Showing posts with label Spiranthes. Show all posts
Showing posts with label Spiranthes. Show all posts

15 September 2014

Orchids Are Weeds

Okay, so maybe saying that orchids are weeds is a bit of a dramatic exaggeration.  However, while mowing the trails on our St. Joseph County, Indiana property yesterday, I had to slam on the brakes inches from mowing the fourth orchid species that we've documented on our property, October Lady's Tresses (Spiranthes ovalis var. erostellata). If you're a follower of this blog, you may know that the previous three orchids we'd found on our property were Ragged Fringed Orchid (Platanthera lacera), Purple Twayblade (Liparis liliifolia), and Green Twayblade (Liparis loeselii).  After finding the third of those, I asked readers of this blog (tongue in cheek) which orchid species we would find next.  Keith Board has to win some kind of prize for predicting that we would find this species.  My find today is even more interesting because I saw this species growing on the St. Joseph and Elkhart county line on Friday last week and came home to look for it on our property in a young successional wooded area.  I struck out.  I guess I was looking in the wrong place and instead needed to be sitting on a riding mower to find it.
 

Sure, a weed is often defined as a plant out of place.  In that sense, I don't necessarily consider orchids weeds.  However, the more I see and learn, the more I think that many of our orchid species require disturbance to grow, reproduce, and continue to be evident above ground, and without that disturbance, they cease to exist (at least until the disturbance returns) (see the dialog in the comments of this post for a discussion on this topic).  In this case, the orchid I found is growing right at the edge of the trail that I mow regularly, in old-field, with mostly non-native species and weedy native species such as Tall Fescue (Schedonorus arundinaceus), Riverbank Grape (Vitis riparia), and Poison Ivy (Toxicodendron radicans ssp. negundo). 


As seen in the photograph below, the flowers of October Lady's Tresses (also known as Oval Ladies'-tresses) are usually in three spiraling ranks.  The flowers (and specifically the lip) are smaller than many of the other members of the genus Spiranthes, with the lip reaching only approximately 5.5 mm; the other two species that have flowers that minute in the lower Great Lakes region have either a yellow or green spot on the upper surface of the lip.  The lip on October Lady's Tresses is quite recurved and is usually inrolled, giving it a narrow appearance. Another good field character used to help identify October Lady's Tresses is seen in the photograph above... notice that the leaves are present and conspicuous when the plant is in flower. 


Whereas many of our Spiranthes grow in full sun habitats, October Lady's Tresses is more shade-tolerant and does best in openings in woods, along trails, and in young successional woods.  It also is found in thickets and in old-fields.  When forests mature and less light can reach the forest floor, this species tends to be less prevalent, an indication that it requires disturbance. You can see the habitat where I found the plant on our property in the photograph below (it is just about in the middle of the photo).  Not an area that anyone would consider "high quality" by any means.


The range of October Lady's Tresses includes the eastern United States and the province of Ontario.  However, it is not known from more than a large handful of counties in any of the states in which it occurs, and its county distribution is fairly even over its range.  That said, this species is increasing its range and distribution, likely in part due to the increased level of disturbance to our natural areas.  So... is it just a weed?  Certainly a unique and welcomed one on our property!

22 September 2010

A Fen-tastic Saturday Morning, Part II

As promised in my previous post, this entry will focus on some of the plants that Nate Simons and I saw while touring some of the fen preserves in northeastern Indiana last weekend.


One of the characteristic (and often dominant) plant species found in northeastern Indiana fens is Shrubby Cinquefoil (Dasiphora fruticosa ssp. floribunda, previously known as Potentilla fruticosa), pictured above. This low-growing shrub in the Rose Family (Rosaceae) has a North American range that includes much of the northern and western half of the continent. Nate referred to this plant as the "McDonald's Plant," as it is often found in the landscaping of fast food chains. A calciphile, Shrubby Cinquefoil is often used in wetland rapid assessments as an indicator of a fen community.


Another species found in nearly every Indiana fen in which I've ever set foot is the inconspicuous but intricate Grass of Parnassus (Parnassia glauca), shown above. With a distribution restricted to northeastern North America, this unique member of the Saxifrage Family (Saxifragaceae) or Parnassia Family (Parnassiaceae) has flowering stalks up to two feet tall topped by a single flowers; foliage consists of a single egg-shaped leaf clasping the lower stem, as well as a basal rosette of small, stalked, egg-shaped leaves.


I am not normally one to get overexcited about our charismatic macroflora, but the plant pictured above definitely gets a free pass in my book. This is Lesser Fringed Gentian (Gentianopsis procera, which is now apparently treated by some as Gentianopsis virgata ssp. virgata). Lesser Fringed Gentian or the similar Greater Fringed Gentian (G. crinita) are found in nearly all northern Indiana fens, but the two members of the Gentian Family (Gentianaceae) are very rarely found growing on the same site. Few plants can match the beauty of Lesser Fringed Gentian.


