Mason Heberling

This four-leaf clover was collected by our very own mollusk curator Tim Pearce on July 5, 2014 in Pittsburgh. Tim must be a lucky person, having found several other four-leaf clover specimens and now in the Carnegie Museum Herbarium. This particular specimen is white clover (Trifolium repens), a species native to Europe but common in lawns worldwide. Many clovers have three leaflets (hence the genus name “tri” – “folium”), but according to folklore, those uncommon plants with four leaves bring luck.
 
This lucky specimen was imaged recently (along with many others in the clover family, Fabaceae) and is publicly available online: http://midatlanticherbaria.org/portal/collections/individual/index.php?occid=21236224&clid=0
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What’s a shamrock? There is no overwhelming scientific consensus on which species is the well-known Irish national emblem.  There was survey of Irish botanists in the early 1890s asking which species was the “true” shamrock.  A similar survey was repeated in 1988.  The results suggest the shamrock is either Trifolium dubium (aka “lesser trefoil”) or Trifolium repens (aka “white clover”).  The plants commonly sold around St. Patrick’s Day as “shamrocks” or “4-leaf clovers” are in the plant genus Oxalis (“wood sorrel”), which belong to different plant family than true clovers.
 
Top left: Trifolium repens (collected 1974 in Louisiana), aka “white clover”
Top right: Trifolium  dubium (collected 1961 in Pennsylvania), aka “lesser trefoil”
Bottom left: Oxalis tetraphylla (collected 1981 in India), aka “lucky clover,” although not a true clover
Bottom right: Oxalis debilis (collected 1989 in cultivation), aka “pink woodsorrel”
 
These specimens were recently imaged (along with many others in the legume family, Fabaceae) and are publicly available online: http://midatlanticherbaria.org/portal/collections/list.php?db=328&hasimages=1&includecult=1&taxa=trifolium&usethes=1&taxontype=2
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Don’t touch that! This leafless specimen of poison ivy (Toxicodendron radicans) was collected by C.H. Morgan on March 11, 1922 near Port Vue (near McKeesport just outside of Pittsburgh). Although best admired from a distance, poison ivy is a remarkable plant.  And like it  or not, a plant that has become a part of our urban landscape.  The leaves can be spectacularly red colored in the fall with beautiful berries. But still, do not touch. Not all of us are allergic to poison ivy, but even if you don’t think you are, you can become sensitive to it in time.  (From experience, getting the rash on your fingertips is not fun at all...)
 
All parts of this species are considered poisonous, containing the group of chemicals causing that nasty rash in humans, urushiol. Only humans are susceptible to the rash, as poison ivy is eaten by other animals. Getting it on your skin can be painful. The oils can also be inhaled (when burning wood) and cause serious respiratory illness or damage to eyes.
 
This particular specimen may not have leaves like most herbarium specimens, but check out the impressive aerial roots on the left. Poison ivy is a trailing or climbing vine (or even shrub) that can be quite diverse in terms of leaf shape and growth habit. In addition to its distinctive leaves of three, climbing plants have noticeable aerial roots, adhering the vine to the bark of host tree.
 
Why does poison ivy produce urushiol?  The answer is not totally clear, but probably not to deter humans, but instead as an antimicrobial agent.
 
Note the specimen label reads “Rhus toxicodendron.”  Although  the species is related to sumac (which are in the genus Rhus), poison ivy is now recognized in a separate genus, Toxicodendron, which means “poison tree.”
 
Poison ivy is native to North America. The species in the cashew plant family (Anacardiaceae), which includes several other species which produce skin irritants. In addition to poison ivy, poison oak, and poison sumac, the family also includes mango and cashew.  Interestingly, the shell of the cashew nut contains chemicals that can cause similar allergic skin reactions as poison ivy.
 
Research indicates that poison ivy may be doing better in a warming world, both in terms of growth and producing higher quantities of forms of urushiol particularly toxic to humans. Poison ivy also  tends to do well in disturbed environments, such as urban areas.
 
This specimen image (and all other poison ivy specimens in the region) are available online: http://midatlanticherbaria.org/portal/collections/individual/index.php?occid=12232543&clid=0

Do you think Punxsutawney Phil was ever overcome by the beauty of this very violet 71 years ago? 

Or perhaps he nibbled off a leaf or two? 

After all, legend has it that Phil is over 100 years old! This specimen of Labrador violet (Viola labradorica) was collected near Phil’s home in Punxsutawney , Pennsylvania on June 2, 1948 by Carnegie Museum botany curator Leroy Henry.
 
In case you wondered, on Groundhog Day 1948, Punxsutawney Phil saw his shadow and predicted six more weeks of winter.
 
