Mason Heberling

This poinsettia specimen was collected on December 20, 1990 by Sue Thompson from a potted plant in Pittsburgh.  Poinsettia (Euphorbia pulcherrima) are native to Mexico, but now widely cultivated. 
 
Look closely at the colorful “flowers” of poinsettia.  Upon close inspection, you’ll notice that those bright red or white (or otherwise colorful) structures are not flower petals, but specialized leaves called “bracts.”  The actual flowers are yellow and quite tiny.  The brightly colored bracts function to attract pollinators to the flowers.
 
Poinsettias are an excellent example of a “short-day” plant. (Or, more accurately, a “long-night” plant).  That means that as the length of darkness at night increases, a complex process begins that signals flowering and the production of pigments in the bracts. 
 
Poinsettias are woody perennials –  meaning you don’t need to throw them away after the holidays!  However, to flower again for next season, it takes some effort. They must experience days with less than 12 hours of daylight for 8-10 weeks straight.  That means you must provide the plant with 13-16 hours of complete darkness (uninterrupted!) in order for it to flower for December.  This may take some commitment to remember to put it in a dark closet each day, but well worth the effort.  Or just enjoy the green foliage year after as it grows larger.

 
This specimen image is now publicly available online: http://midatlanticherbaria.org/portal/collections/individual/index.php?occid=12144209&clid=0
 

Are you decking your halls with boughs of holly? Probably not holly from 178 years ago!

​This holly specimen (Ilex aquifolium) was collected in 1840 in England.  I think the label says it was collected by “Prof. Sager,” but it is hard to read!
 
How did it end up at the Carnegie Museum herbarium?  This specimen was part of the private herbarium of Jacob Wolle, who was the grandfather of William J. Holland, one of the first directors of the Carnegie Museum (from 1901-1922). The CM herbarium has 2,514 specimens from Wolle’s collection, dating as far back as 1819! 
 
 
Find this specimen online: http://midatlanticherbaria.org/portal/collections/individual/index.php?occid=12131603&clid=0
 
 
Also, find nearly 400 other holly specimens collected in Pennsylvania, just digitized and now online! http://midatlanticherbaria.org/portal/collections/list.php?db=328&hasimages=1&taxa=Ilex&usethes=1&taxontype=2
 

​When in candy cane form, it is easy to forget where the flavor came from.  Peppermint (Mentha x piperita) is actually a hybrid between two other mint species, water mint (Mentha aquatica) and spearmint (Mentha spicata).  It is commonly grown for food or medicinal herb in gardens.  It is also well known to escape garden settings and spread aggressively.  Like other mints, this species is in the plant family Lamiaceae, which includes many strongly scented kitchen herbs.  Members of the mint family are well recognized by their unique flowers and characteristically square stems.
 
This peppermint specimen was collected on August 29, 1965 by Norman R. Farnsworth in an open field at Ranalli’s Drive-In, eight miles north of Etna off Route 8, outside of Pittsburgh, PA.
 
Farnsworth (1930-2011) received his PhD from the University of Pittsburgh, where he researched medicinal plants.  He was an influential professor and researcher in the field of pharmacognosy (study of medicinal drugs derived from plants).  He was a founding member of the American Society of Pharmacognosy.
 
The Carnegie Museum herbarium includes 1,108 specimens collected by Farnsworth.  Each specimen is quickly recognizable, with an envelope attached to each sheet that includes a standard typed description of the results of chemical screenings he did on the specimen.

Hopefully you have some peppermint that is fresher than than this for your recipes this year!

 
‘Tis the season for spices.
 
Nutmeg is well known, but what is it?  Nutmeg (Myristica fragrans) is an evergreen tree native to the Maluku Islands, an archipelago in Indonesia.  In fact, the Maluku Islands were even once known as the “Spice Islands” because nutmeg, mace, and cloves are endemic to the islands (meaning they are native there and nowhere else).  However, the species are now widely cultivated across the world. 


Both nutmeg and mace are made from Myristica fragrans, also known as fragrant or true nutmeg. The spice called nutmeg is made by grinding the seeds of this species, while mace is made from the fleshy seed covering (outgrowth from seed called an aril). 
 
This nutmeg specimen from the Carnegie Museum herbarium was collected in Trinidad on August 17, 1924 by Edward H. Graham.  Graham was an assistant in botany and later assistant curator of botany at the museum (from 1922-1937).
 
This specimen was collected as part of Graham’s research toward his PhD from the University of Pittsburgh.

Specimen image available online:
http://midatlanticherbaria.org/portal/collections/individual/index.php?occid=12088342&clid=0

High resolution specimen image available online here!

