Showcase on the Sedges (Cyperaceae)

Sedges.  The mere mention of this monocotyledonous group can make even the most enthusiastic of plant lovers furrow their brow.  That comes as no surprise as the complexity and excruciatingly similar characteristics of the family is well known and subsequently shunned by some.  They typically aren't for botanical greenhorns but can quickly become a fevered obsession to some.  Don't fear though!  This post is geared towards the artistic and aesthetic aspect of the family and its respective genera/species with some basic information.  I don't want to overdue it and drown my readers in a deep treatment full of botanical jargon and drool-inducing paragraphs; even if it sounds like fun to me!  I'm one of the aforementioned folks with the hots for this family.

Carex sartwellii among the Virginia irises in a west-central Ohio fen meadow

The Cyperaceae family is arguably the largest (grasses in the Poaceae could have more, I've never counted and compared) in Ohio with 250+ species in 15-16 different genera.  Sedges come in all shapes and sizes.  Some are so minute you need a hand lens to accurately inspect the plant, while others can be taller than you and/or occur in large, sprawling colonies.  Despite many species appearing very similar, they all display a unique and sometimes fascinating arrangement, look, and/or feel to them.  Many species are downright beautiful and architectural works of wonder as you'll soon see.  Fair warning: most sedges don't have common names and only go by their Latin botanical names.  If all else fails, just glance at the photos and admire these all-too-frequently overlooked plants!

Carex communis flowering in the early spring

The largest and most diverse of the Cyperaceae's genera are the true sedges from the Carex genus.  Ohio is home to over 160 different species and account for a nice chunk of our botanical biodiversity.  The photograph above shows the delicate pollen-laden staminate (male) flowers and the clear, thread-like pistillate (female) flowers on the flowering culms of Carex communis in early spring.

Display of associate sedge species from a calcareous fen meadow

All Carex have three-ranked (triangular) leaves/culms and their achenes (seeds) each individually encased in a papery sack called a perigynium (perigynia plural).  the perigynia make up the spikelet (fruit) and are hands down the most attention-grabbing part of a sedge.  Above is a lineup of some Carex species typically found in west-central Ohio's calcareous fen meadows.  From left to right: C. stricta, C. buxbaumii, C. viridula, C. sterilis, C. flava, C. leptalea, C. suberecta, and C. hystericina.

Next are a handful of different Carex species I find visually appealing and worth an extra look at.  Admittedly, they also happen to be some of the species I've managed to remember to photograph.  With so many wildflowers and trees around, it's sometimes hard to focus your lens on such small botanical bounties.

Carex grayi

Carex lurida

From R to L: Carex frankii, C. crus-corvi, C. lupulina, C. lupuliformis, C. grayi, C. comosa, and C. crinita

Carex hyalinolepis

Carex utriculata

Carex buxbaumii

Of all of Ohio's indigenous sedges, this one may be my favorite.  Buxbaum's sedge (C. buxbaumii) has perigynia of a spectacularly distinct green color that is contrasted brilliantly by its dark pistillate scales.  This uncommon species is most frequently found in Ohio's calcareous fen meadows but also occurs in marshes, wet flatwoods, and other wet, open habitats.

Carex squarrosa

Carex aurea

An interesting note about Carex aurea (pictured above right), is the fact its achenes are edible and have somewhat of a nutty taste to them.  I gave it a try after snapping the picture above with my iPhone and wasn't displeased at their taste.  Not too bad!

Comparison between C. comosa on L and C. pseduocyperus on R

An example of two similar species can be seen above with C. comosa on the left and the very rare, state-endangered C. pseudocyperus on the right.  Careful examination and measurement of the perigynia and their beaks is essential in this particular case!

Sea of Carex intumescens growing in the deep shade of a wet, acidic flatwoods in southwestern Ohio.

Now it's time to move away from the diverse Carex genus and explore a number of other genera in the Cyperaceae family and some of their representative species.

Browning clump of woolgrass (Scirpus cyperinus) growing alongside a pond.

The Scirpus (bulrushes) genus is represented by eight species in Ohio, with the photographed woolgrass (Scirpus cyperinus) being one of the most frequent species.  Bulrushes are vital food sources for waterfowl and other aquatic critters.  The bulrushes tend to be the largest/tallest of the Cyperaceae members as well.

Eleocharis obtusa 

Eleocharis (spike rushes) is a diverse and notoriously difficult genus that requires careful study of their tiny achenes and other inconspicuous characteristics to identify them down to species level.  Spike rushes have small terminal spikelets and culms with extremely reduced leaves (blades often absent).  There are 16 taxa native to Ohio with many being rather rare, or at least overlooked.

