Mason Heberling

Exactly 100 years ago, this specimen of pale jewelweed (Impatiens pallida) was collected by Otto Jennings - just across the street from the Carnegie Museum in a moist, narrow ravine in Pittsburgh's Schenley Park.  This specimen isn't just "any old" pale jewelweed.  Most pale jewelweed has bright lemon yellow flowers, but not always.  This specimen is a cream-colored form, formally described by Jennings in 1920 as Impatiens pallida forma speciosa. This particular specimen was referenced in his description of the cream-colored form, thereby making this specimen a holotype (that is, THE reference specimen for the taxon).  

To me, the difference in color is there, but subtle.  I'm not sure if the form is still "officially" recognized by most botanists or if much research has been done on flower color variation in the species.  But I am now keeping an eye out for it!

Photo by Greg Funka taken on August 27, 2019 in the type locality (Schenley Park)...100 years after Otto Jennings collected this specimen.

​Note the difference in color compared to photo below.

A couple of creepers: plant doppelgängers
 
Did you know that many plant species have doppelgängers?  Check out these two species, both collected at the same site on August 22, 1965 by David Berkheimer in Everett Borough (Bedford county), Pennsylvania. 
 
With its distinctive hand-like leaves, Virginia creeper (Parthenocissus quinquefolia) is fairly well known, or at least looks familiar by many.  It is a woody vine in the grape plant family (Vitaceae), common to forests, forest edges, and urban areas in across eastern North America.  It is one of those ubiquitous but overlooked plants. The species is just about everywhere, climbing high up trees. But upon closer look, there are two similar looking species in Pennsylvania. Although less commonly recognized (though not all that uncommon to find!), thicket creeper (Parthenocissus inserta) looks very similar.  (note: there is some confusion, with some botanists calling this species as P. vitacea, but either way, there are definitely two species here).
 
So what’s the difference?  There are two easy ways to tell the difference.  First, the species have differences in their tendrils (the structures that wrap around branches, attaching the vine to the tree it is climbing).  Virginia creeper has clear adhesive, swollen disks where the tendrils attach to the tree.  In contrast, thicket creeper does not have these. (But to confuse you, they rarely do).  Second, the flowering/fruiting structures are different. Thicket creeper has branching inflorescences (stem structures with flowers/fruits), often in two main axes, with noticeably larger berries than Virginia creeper. Virginia creeper has an inflorescence that branches, often in zig-zag, random looking pattern, but most importantly – with a clear central axis.
 
Below: (left) no adhesive disks on tendrils for thicket creeper; (right) adhesive disks connecting  tendrils to host tree. Not to be confused with "hairy" poison ivy vines.

A couple years ago, I was confident I could pick Virginia creeper out of a line up.  But I must admit, I didn’t even know until last year there was another species that looked like Virginia creeper. It was a mind-blowing moment, and pretty much dropped everything to go exploring for the two species. I’m always curious every time I see these vines to figure out which species it is.  It turns out, thicket creeper is more common than I thought around Pittsburgh, especially along the rivers.
 
Keep an eye out for these species this fall, when they have developed fruits to easily tell them apart.  And on top of that, they have some of the most bright red, beautiful foliage of any plant in our area!
 
Check out these specimens (and more!) here:
http://midatlanticherbaria.org/portal/collections/list.php?db=328&catnum=CM064196%3B+CM064039&othercatnum=1
http://midatlanticherbaria.org/portal/collections/list.php?db=328&catnum=CM064491%3BCM064471&othercatnum=1

Thanks for your impatiens! A day late post.

Two specimens of jewelweed, Impatiens, collected on this day (well, yesterday) by Carnegie Museum curator Leroy Henry in 1944 in Ben Avon Heights, near Pittsburgh.  There are two species of jewelweed commonly found in Pennsylvania and in relatively wet, partly shady habitats across eastern North America. They can form dense stands along wet roadside ditches at edge of woods and in floodplain forests.  Henry collected both species in the same location, as they commonly grow together.
 
What’s the difference between these two specimens?  Though less obvious in specimen form, the most noticeable difference is flower color.  Common jewelweed (Impatiens capensis), also called spotted or orange jewelweed, has orang flowers. In contrast, the flowers of yellow jewelweed (Impatiens pallida), also called pale jewelweed, are...well, yellow.  Flower os both species have distinctive nectar spurs that jut out of the back of the flower. It is entertaining to watch bumblebees go from flower to flower in a stand of jewelweed.
 