Quite showy in its own right but often ignored because of its similarity to sister species, Crowned Beggarticks (Bidens coronata, also known as B. trichosperma, shown above) is a plant of wet areas including marshes and fens of eastern North America. This member of the Sunflower Family (Asteraceae) can look most similar to Tickseed Sunflower (B. polylepis) and Bearded Beggarticks (B. aristosa), as all of these have leaves with 3-7 (or more) linear to lanceolate lobes and large, showy, yellow ray flowers. Crowned Beggarticks often has leaf lobes that are more linear with fewer teeth, and its fruit are narrower and longer in relation to their width than those of Tickseed Sunflower and Bearded Beggarticks.


Kalm's Lobelia (Lobelia kalmii, above) is a common and often abundant plant of Indiana fens, but with flowers that measure up to only 1/2 inch long, it often goes unnoticed (especially when not in flower). Found throughout the northern half of North America, this member of the Bellflower Family (Campanulaceae) or Lobelia Family (Lobeliaceae) grows in bogs, wet meadows, and along streams in addition to in fens and other calcareous situations.


If you are ever in a fen or a bog and you see the shrub pictured above, your best bet is to keep your distance. This is Poison Sumac (Toxicodendron vernix), a species found regularly in northern Indiana fens and bogs. The common name and genus (meaning "poison tree") both refer to the rash that results from making contact with the urushiol present in all parts of the plant. Found primarily in the eastern third of North America, this member of the Cashew Family (Anacardiaceae) possesses stunning fall foliage in colors ranging from yellow to orange to red to purple; the drooping white berry-like fruit add to the aesthetic value of what I think is one of the most attractive of our native shrubs.


As mentioned in my previous post, fens in northeastern Indiana are often dominated by grasses and sedges. Tussock Sedge (Carex stricta) and prairie grasses such as Big Bluestem (Andropogon gerardii) and Indian Grass (Sorghastrum nutans) are the most conspicuous and well-known of these graminoids, but one of the matrix species found in nearly every fen is the grass shown above, Marsh Wild Timothy (Muhlenbergia glomerata). Marsh Wild Timothy is found in the northern half of North America in a range of plant communities including bogs, fens, hot springs, marshes, and wet meadows.


It seems that anytime I see Greater Fringed Gentian (Gentianopsis crinita) or Lesser Fringed Gentian (G. procera), I also see Nodding Lady's Tresses (Spiranthes cernua) nearby, and these northeastern Indiana fens were no exception. Nodding Lady's Tresses (above) is in the Orchid Family (Orchidaceae), and is found throughout much of the eastern half of North America in open plant communities ranging in wetness from wet to dry. In northern Indiana, this is one of our most common orchids.


Standing taller than many of its companion species in northeastern Indiana fens, Swamp Thistle (Cirsium muticum, above) is a more attractive and better behaved version of the non-native thistles that threaten many of our natural areas. With a similar geographical range to the previous species, this member of the Sunflower Family (Asteraceae) grows in bogs, fens, wet prairies, marshes, and open wet woods.


During our outing, we saw two species of Juncus, both of which possess seeds with (relatively) long white tail-like appendages. The more common species that we encountered was Smallhead Rush (Juncus brachycephalus, not pictured), but we also saw Canadian Rush (Juncus canadensis), shown above. Some people would look at the photograph above and think that it was a grass or a sedge, but like other members of the Rush Family (Juncaceae) and unlike grasses (Poaceae) and sedges (Cyperaceae), Canadian Rush has flowers that are radially symmetric with three sepals and three petals, looking much like a tiny version of a classic flower. In Canadian Rush, the flowers are clustered into round or nearly round heads. This species is found throughout the eastern half of North America, as well as in a few locations in the Pacific Northwest, in a variety of wet areas including those with high acidity, alkalinity, or salinity.

One reason that fens are so interesting to me is that you can go back to the same location at various times throughout the year and see a different suite of species blooming during each trip. In later summer and early fall, goldenrods (Solidago) provide much of the color. The following three species of goldenrod were found in all of the fens we visited.


Ohio Goldenrod (Solidago ohioensis, or Oligoneuron ohioense for those who choose to split Solidago) is one of the most common fen species of goldenrod. Restricted to states and provinces surrounding the Great Lakes, this member of the Sunflower Family (Asteraceae) grows mostly in calcareous wet soils. This and the next species both possess flat-topped inflorescences.


A goldenrod similar in appearance to Ohio Goldenrod and found growing with it in northern Indiana fens is Riddell's Goldenrod (Solidago riddellii, or Oligoneuron riddellii), shown above. Riddell's Goldenrod has a slightly greater geographical distribution, extending west across the Mississippi River. Riddell's Goldenrod has leaves that are folded in half lengthwise and often pointed at the tip, whereas the leaves of Ohio Goldenrod are flat and often blunt at the tip.


A third goldenrod species that we saw in all three northeastern Indiana fens is Bog Goldenrod (Solidago uliginosa). Unlike the previous two species, the inflorescence of Bog Goldenrod is not flat-topped. This species (treated in the broad sense) is found throughout much of the eastern half of North America in bogs, fens, marshes, and wet woods.

I hope that this brief account of northeastern Indiana fens in the late summer/early fall gives you a good idea of why fens are so special and amongst my favorite places. My next post, in about a week, will conclude my recap of Nasby Fen, Sawmill Fen, and Lime Lake Fen, and will touch on some of the butterflies we noticed while botanizing.