An online resource based on the award-winning nature guide

Non-flowering plants

Horsetails & Scouring Rushes

5-20-16  equisetum044Horsetails and Scouring Rushes are in a primitive genus (Equisetum) of non-flowering plants.  Most of their stems are hollow and have distinct nodes, or swollen areas, where branches are sometimes attached.  Both stems and branches have vertical ridges and grooves.  Silica, embedded in the ridge tissue, led to the stems being used to scour pans as well as an abrasive for burnishing brass and finishing violins.

Equisetum leaves are barely recognizable as leaves – these pointed structures fuse into small sheaths surrounding each node.  A spore-bearing cone forms at the tip of the fertile stems.  If you look closely you will see that hexagonal plates (modified leaves) cover the surface of the cone.  Underneath these plates are the sporangia, in which spores are produced.  Upon maturation of the cone, the sporangia expand, split open and release their spores. (photo: Variegated Scouring Rush,Equisetum variegatum )

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Mycorrhizal Relationships

12-15-15 white pine 047The woods are filled with all kinds of plants – herbaceous and woody, flowering and non-flowering. Each plant appears to be independent of all others, but this is an illusion. In fact, most of the plants in a forest are physically connected to one another. How and why this is so is a little known fact.

Fungal threads called hyphae (the subterranean body of a fungus that we don’t usually see) run throughout the soil. Each one is ten times finer than a plant’s root hair. While some are digesting dead organic matter, others are forming a relationship with photosynthetic plants. This mutually beneficial relationship between fungi and plants is referred to as mycorrhizal.

The very fine fungal threads are capable of penetrating plant cells, allowing the fungus to receive sugars that the photosynthetic plant has manufactured. At the same time, the fungus provides the plant with minerals (especially phosphates) it has garnered from the soil. Nearly all plants have mycorrhizal fungi wrapped in or around their roots, and many of these plants cannot live without their fungal partners. The real work of a plant’s roots may well be to serve as the connector to this network of fungal hyphae that exists in the soil. (photo: Eastern White Pine,Pinus strobus)

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Maidenhair Spleenwort Greening Up the Woods

ebony spleenwort 083Five species of spleenworts (genus Asplenium) can be found in New England. Most of these small, native, evergreen ferns are found growing among rocks or on cliff faces. The Greeks believed that a species of spleenwort was useful for treating diseases of the spleen. The genus name Asplenium is derived from the Greek word for spleen (splen).

Maidenhair Spleenwort (Asplenium trichomanes) is divided into two subspecies, one that grows in crevices of acidic rocks and one that grows on more basic (alkaline) rocks. It grows in tufts and has long (three to six inches), delicate fronds made up of short, round leaflets paired from the central dark reddish-brown stem (stipe and rachis). If in doubt as to whether or not a spleenwort is Maidenhair, examine the stipe and rachis with a hand lens; if there is a narrow wing running the length of the fern frond, it is A. trichomanes.

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Jelly Fungus Fruiting

11-15-15  jelly fungus IMG_1009The term “jelly fungus” is an informal one applied to species of fungi that have a gelatin-like consistency. The reason for this texture is that the structural filaments, or hyphae, of these fungi have walls that are not thin and rigid as they are in most other species, but instead shrink and expand in response to moisture. The hyphae are expanded and gelatinous when moist, but during dry periods they collapse and become rather hard and resistant to bending. These tissues are able to exist in a dry state for many months and, when exposed to moisture, quickly expand to full size. They may be among the earliest fungi seen in the spring because they have remained dry and inconspicuous all winter, only to revive with the first melting snow or during winter thaws. Jelly fungi come in several colors. Some of the orange and yellow forms found growing on deciduous trees, especially oaks and beech, are called “witches’ butter.”

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Common Polypody Spores Dispersing

10-27-15 rock polypody 057Common polypody (Polypodium virginianum), also called Rock Cap Fern, is a perennial plant found most often growing on rock surfaces usually in moist, shady woods. Being a fern, Common Polypody reproduces by spores. Structures that produce and contain spores (sporangia) are found on the undersides of the fertile frond leaflets. The sporangia form round clusters called sori. The sori of Common Polypody are orange-brown when mature and lack the protective covering (indusium) that some other fern species have. At this time of year, the mature spores are being dispersed by the wind.

The ability of Common Polypody to tolerate extreme desiccation (the leaves roll up when moisture isn’t as available, and resume their normal state when moist conditions return) means it is well adapted to the extreme moisture fluctuations of rock surfaces. Its evergreen fronds are consumed in the winter by Ruffed Grouse, Wild Turkey, and White-tailed Deer.

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Green Stain Fungus Fruiting

10-15-15 blue green cup fungus 038Sac fungi, or ascomycetes, are a division 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. (They differ microscopically by the size of their spores.) Most of the time you do not see the actual fruiting bodies of these fungi (see photo). More often you come across the brilliantly blue-green stained wood (these fungi grow on the rotting logs or barkless wood of poplar, aspen, ash and especially 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 can inhibit plant germination and has been tested as an algaecide. Xylindein may make wood less appealing to termites, and has been studied for its cancer-fighting properties.

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Northern Tooth Fungus

9-22 northern tooth fungus 159Northern Tooth Fungus, Climacodon septentrionale, is an unusual combination of both a shelf (also called bracket) fungus as well as a toothed fungus. Typically a shelf fungus produces spores inside pores located on its underside. Northern Tooth Fungus, however, produces spores on pendant, spine- or tooth-like projections on its underside (see insert). This fungus usually has several tiers of “shelves” that grow in tight, thick layers, and change from white to light tan as they age.

Northern Tooth Fungus is a parasite of living trees, especially Sugar Maples, and it causes the central heartwood of the living tree to rot. The only sign that a maple has this fungal parasite is the appearance of these shelf-like fruiting bodies in late summer or fall. Often trees with this fungus become weak and are blown over by the wind. As with most shelf fungi, it is considered to be inedible. (Thanks to Jeannie Killam for photo op.)

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