An online resource based on the award-winning nature guide

Non-flowering plants

Fairy Rings

Occasionally, if you’re lucky, you may come upon a circle of mushrooms in the woods or in a lawn.  To some, these are Fairy Rings, where the fairies dance.  To those more scientifically minded, they are the fruiting bodies of an underground fungus (mycelium) that is growing outward in all directions from an initial spot (in the center of the ring), feeding on nutrients in the soil.  As it grows, the mycelieum secretes enzymes into the ground ahead of it. These chemicals break down the organic matter, releasing nutrients so that the mycelium will have food when it reaches this area. When conditions are right for spore production, the active mycelium produces a circle of mushrooms just behind its outer edge.  Growth of the mycelium continues, accompanied by the formation of wider and wider circles of fruiting bodies every year.

There are roughly 60 species of fungi that produce Fairy Rings.  As a rule they form these in evenly composed soil, such as lawns and less frequently in woods.  It’s possible to recognize Fairy Ring evens when they haven’t sent up mushrooms, as they form rings of grass up to 15 feet in diameter that have a distinctly different color or texture than the grass inside or outside of the ring. (A Fairy Ring in France measured 2,000 feet in diameter and was estimated to be 700 years old.)  (Photos by Julie George)

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Green Stain Fungus Fruiting

Sac fungi, or ascomycetes, are a group of fungi most of which possess sacs, or asci, in which spores are produced. The relatively common blue-green cup fungi, Chlorociboria aeruginascens and its close relative, Chlorociboria aeruginosa, are in this group and are referred to as Green Stain Fungi (as well as Green Elfcup or Green Wood Cup). Most of the time you do not see the actual fruiting bodies of these fungi.  More often you come across the brilliantly blue-green stained wood (often rotting logs of poplar, aspen, ash and oak) for which these fungi are responsible. Woodworkers call this wood “green rot” or “green stain.” 14th and 15th century Italian Renaissance woodworkers used Chlorociboria-infected wood to provide the green colors in their intricate wood inlays. The blue-green discoloration is caused by the production of the pigment xylindein, which may make wood less appealing to termites and has been studied for its cancer-fighting properties.

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Lady Fern Spores Maturing

Ferns are non-flowering plants which reproduce by spores, not seeds, and have a vascular system that transports fluids (unlike mosses, algae and liverworts).  Spores are typically located inside a capsule, or sporangium.  In many species of ferns, clusters of sporangia, called sori, are borne on the underside or margins of their fronds.  Often an indusium, or protective flap of tissue, covers each sorus, protecting the developing sporangia.  If you like to be able to give a fern a name, you will find that the shapes and arrangement of sori are a valuable identification tool.

Northern Lady Fern, Athyrium filix-femina, is a fairly common fern found in moist woods, swamps, thickets and fields.  It appears quite lacy and often grows in a somewhat circular cluster.  There are two distinguishing characteristics which are particularly helpful in recognizing Lady Fern.  One is its eyebrow-shaped sori.  If you look on the underside of a spore-bearing frond you will find that each sori is slighted curved, or arched, like an eyebrow.  The other diagnostic feature is the scattered thin, dark brown scales that are found on the stipe – the section of the fern’s stem between the ground and where the leafy frond begins.

This time of year, when the spores of many fern species are maturing, is a good time to learn the different ferns in the Northeast.  There are many excellent field guides to ferns.  One that you can easily tuck into your pocket is Lynne Levine’s Identifying Ferns the Easy Way.

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Giant Puffballs Maturing

10-17-18 giant puffball IMG_4353Puffballs are aptly named.  When their spores mature and the fruiting body splits open, rain drops, an animal passing by, or the wind cause puffs of spores to burst into the air,  dispersing them far and wide.  While puffballs vary tremendously in size, most would fit in your hand.  Exceptions include Giant Puffballs (Calvatia gigantea), one of which was collected in 1877 in New York state and measured 5 ½ inches by 4 ½ inches by 6 ¾  feet. The greatest recorded weight for a Giant Puffball is 44 pounds.

The production of spores takes place on basidia – club-like structures inside the fruiting body. The number of spores that these fungi produce is impressive. Mycologist Henry Buller estimated that a Giant Puffball measuring 16” x 11” x 8” (a fairly typical size) would contain more than 7 trillion spores.  (If you want to grow your own Giant Puffball so you can count the spores yourself, you can even purchase seeding spores online!)

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Stinkhorns Maturing

10-5-18 dog stinkhorn IMG_9973There are a group of fungi known as stinkhorns — aptly named, as their foul odor can be detected even by the human nose. All stinkhorns first appear as an “egg” which can be up to two inches high. When the eggs rupture, the appearance of the different species of fungi in this family (Phallaceae) can differ dramatically, but many have a phallic-like shape. At maturity, all stinkhorns produce an olive-green to olive-brown slimy substance that has a putrid smell (to humans), but is very appealing to many insects.  This slime is loaded with the fungi’s spores. Insects landing on a stinkhorn get their feet covered with the spore-laden slime while they are busy ingesting it.  Once the insects depart, the spores are dispersed far and wide.

Stinkhorns appear suddenly, and their growth can almost be observed, as they go from the egg stage to maturity with impressive speed. While these fungi are not poisonous, it is doubtful that having smelled them, anyone would desire to eat them.  (Photo:  Dog Stinkhorn aka Devil’s Dipstick, Mutinus caninus)

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Clubmoss Spores Maturing

11-3-17 bristly clubmoss 049A7253

Creeping along the forest floor are small (6” high), evergreen perennial plants that resemble mosses or miniature conifers. Their leaves are usually narrow, shiny and pointed and frequently of similar size. These fern allies (not true ferns) are referred to as clubmosses.   What look like individual plants often are upright stems that come off of one horizontal stem that grows along or under the ground.

Clubmosses evolved some 410 million years ago as one of the earliest groups of vascular plants (plants with special tissues, xylem and phloem, to conduct water and food, respectively). Roughly 300 million years ago, tree forms of both clubmosses and horsetails along with ferns dominated the great coal swamps of the Carboniferous geological period. Fossils reveal that tree forms of clubmosses once reached heights of 100 feet.

Pictured is Bristly Clubmoss (Spinulum annotinum, formerly Lycopodium annotinum). Like all ferns and fern allies, it reproduces with spores, not seeds, and thus has no flowers. The spores are borne on the single cone, or strobilus you see at the tips of the upright stems, and they are maturing now. A slight tap at this time of year will produce a voluminous cloud of yellow spores.

Leathery Grape Fern Fruiting

10-4-17 leathery grape fern2 049A5890

There is a group of evolutionarily ancient ferns referred to as “Grape Ferns.” Although they are true ferns, they are only distantly related to the ferns growing today. They derive their common name from the resemblance of their (spore-producing) sporangia to a bunch of tiny grapes. Grape Ferns have two blades. One is sterile and does the photosynthesizing; the other is fertile and bears the grape-like sporangia.

Different species of Grape Fern mature at different times during the summer. Leathery Grape Fern (B. multifidum; Sceptridium multifidum) is the largest of the Grape Ferns. Its triangular, sterile blade is very leathery and fleshy. If the fern is growing in full sun, the stalk of the sterile blade is usually quite short, and the branching, fertile blade rises above it. The spores on the fertile blade mature in late summer or early fall.