Rhynchospora capillacea

Rhynchospora capitellata

Rhynchospora (beak rushes) are named for the tiny "beak" or tubercle that caps each achene in this genus.  Their spikelets occur terminally and are arranged in glomerules, or compacted clusters.  Here in Ohio we only have a handful of species (including the two photographed above) but further to the south/east this genus is represented by dozens of species.

Eriophorum viridicarinatum

Eriophorum (cotton grass) is one of the most immediately-recognizable and distinguishable Cyperaceae genera for its woolly perianth bristles that are quick to catch the eye.  Unlike the aforementioned Rhynchospora genus whose range is primarily in the southeast; this genus is predominately found in the boreal north's fens and bogs.  Ohio is home to only three species and all three are quite rare in their limited distribution.

Cladium mariscoides

Cladium (twig rush) is a small genus of only three North American species and only one member in Ohio.  Our sole species, C. mariscoides occurs in calcareous fen meadows, marly mud flats, and marshy shorelines.  A relative of our twig rush, C. mariscus in the south is known as sawgrass for its hard, serrated edges that can easily slice open mammalian skin.

Schoenoplectus purshianus

Schoenoplectus saximontanus

Schoenoplectus (naked-stemmed bulrushes) is a relatively new genus split out from Scirpus and still goes by the common name of bulrush.  This genus has species that can be have either triangular or round stems in cross-section; which can cause for some confusion.  However, its small, clustered spikelets accompanied with an erect, non-leafy proximal bract (looks like a continuation of the stem) can help them stand out.

Scleria triglomerata

Scleria (nutrushes) might be my favorite genus out of all the Cyperaceae.  There are only four species to be found in Ohio but their very artistic achenes definitely set them apart.  The achenes turn bleach white when mature and have a unique pattern and/or combination of characters that help identify them to the species level.  I definitely plan to delve into our state's four taxa in their own dedicated post in the near future.

Dulichium arundinaceum

Dulichium (three-way sedge) is a monotypic genus, meaning only one species (D. arundinaceum) represents the entire genus.  This unique plant does an excellent job of displaying the three-ranked leaves trait when looking straight down from above.  The thin, needle-like structures are this species' achene-bearing spikelets.  It occurs sporadically throughout the state in wet-moist, open soiled situations.

Lipocarpha drummondii

Lipocarpha (dwarf bulrush, halfchaff sedge) is one of the most dainty and unique of the Cyperaceae genera  in Ohio.  Only two species occur in our state and both are extremely rare and only occur in a few places. The plants are small, densely tufted annuals with very thin culms that bear equally small spikelets near the apex. Keep an eye out for this genus in northwest Ohio's flat, sparsely-vegetated sand plains and swales.

Trichophorum alpinus

Trichophorum (club rush) is a weird but charming genus that physically looks very similar to the spike rushes (Eleocharis) with a single, small, and terminal spikelet; however Trichophorum spp. culms have reduced, but noticeable leaf blades.  This particular species, T. alpinum pictured does not occur in Ohio but has the added bonus of perianth bristles reminiscent of the cotton grasses (Eriophorum); which this species is sometimes placed in.  In Ohio, we only have a single species found in upland, dry oak forests called T. planifolium.

the native annual Kyllinga pumila (L) sitting next to the invasive, non-native and rhizomatous K. gracillima

Kyllinga (greenhead-sedge, spike sedge) is last but certainly not least.  This often overlooked and diminutive native sedge is quite charming and handsome in its own right.  Our native species, K. pumila is an annual with a fibrous root system (seen on left above) and can easily be told apart from the newly-invading, non-native Asian species, K. gracillima, which is a perennial with a rhizomatous habitat.

There are a handful of genera I currently do not have photographs of (Bolboscheonus, Bulbostylis, Cyperus, and Fimbristylis) that I hope to add to this post sometime in the future.  If anything, I hope you've discovered that between the diversity and difficulty of this family, there is an awful lot of beauty.  You only have to look a little harder, sometimes with the aid of a hand lens to see it!

A Couple Cool Carex

Geeze, say that post title five times fast!  For those that are not familiar with the Latin lingo of the botanical world, Carex is the genus for the 'true' sedges.  They hail from the family Cyperaceae which contains well over 5,000 species in over 100 genera; with Carex being the largest. What's a sedge you ask?  Well, they look almost identical to their monocotyledonous flowering plant brethren, the grasses (Poaceae) and rushes (Juncaceae) to the untrained eye but with a couple key differences.  Sedges have stems that are triangular in cross-section and have leaves in a spiraling three-ranked pattern.  Three-ranked means there are three planes to the leaves, appearing like this: /_\.  Grasses and rushes are two-ranked so they appear like this: |  | and have stems that are round or occasionally flat.  I've always been told to follow the ol' saying, "Rushes & grasses are round and sedges have edges" and it seems to work pretty well.