This specimen was imaged recently (along with many others in the violet family) and is publicly available online: http://midatlanticherbaria.org/portal/collections/individual/index.php?occid=11964316&clid=0

 Collected on this Day in 1927
 
Well, collected on this month.  Maybe this day, who knows? 

The distinctively hairy twigs with large bud scars of staghorn sumac (Rhus typhina) collected in January 1927 by Amy Neale in “dry soil” in Kittanning, Pennsylvania (Armstrong Co).  I’m not sure what motivated this collection or unfortunately, much about Amy Neale.  The Carnegie Museum herbarium has 261 specimens collected by Amy Neale, all near or in Kittanning, PA.  
 
You can  see these collections here: http://midatlanticherbaria.org/portal/collections/list.php?db=328&collector=neale&page=1
 
All of these specimens will be imaged in the next two years.
 
Staghorn sumac is an early successional small tree that is native to PA and often grows in clusters along highways, old fields, and other open habitats. Its twigs and fruit are distinctive, especially in winter --- a classic part of the Pennsylvania landscape in my opinion! It is often viewed as a “weed” or “junk tree” with cheap, fast growing stems.  But it is an incredible plant.
 
I’m always intrigued by specimens of twigs collected in winter.  There are several collectors in Western Pennsylvania who collected dozens to hundreds of such specimens.
 
This specimen image is now publicly available online: http://midatlanticherbaria.org/portal/collections/individual/index.php?occid=12232636&clid=0


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Check back for more! Botanists at the Carnegie Museum of Natural History share digital specimens from the herbarium on dates they were collected. They have embarked on a three-year project to digitize nearly 190,000 plant specimens collected in the region, making images and other data publicly available online. This effort is part of the Mid-Atlantic Megalopolis Project (mamdigitization.org), a network of thirteen herbaria spanning the densely populated urban corridor from Washington, D.C. to New York City to achieve a greater understanding of our urban areas, including the unique industrial and environmental history of the greater Pittsburgh region. This project is made possible by the National Science Foundation under grant no. 1801022. ​

Black maple (Acer saccharum ssp. nigrum) collected by Herbert W. Graham on January 15 , 1927 along Big Sewickley Creek, just outside of Pittsburgh.  Black maple is sometimes considered is own species (Acer nigrum), depending on who you ask.

Who doesn't love a good herbarium specimen of sticks collected in winter?  We have quite a few specimens collected in Pennsylvania during winter when the species is leafless.  It is unclear exactly why they were collected in every instance, but it was likely for reference material to help with species identification in winter.  The downside is that specimens without leaves and/or reproductive structures can be difficult to definitively identify.  But what specimen is "perfect" anyway?

 
Around 25-30 million cut trees are sold each year in the United States for the holidays. The popularity of certain species for this use has changed through time.  Many different evergreen conifer species are cultivated in the US for decorative use during the holidays.  Needle length, softness, retention, color, and even scent vary by species or variety. Similarly, branching characteristics and branch strength differs by species. Plus, some species grow faster and easier than others, which means some species are cheaper.
 
This specimen of Fraser fir (Abies fraseri) was collected in Philadelphia at the Thomas Meehan & Sons Nursery.  The person who collected this specimen and the date of collection are unknown.  Thomas Meehan immigrated to the United States from England in 1848 and started a landscaping business.  With his three sons, he started the Thomas Meehan & Sons Nursuries in 1896.  The nursery was unique in that it specialized in native trees and shrubs, unlike most nurseries that focused on European and Asian varieties (still very common today).  The nursery closed in 1916.
 
Fraser fir is currently one of the most popular Christmas trees.  It is known for its dark green color, soft needles, stiff branches (great for hanging heavy ornaments), and has good needle retention.  Unfortunately, native to the Southern Appalachians, Fraser fir isn’t the easiest to grow in Pennsylvania.
 
Before farms began cultivating trees for that purpose in the early 20th century, people just went to the woods to cut down their tree for the holidays.   Some of the earliest Christmas tree farms in the US started in Indiana County, PA as early as 1918.  Many farms in the region turned their fields into Christmas tree farms as it became profitable. By 1960, more than 1 million trees were harvested per year in Indiana County alone.  The harvest in Pennsylvania has declined for several reasons, including increased popularity of artificial trees and consumer interest in Frasier fir trees (grows slower in PA than farms in North Carolina).  However, Pennsylvania is still among the top five states in terms of both number of working Christmas tree farms and trees harvested. According to the National Christmas Tree Association, 31,577 acres in Pennsylvania are used as Christmas tree plantations. Many of the Christmas tree lots in southwestern PA get their trees from farms in Indiana county.
 
This specimen image is now online and publicly available here:
http://midatlanticherbaria.org/portal/collections/individual/index.php?occid=11736894&clid=0
 

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