Jewelweeds are herbaceous, annual plants with juicy stems that can range in size, from short to very tall.  A widespread story is that jewelweed can treat skin irritations, and in particular, helps prevent poison ivy rash by rubbing jewelweed on skin after contact with poison ivy.  I don’t know of this being supported with data.
 
Jewelweed is also often called “touch-me-not” because the developed seed pods eject seeds out when touched. It can be a fun activity for kids (and adults).
 
Jewelweed flowers open mid-summer and the plants continue to flower until killed by autumn frost.
 
Jewelweed produces two types of flowers – the obvious ones with nectar spurs that are visited by bees and also, tiny inconspicuous flowers that do not open.  These small flowers are self-pollinating (cleistogamous).
 
Deer often eat jewelweed. A recent study found that some populations of the species that have historically received a lot of deer browsing have evolved greater tolerance to herbivory. https://besjournals.onlinelibrary.wiley.com/doi/full/10.1111/1365-2745.12344
 
I’m always amazed how sensitive jewelweed leaves are to the sun. When exposed to direct sun, their leaves get very droopy.  But they seem to quickly bounce back.
 
Impatiens commonly planted in gardens are related (in the same genus) but are not the same species.
 
Check out these specimens (and more!) here:
http://midatlanticherbaria.org/portal/collections/list.php?db=328&catnum=CM064196%3B+CM064039&othercatnum=1

​30 years ago today!:
A milestone for Botany at the Carnegie Museum
 
On August 7, 1989, Bonnie Isaac started at the Carnegie Museum. She was initially hired at the museum to work on a project to database the plant collection, making it searchable and therefore more useable to understand the occurrence and distribution of plants across Pennsylvania (and beyond). Since then, a lot has happened. Thirty years later, Bonnie is now Collection Manager in the Section of Botany and Co-chair of Collections.
 
It is no exaggeration to say Bonnie’s influence on the Section of Botany has been monumental.  And continues to be.

As one of the top plant collectors over the Carnegie Museum’s 120+ year history, she has actively contributed to the growth of the herbarium, collecting several tens of thousands of specimens from across Pennsylvania and North America. These specimens now reside in herbaria across the world and have are actively used by research across the world to make exciting discoveries.
 
Bonnie played a pivotal role in the digitization of the Carnegie Museum herbarium, one of the first of its size to have all specimens in the entire collection with label data entered into a database and publicly available online. A huge accomplishment that took over a decade of her career to complete, the collection database has increased the research value and led to an massive increase in specimen use. The digitization of the herbarium continues today through a project facilitated by Bonnie and funded by the National Science Foundation to make high resolution digital images and georeferencing (assign latitude/longitude to plot on a map) to all specimens collected in the region.
 
Although she’s humble about it, Bonnie is an incredible field botanist and leading expert on the plants of Pennsylvania, especially those rare and threatened species of conservation concern. An expert in natural history collections management and methods, Bonnie has a specialized diploma on herbarium techniques from Royal Botanic Garden, Kew, England. She has a master’s degree from Youngstown State University, where she studied the ecology and distribution of a rare species.
 
Bonnie’s science and botanical knowledge impacts conservation decisions. Since 2001, she has served as a member of the Vascular Plant Technical Committee of the Pennsylvania Biological Survey, serving at various times over the past decades as president and recording secretary, which advised the state in determining the status of endangered and threatened plant species. She is currently working on a project funded by the Pennsylvania Department of Conservation and Natural Resources through the Wild Resources Conservation Program, revisiting many historic sites of 10 threatened species across the state to assess their current rarity status.
 
Beyond the walls of the museum, Bonnie has a huge impact on botanical research in Pennsylvania and fosters a public appreciation for the role of plants in our lives and ecosystem health.  She is a founding member of the “Pennsylvania Botany Symposium,” a group of committed volunteers who provide education and networking opportunities for professionals, amateurs, and students of botany, including a biennial symposium that gathers Pennsylvania botanists of all levels. Bonnie is also very active in the Botanical Society of Western Pennsylvania, one of the oldest botanical organizations in the country.  She  has served as President of the organization since 2005.
 
And if that is enough – she is friendly, too!
 
Happy work-iversary, Bonnie!

This specimen of  common evening-primrose (Oenothera biennis) was collected by Mary Joy  Haywood along South  Fork Tenmile Creek in Greene county, Pennsylvania on July 19, 1993.  Haywood was a biology professor at Carlow College in Pittsburgh, and  President of the Botanical Society of Western Pennsylvania for many years. 

A "late" bloomer, so to speak.  Common evening-primrose is a fascinating and important plant (ecologically  and culturally).  Perhaps among the most interesting reasons, its bright yellow flowers quickly open in the evening and close by noon the next day. 