With over 160 species of Carex found in Ohio, this quickly ranks as one of the most difficult and frustrating genus' to tackle for any botanist, greenhorn or experienced.  I know my fair share already but I've put a large majority of them off for too long and have decided to make 2011 the year of the sedges and do my best to learn as many as I can.  I can hear a few of you muttering, "good luck" under your breath as you read that and I'm sure I'll need as much as I can get.  So with that being said let's take a look at two really neat species in full bloom right now.

Carex picta female plant

Carex picta male plant

Leading off is Boott's Sedge (Carex picta), which has the very unique and interesting trait of being one of the few diecious sedges.  Diecious means that male (staminate) and female (pistillate) flowers occur on separate plants while monoecious means just the opposite.  If you find these plants as enthralling as I do and wish to seek them out for yourself you're going to have to go next door to  Indiana.  C. picta has a disjunct population in a handful of counties in South-central Indiana and can be found in increasing frequency as your move farther south.

Carex picta staminate flowers

Carex picta pistillate flowers

Taking a closer look at the terminal inflorescence spikelets on this sedge you can see that the male and female plants are relatively easy to tell apart.  The staminate flower spikelet is reddish in color and emits many pollen covered anthers that are honey yellow.  Gently tapping the culm (stalk) will send a tiny shower of yellow pollen 'dust' into the air.  The pistillate flowers on the other hand terminate in a spikelet at the end of the culm as well but differ in color quite noticeably.  The spikelet is dark purple, almost black with tiny, white 'hairs' protruding out of the sides.  These hairs are the female flowers that once pollinated will mature into the tiny seeds called achenes, wrapped up in their papery perigynia (the structure where the achene matures and pistil protrudes).

Staminate flower

Pistillate flower

Above are two macro shots of the staminate and pistillate flowers to show in detail their respective differences.  While many sedges are wetland species and found where moist or saturated soils abound, Carex picta seems to do just fine on drier, well-drained soils.  These plants were found on the upper slopes of a mature Oak/Hickory woods with Greenbrier (Smilax rotundifolia) running wild on the ground, making for a rather uncomfortable and difficult photo session.  Oddly enough, sedges are most commonly identified by taking a look at the mature achenes under magnification, looking for subtle differences while most other vascular plants are identified by flowers or leaves (not to say sedges cannot be I.D.'ed in that manner as well, it just doesn't always work out to your advantage).

Carex plantaginea

Carex plantaginea

The second species I wanted to introduce is the relatively easy to identify and equally cool, Plantain-leaved Sedge (Carex plantaginea).  Named for it's resemblance to the entirely unrelated Plantain genus of Plantago, the wide, ribbon-like leaves spill down from its rosette like a waterfall of vivacious green.  I find this sedge to be very aesthetically pleasing regardless of the time of year.  It it rather uncommon in Ohio, only being found in a handful of counties in the Northeast, a few to the Southeast and a couple in the West-central  section of Ohio.  It prefers shaded, cool, mesic deciduous woodlands with deep, rich soil and really thrives in deep ravines and gorges where cooler temperatures and high humidity persist.  The two best places I've seen this plant grow in profusion is Conkle's Hollow Nature Preserve and Clifton Gorge Nature Preserve.  Both are excellent examples of its aforementioned preference for cool and humid places.  I've also seen it scattered throughout ravines and north-facing hillsides in my favorite haunts in Athens County.

Carex plantaginea

Carex plantaginea

Taking a look at the flowers you can see this sedge follows the much more common rule of being monoecious.  The culms terminate with the staminate flowers and the smaller spikelets of the white 'haired' pistillate flowers patiently wait below for the slightest of breezes to send a cloud of pollen its way.  I really find the flowers of sedges to be more deserving of our attention as I'm sure 99% of people walked right past these plants without even a glance or notice.  While shooting these photo's in Conkle's Hollow I'm sure I had a few people give me looks and questioned my sanity as all they saw was a grown man laying flat on his stomach taking pictures of what appeared to be clumps of grass.  I could try and explain to them just how neat these plants are but I fear my words of excitement and proclamation would fall on deaf ears.  They truly are beautiful and transcending in their own respective ways.  So next time you find yourself out hiking this Spring keep an eye out for any sedges sending up the flowering culms and sit down for a quick meet and greet.  They may not be as large and showy as the surrounding Spring ephemerals but they certainly fill any knack for something contrary to your normal list of Spring plants.