HEBERLING LAB

Not yet blooming here, but it likely is in the Mediterranean.
 
This specimen of lesser celandine (Ficaria verna formerly known as Ranunculus ficaria, in the buttercup family, Ranunculaceae) was collected in January 1911 by Mary F. Spencer in Corsica.  A part of France, Corsica is an island in the Mediterranean.  This specimen was collected in its native range, which extends from Europe to west Asia.
 
Lesser celandine is quite remarkable, one of the earliest blooming spring wildflowers. It isn’t blooming in the Pittsburgh region yet, but can be as early as March.  It was introduced to North America and is actively spreading throughout forest understories in Western PA and beyond, especially along streams and floodplains.
 
Lesser celandine is a problematic invasive species. And only likely to become more of a problem as it actively spreads across the landscape.  It is unique among invasive species, perhaps the only with a “spring ephemeral” ecological strategy.  Spring ephemerals produce leaves and flowers very early in the spring and dies back before the overstory trees produce leaves.  It forms dense mats along the forest floor, crowding out our native spring wildflowers.
 
It was introduced intentionally as a garden plant, producing glossy, yellow flowers which can be quite beautiful.  But it should not be planted, as it negatively impacts our forests and can easily spread outside gardens into natural areas.
 
Keep an eye out for this species in Pennsylvania!  I have been noticing it more each year. 
 
Find this lesser celandine species here:  https://midatlanticherbaria.org/portal/collections/individual/index.php?occid=12087827
 

Lesser celandine (Ficaria verna​) invasion in Fox Chapel, Pennsylvania.  The species can form dense mats on the forest floor, emerging in early spring in a spectacular display of flowers.  But it is very invasive, crowding out native species.  As a spring ephemeral, the species takes advantage of the high light levels in the spring and completes its aboveground life cycle before being shaded out by the trees overhead.

Did you know that one of the earliest Presidents of the United States lived in southwestern PA?  The American soldier and politician Arthur St. Clair, who lived in the Ligonier Valley near Latrobe, Pennsylvania, was President two years before George Washington was! Well, sort of.  The US Constitution wasn’t drafted until the 1787, over ten years after Independence Day 1776.  Before that, under the Articles of Confederation, there was a Confederation Congress.  Arthur St. Clair was elected President of the Continental Congress in 1787. 
 
These patriotic specimens of American Bugbane (Actaea podocarpa, formerly Cimicifuga americana) were collected on July 9, 1999 in the Loyalhanna Gorge (Rt. 30 aka the Lincoln Highway runs through it between Greensburg and Ligonier, PA), near where Arthur St. Clair owned property and lived the later years of his life (now known as Saint Clair Hollow).  In the buttercup family (Ranunculaceae), American bugbane, also called mountain bugbane, is a forest understory herb similar in appearance to the more common black cohosh (Actaea racemosa).  The species is currently listed as threatened in Pennsylvania.
 
Arthur St. Clair was born in Scotland in 1737 and fought with British troops in the American colonies during the French and Indian War.  After the war, he settled in Ligonier Valley and was the largest landowner in Westmoreland County at the time.  He was later a American colonel in the Revolutionary War.  After America gained its independence, he was elected a delegate to the new Confederation Congress (governing body under the Articles of Confederation that pre-dates the Constitution).  He served a one-year term as President of the Continental Congress in 1787, during which time the Northwest Territory was created.  He later became governor of the Northwest Territory (large area which are now Midwest states).  After retiring, he returned to live out his days in the Loyalhanna Gorge (between present day Ligonier and Greensburg, not far from Idlewild Park).  He died in poverty in 1818.
 
Many towns in Pennsylvania and the Midwest are named after Arthur St. Clair, including Upper St. Clair near Pittsburgh.
 
A lot of history in Western Pennsylvania!
 
Happy 4th of July! 

​Keep an eye out for these bright yellow flowers blooming now along creeks across southwestern Pennsylvania. This specimen of lesser celandine (Ficaria verna, formerly known as Ranunculus ficaria) was collected in Edgeworth, Pennsylvania along Little Sewickley Creek by Myrta Macdonald and Jane Konrad in April 18, 1986. Native to Europe, lesser celandine was likely first introduced to the United States into gardens for ornamental purposes.  It is a spring ephemeral, meaning it blooms early in the spring and goes dormant by summer. Lesser celandine is among the earliest species to bloom in the spring, with bright yellow flowers.  In the past several decades, this species has become more and more common in southwestern Pennsylvania.  It grows in open woods, especially in moist soils along streams.  It forms dense mats that carpet the ground, capable of choking out native plants. 

Specimen below: Lesser celandine specimen from its native range in England, collected on April 13, 1826.

​Invasive lesser celandine is easily confused with the native wetland plant, marsh marigold (Caltha palustris).  Marsh marigold is found in somewhat similar habitats and has a similar appearance as lesser celandine.  However, there are several major differences.  Most notable, marsh marigold does not form dense, continuous mats along the ground, but instead plants are distinctly separate (although can be large and robust).  Also, lesser celandine has tuberous roots, while marsh marigold does not.  Compared to lesser celandine, marsh marigold is found in wetter habitats, has fewer flower petals (5-9 in marsh marigold vs. >8 in lesser celandine), and has larger leaves that are more rounded.

Specimen below: Be careful not to confuse lesser celandine (Ficaria verna) with the Pennsylvania native wetland species, marsh marigold (Caltha palustris).  This marsh marigold specimen was collected on April 28, 1887 in Westmoreland county, PA by P.E. Pierron.  The herbarium of St. Vincent College (Latrobe, Pennsylvania) became a part of the Carnegie Museum herbarium in 1991. 

We humans have moved plant species around the world at unprecedented scales. Human-mediated species introductions are a signature of the Anthropocene. Some of these non-native plant introductions were intentional, in the case of ornamental or food plants.  And some of these plant introductions were accidental, often in the case of “weeds” associated with human disturbance, cities, and/or agriculture. When introduced plants can survive and sustain a population without human intervention, we call these species “naturalized.”  When naturalized species are capable of reproducing at high rates and spreading across the landscape, far from the point of introduction, we call these species “invasive.”  This process from introduction to naturalization to invasion can occur quickly, but in many cases, there is a lag such that species introduction to full blown invasion can take decades to realize.
 
Herbarium specimens play a critical role in understanding species invasions, serving as a valuable archive of introduced plants.  When were species first introduced? Were they first introduced accidentally or were they intentionally planted in gardens? Where were species first introduced? Were they introduced multiple times at multiple locations? How have these introduced species spread in the decades to centuries since introduction? Have their morphology or genetic makeup changed since introduction?  Which introduced species become naturalized, which become invasive, and which species fail to establish altogether? These are just a few of the many questions that can be answered using herbarium specimens. 

Collected on July 15, 2005, this specimen was found in by Ralph Thompson and Derick Poindexter.  This forest understory plant (Actaea pachypoda) is known as white baneberry or “doll’s eyes.” “Baneberry” comes from the fact that the berries are poisonous.  Most plants in this genus contain toxins that have sedative effects on human cardiac muscle, which can lead to cardiac arrest and death. In July through October, it is easy to see where the name “doll’s eyes” comes from— the berries are bright white with a black pupil like spot that looks like that of an old-fashioned porcelain doll.