Common evening-primrose is also famous for its ethnobotanical uses, for food and as medicine.  Common  evening-primrose oil, derived from its seeds, has been used by  many in a variety of ways. It is often suggested by midwives to pregnant women in the last weeks of pregnancy to prepare and induce labor.

The species can be found in open habitats across the world. Native to eastern and central North America, it has been planted in  gardens across the world and has since become widely  naturalized.   It is also a common member of the urban flora, especially along sidewalks, even  often growing out of sidewalk cracks.

Teaberry - a Pennsylvania staple?
 
This specimen of eastern teaberry (Gaultheria procumbens), also called American wintergreen, was collected on July 12, 1963 by Leroy Henry (Carnegie Museum Curator of Botany at the time) and Dean Ross in a cranberry bog in Somerset county, Pennsylvania.
 
Perhaps best known by many as a unique wintergreen flavor of chewing gum and ice cream, especially in Pennsylvania.  Atlas Obscura calls Teaberry ice cream: “sometimes looks like Pepto-Bismol and smells like Bengay.”  Penn State Berkey  Creamery  as  the  “best treat of a bygone era.”
 
Teaberry is in the heath (blueberry) family, Ericaceae.  It is a small shrub growing along the ground, found across the Eastern US and distinctive evergreen leaves.
 
Find high resolution image of this teaberry specimen (and more) online here:
http://midatlanticherbaria.org/portal/collections/list.php?db=328&catnum=CM075420&othercatnum=1  

A plant popular during the Revolutionary War
 
Happy Independence Day! What better way to celebrate than with herbarium specimens of New Jersey tea (Ceanothus americanus), named for the fact that is was used as a substitute for tea by colonists and American soldiers during the American Revolutionary War. There was presumably a shortage of black tea, which were imported. Although the leaves contain no caffeine, it fit the bill. The plant also has a much longer history before European settlement.  Tribes of the Missouri River used the leaves for tea as well, and tribes of the Great Lakes used the plant to treat digestive ailments.  
 
New Jersey tea, also called Indian tea, can be found not only in New Jersey, but across the eastern United States.  It is in the buckthorn family (Rhamnaceae), which is unsurprisingly also family to introduced shrub/tree, common buckthorn  (Rhamnus cathartica).
 
These specimens  below were both collected in Pennsylvania on the 4th of July. 

One in Luzerne county by Alfred Twining 1907, who wrote a flora of Northeastern PA ten years later (https://archive.org/details/floraofnortheast00twin/page/n7).  Many of his specimens are at the Everhart Museum of Natural History, Science, and Art in Scranton, PA (http://sweetgum.nybg.org/science/ih/herbarium-details/?irn=165032).

The other Independence Day New Jersey Tea specimen was collected by Robert Leberman in Crawford county in 1986.  Leberman established the bird banding program at the Carnegie Musuem of Natural History’s Powdermill Nature Reserve in 1961.  It continues today as the longest running, year-round banding research operation in the country.  
 

New Jersey Tea is a beautiful shrub, important for many pollinators, and food source for other wildlife. The plant is also sold commercially by many native plant nurseries to plant in your yard or garden.
 
All plants have a cultural history and a scientific one. As you remember the signing of the Declaration of Independence and the American Revolution, think too about New Jersey Tea’s impact on our country. Did John Hancock drank it before signing? (Totally made that up).  
 
Find high resolution images of these specimens (and 290 more!) online: http://midatlanticherbaria.org/portal/collections/list.php?db=328&taxa=Ceanothus+americanus&usethes=1&taxontype=2

Some dogwoods for the dog days of summer
 
Who doesn’t love a good dogwood? Perhaps you are most familiar with flowering dogwood (Cornus florida), with the beautiful showy white flowers in woods and wooded roadsides across Pennsylvania in the spring.  Or perhaps, the commonly planted Japanese dogwood (Cornus kousa) from...you guessed it...East Asia.  But there are many different dogwood species, all in the genus Cornus.  Species in the genus are distributed across much of the temperate world in the Northern Hemisphere.  Rhoads & Block Plants of Pennsylvania list nine species found in the wild in our state.  They are trees or shrubs (with one exception). The veins on their leaves are quite distinctive, as is their bark and flower structures.
 
Why are these shrubs called dogwood?  There are several stories behind the unique common name. One is that the name was derived from the Celtic word “dag”, referring to its use of its nice wood as a dagger like tools or skewers. Another explanation is that the bard was once used as a treatment of mange for dogs.
 