Not all plants have leaves.  Beech drops (Epifagus virginiana) is one such example. This specimen was collected on November 16, 1884 growing on the root of a beech tree (Fagus grandifolia) at the back of a cemetery in Allegheny county.  The specimen was collected by John Shafer, who a decade later became the first curator of botany at the Carnegie Museum of Natural History.  Beech drops is a parasitic plant – rather than having leaves to photosynthesize, the species produces root-like structures (called haustorium) that parasitizes roots of beech trees. 

The genus “Epifagus” refers to this parasitism on beech (“epi”= upon; “fagus” = beech).

Beech drops are in the  broomrape family (Orobanchaceae), which is comprised mostly of parisitic plants.

Check out the beautiful, distinctive purple and white flowers in late summer to autumn.

Photo taken September 12, 2018 at Riddle Run, Springdale, Pennsylvania.

Perhaps not the most beautiful specimen in the collection, but check out the prickly stem! Former Carnegie Museum curator Otto Jennings described this species as “an obnoxious weed of farmlands and waste places” (1953).  This leafless specimen of Carolina nightshade (Solanum carolinense) was collected on November 9, 1915 in “Pittsburgh district” by Frank R. Alker. Carolina nightshade (also called horse nettle, wild tomato, and many other names) is in the potato/tomoato family (Solanaceae).  It is commonly found in disturbed and anthropogenic (human-made) environments, such as those in cities. 
 
Horse nettle is native to the Southeastern US, and now widely distributed as a naturalized species across the world. Although native to parts of the US (probably including PA), it is considered a noxious weed in some states.
 
This specimen is available virtually online at http://midatlanticherbaria.org/portal/collections/individual/index.php?occid=12257516&clid=0

Botanical signs of fall are everywhere, to name a few --  colorful leaves, apples, squash, pumpkins, and the many wild and cultivated fall flowers. Among the most popular plant flowers in fall are those in the genus Chrysanthemum (in the sunflower family, Asteraceae), or best known as simply “mums.” They are native to Asia, but many horticultural varieties exist. Mums have been cultivated by humans for at least several thousand years, with evidence in Chinese writings dating back to 15th century BC.
 
This beautiful mum specimen was collected in “Fall” in 1914 by John Jones at Phipps Conservatory, Schenley Park, Pittsburgh.
 
High resolution image available here: http://midatlanticherbaria.org/portal/collections/individual/index.php?occid=11826736&clid=0

​Staghorn sumac (Rhus typhina) collected on October 19, 1929 near Penn Hills (Rosedale), PA by W.R. Van Dersal. This species is in the cashew family (Anacardiaceae), which is includes many painfully irritating species like poison ivy and poison sumac (although both of these species are not closely related, but in different genera).
 
For some reason, staghorn sumac is one of those species that I find iconic in Western PA.  Common along roadsides, farms, and old fields.  Its leaves are often brilliant red in the fall.  The fruit persist on branches through winter.
 
Sumac specimens in the Carnegie Museum herbarium are now imaged and online!  Searchable at midatlanticherbaria.org.
 
High resolution image of this specimen can be found here: http://midatlanticherbaria.org/portal/collections/individual/index.php?occid=12232607&clid=0
 

Fall allergies causing you grief?  
 
Ragweed is a plant many people are (all too) familiar with.  Or at least their bodies are.  Common ragweed (Ambrosia artemisiifolia) is actually native to North America, but has been introduced across the world.  In many cases, this plant (or other ragweed species) are to blame for seasonal pollen allergies known as “hay fever.”  In summer and early fall, ragweed plants produce copious numbers of pollen grains, which are dispersed in the wind.  Don’t blame those insect-pollinated plants with showy flowers for your allergy troubles.  Wind pollinated plants like ragweed are your culprit. 
 
This ragweed specimen was collected by Bonnie and Joe Isaac in Lawrence county, Pennsylvania on October 8, 1995.  Bonnie is the collection manager in the Section of Botany at the museum, an active plant collector and field botanist, and an expert on the plants of Pennsylvania.
 
Although ragweed is native in the US, historical records (pollen deposited in sediment cores) suggest that this species was far less common in North America before European colonization.  This is perhaps not too surprising considering the species thrives in disturbed habitats that came with European colonization and urbanization.  A study published in 2014 by Martin and colleagues in the journal Molecular Ecology extracted DNA from nearly 500 historic herbarium specimens dating back to the 1800s to measure the genetic makeup prior widespread changes to the landscape in the late 19th century. Combined with data from recent collections, they found shifts in the genetic makeup of ragweed populations as the species was expanding in the United States. 
 
Read the study abstract here: https://onlinelibrary.wiley.com/doi/abs/10.1111/mec.12675