structure. That spore grows into a strand called a hyphae; groups of these hyphae all grow together forming what’s called a mycelia mat. Sometimes this is visible as a white coating or mass. When the fungus matures and the weather is right, a fruiting structure appears above ground. This is the part we notice. Most all of the decomposers are harmless to our live plants. They feed on the dead material. All can appear spring through fall, especially after a period of rainy weather. No mushrooms growing in your mulch, in the lawn or in the wild should be eaten. It is best to consider all uncultivated mushrooms poisonous.
Changing the environment will lessen all the fungal growth on any type of mulch. Keep the mulch dry. Do not aim sprinkles at mulch, but direct water to plant roots. When you do water, apply one to two inches of water per week, all at one time. Daily watering for short periods does not penetrate deeply in the soil, but remains in the mulch and top few inches of soil. Two inches of mulch is enough to retain soil moisture and block light from reaching weed seeds. Top dress last year’s mulch with a light ½ inch of new mulch to dress up the beds. In rainy times, stir up the mulch with a rake to break up any colonies of fungus. This will also fluff up and dry out the mulch making it less hospitable for fungal growth. There are no fungicides available to control fungal growth on mulches.
The most common encountered fungi are chronicled here.
Dog Vomit Fungus is a slime mold. It has a blob-like shape and bright yellow color that will fade to a sickly orange brown as it matures. The end result is a powdery brown pile that will erupt in a wisp of spore being released when it’s disturbed. This cloud of fine dust spreads mold spores to a new spot. It has no preference as to the type of mulch. Slime molds feed on the bacteria that are feeding on the mulch, not actually eating the mulch directly. Control is not necessary unless you are unhappy where it is appearing. Just shovel it off to the compost pile if you don’t like it.
Artillery Fungus is a nuisance and can cause damage to homes, cars and anything within reach of its spore spewing range. The artillery fungi’s fruiting structure is a tiny, 1/10 of an inch, cream or orange-brown cup with a black egg. When the fruiting structure is ripe, it explodes shooting its black, sticky spores twenty feet in all directions. The cups are attracted to light colored surfaces, due to their light reflecting ability. Of course, the sticky black spores show up nicely against the white background. The spores will not grow on vinyl or painted surfaces. They need dead organic material to feed upon and colonize. The sticky coating of the spores is incredibly strong and durable making it very difficult to remove. So far, no commercial or homemade cleaner has proven effective to remove the spots from cars or houses. If scraped off, they leave a mark or stain. Artillery fungus does prefer to grow on mulch made of the interior of the tree rather than mulch made from the bark. Soft woods such as pine, is also less hospitable to artillery fungus.
Bird’s Nest Fungus looks like tiny grey to brown nests holding tiny eggs. The nest portion can be up to ¼ inch wide. The egg looking part is a mass of spores in the nest released and splashed out of the holding cup when raindrops land on them. They do not shoot out like the artillery fungus. These spores sometimes stick to surfaces but are easily removed, not leaving a stain. It’s less common than artillery fungus, and doesn’t appear to have favorite mulch.
The common name of Stinkhorn doesn’t quite describe how bad these smell. You will smell a colony of stinkhorns before you ever marvel at their sight. The strong scent is used to lure animals and insects that normally feed on decomposing flesh to touch them. The slime substance coating the fruiting body holds the fungal spores, attaching to the animal or insect, which will move onto another area eventually spreading the spore far and wide. Stinkhorns can occur anywhere there is composted material as a food source.
Written by Carol Quish for UConn Extension. For more information please visit our Home and Garden Center at www.ladybug.uconn.edu or call 877-486-6271 in Connecticut or 860-486-6271.
Common bird’s nest fungi growing on a mulch bed in Alliance in early August. The little oval “seeds” will be splashed out of the cup or “nest” and will release spores wherever they land. (CM 8/6/2014)
Most every fall I find these curious little fungi growing in the mulch beds around my home and elsewhere around the area. They look like tiny cups filled with a few sesame seeds or, as their name implies, tiny little bird’s nests. They show little superficial resemblance to the mushrooms or bracket fungi that we usually associate with fungi. They are all mushrooms and bird’s nest fungi alike, members of the club fungus phylum, called Basidiomycetes by scientists.
There are several different species of bird’s nest fungi in northeastern Ohio but they all belong to the same family, Nidulariaceae. The scientific name is derived from the Latin word “nidus”, meaning nest. Most members of this family are tropical or subtropical with only a few reaching the latitude of northern Ohio. As is the case for many fungi, the bird’s nest fungi do best in warm moist conditions. The bird’s nest fungi are rather small. They typically reach a height of from only 1/3 to 2/3 of an inch above their substrate and have a diameter a little more than one-quarter of an inch.
The tiny birds’ nests are really only the reproductive portion of the fungus. The fungus spends most of its life as a series of nearly invisible threads that snake among strands of decaying wood and other dead organic matter. The fungal threads, called hyphae, secrete enzymes from their bodies. These enzymes have the ability to digest wood and turn the cellulose into soluble sugars and the lignin into phenolic compounds. What is left after the initial decay process is residual organic matter that may persist for eons in the soil and which make the soil darker and generally more fertile.
Though the structures in the cups, which are called peridia, look a great deal like seeds, they are not seeds. No fungus produces seeds. Even some of the early botanists in the 1600’s thought the structures were seeds. But we now know that the egg-like structures, called peridoles, produce spores. The cups are shaped in such a way that if a rain drop falls into the cup, the peridoles (eggs) are splashed out, often travelling for several feet from their “nest.” The peridoles then stick to some nearby substance, often a twig or even a leaf.
After an uncertain amount of time the peridoles will open and the spores will spread in the wind. Many spores will be released but only a very few will be able to grow into a mature fungus. If a spore germinates and grows successfully, it will spend months or even years growing slowly, digesting wood outside of its body and producing more fungal biomass. Eventual when it has stored sufficient energy and when the temperature and moisture conditions are right the hyphae will organize themselves into the reproductive structures that we recognize as the bird’s nest. Apparently bark mulch creates ideal conditions for the Nidulariaceae because there are often hundreds of the reproductive structures growing on the same area. They are often found on mulch that is a year or older, which is not surprising since it takes them that long to have grown enough to produce reproductive structures.
Fall is a great time to explore the world of fungi. On a short walk through the woods you may be able to spot a dozen different shapes and colors if you go slowly and look closely. Unfortunately for humans many of the fungi are toxic and every year people die from liver or kidney failure after eating what they thought were safe mushrooms. Bird nest fungi are considered inedible, but not toxic Please do not try to taste any fungi unless you are totally sure of what you are eating.
For more information:
University of Minnesota, Extension, webpage on bird’s nest fungi