Four dogwood species were collected on June 28 in Pennsylvania: 69,  37,  26, and 23  years ago:
 
Red-osier dogwood, Cornus sericea (aka Cornus stolonifera) June 28, 1950 in Erie County. Beautiful bright red stems.
 
Gray dogwood, Cornus racemosa June 28, 1982 in Blair County.
 
Cornus ammonum June 28, 1993 in Clarion County.
 
Cornus florida June 28, 1996.  White flowers from the spring are long gone.  (Well, the white structures aren’t actually petals, but modified leaves called bracts that surround a cluster of small yellowish flowers).
 
Over 2,600 dogwood (Cornus) specimens in the Carnegie Museum herbarium from across the world are available online, many with high resolution images: http://midatlanticherbaria.org/portal/collections/list.php?db=328&taxa=cornus&usethes=1&taxontype=2

Whoa, this plant will catch your attention!  Although towering in at up to 8 feet tall with leaves 2 feet wide, Cow parsnip (Heracleum maximum, aka Heracleum lanatum) is not a tree, but herbaceous (non-woody). This species is the largest member of the carrot family (Apiaceae) native to North America. It can be found along shaded roadsides, waterways, and edge of woods. Its flower structure consists of many small white flowers on short stalks connected at a single point – an umbrella of flowers - botanically known as an “umbel.” Umbels are characteristic of the carrot family (think of the perhaps better recognized Queen Anne’s lace, Daucus carota, which is also known as “wild carrot”).
 
These specimens were all collected on June 21– but years apart - on 1907 (Westmoreland county, PA), 1934 (Pittsburgh), and 1960 (Beaver county, PA).   
 
This species is often confused with giant hogweed. Cow parsnip is often confused for the non-native plant called giant hogweed (Heracleum mantegazzianum). Giant hogweed has hit the news media in past few years and on many people’s radar, as it is considered a significant public human health concern. This plant is highly poisonous and designated as a federal noxious weed.  The sap of giant hogweed causes “phytophotodermatitis,” meaning serious skin inflammation occurs when contacted skin is exposed to sunlight.  Skin rashes can be very severe.  The sap can cause temporary or permanent blindness. Cow parsnip has a similar set of chemicals in its sap, and although not as poisonous, be  careful around these plants.
 
Giant hogweed can be 8-20 feet tall with leaves up to 5 feet wide!  It is thought to be eradicated in Pennsylvania. Although similar to the Pennsylvania native species cow parsnip, giant hogweed is noticeably larger in height and flower size. (see herbarium specimen here – it took 6 sheets!)
 
See here for a nice comparison between these similar species. https://www.maine.gov/dacf/php/horticulture/hogweedlookalikes.shtml
 
Given the size of members of the genus, the name Heracleum (derivative of Hercules) is quite fitting.
 
Specimen records and images for this species in the CM herbarium are now publicly available online:
http://midatlanticherbaria.org/portal/collections/list.php?db=328&taxa=Heracleum+lanatum&usethes=1&taxontype=2

Not all bittersweet vines are invasive to Pennsylvania. This specimen was collected on June 14, 1965 by botany curator Leroy  Henry  in Clearfield county,  along  Rt 969. American bittersweet (Celastrus scandens) is a woody vine that  blooms in June, which turn to beautiful clusters of orange/red fruit in late summer/fall.  The species is native to eastern USA, found along open thickets/edge of woods.

American bittersweet (Celastrus scandens) might be easily  confused with the much more common Asian bittersweet (Celastrus orbiculatus).  There are two major visual  differences between the species: 1) flower/fruit --  native species has single terminal cluster of many flowers/fruits at tips of branches, whereas the invasive has flowers/fruits at axils of leaves (where leaves connect to stem; and 2) leaves -- native  species' leaves are more elongate, whereas the invasive species' leaves are more round, often even circular ('orbiculate').

American  bittersweet is no longer common in Pennsylvania, most likely taken over by the closely  related Asian bittersweet.   Asian bittersweet  is a relatively newer addition to the  flora of Pennsylvania, not showing  up  in  western PA and  the  Pittsburgh region until  the 1980s.  Given its abundance and distribution throughout the region  now,  it is hard to fathom it was not present only several decades ago.

Research over the past decade has shown that the invasive species hybridizes with the native, likely contributing to  the decline  of the native American bittersweet.

Keep a look out for American bittersweet in our region.  (I have  not  seen it in Allegheny county, although we have historic  records)

This specimen image is now publicly available online:
http://midatlanticherbaria.org/portal/collections/individual/index.php?occid=12131436&clid=0