An illustration of a tiger beetle from Carnegie Museum of Natural History’s collection.
Hidden Collection
Section of Mollusks Tours
Did you know that the Section of Mollusks Assistant Curator Tim Pearce has been conducting monthly behind-the-scenes tours for the public since 2007?
On these tours, participants often learn for the first time that the museum has huge collections and scientists who conduct
research, and they see crowd pleasers such as the killer sea snail, the giant clam, and they look through the shell to see the beating heart of a live land snail.
Check our Section of Mollusks for tour times!
Think the papers in the back of your file cabinet are old?
Carnegie Museum of Natural History has pressed and preserved plant specimens on paper that were collected way back in 1754!
The specimen above is one of the oldest specimens in the herbarium. It is pot marigold (Calendula officinalis) that was collected in France in 1754 by Michel Adanson, an influential naturalist.
Collected on Christmas Eve 1883: Mistletoe
John A. Shafer bought this mistletoe at a market in Pittsburgh, Pennsylvania on Christmas Eve 1883. Sixteen years later, Shafer became the museum’s first botany curator. This mistletoe’s scientific name is Viscum album.
Mistletoes refer to many species within the genus Viscum. Usually, mistletoes refer to a species native to Europe, Viscum album. (“Album” is Latin for white.) European mistletoe has a deep cultural history, dating back to ancient Greece. It remains a well-known holiday decoration today.
Mistletoes are Hemi-Parasitic
Did you know that mistletoes are hemi-parasitic plants? They grow on the branches of trees like oaks, with special roots (called “haustorium”). These roots penetrate host trees to obtain water and nutrients. However, mistletoes don’t get all of their nutrients from their host plants. Hemi-parasitic plants like mistletoes make some of their own nutrients. They do this like other plants, through photosynthesis.
Mistletoe Germination
How do mistletoes germinate high up on the branches of trees? They have evolved to produce berries which birds like to eat. Birds then fly around, land on another branch, and poop viable mistletoe seeds. Without the help of birds, the seeds would likely just fall to the ground.
Mistletoes are native to the United States, too. American mistletoe (Phoradendron leucarpum) is native to southeastern states. People harvest and and sell this species in the United States in Christmas traditions, just like European mistletoe. The plant below is part of the museum’s herbarium and is from South Carolina in 1968. This specific American mistletoe had more than one host plant, all oak trees.
Botanists at Carnegie Museum of Natural History share pieces of the herbarium’s historical hidden collection on the dates they were discovered or collected. Check back for more!
Collected in December 1928
Are you decking your halls with boughs of holly? This specimen of American holly (Ilex opaca) was collected by M.L. Bomhard in Mandeville, Louisiana by on December 8, 1928. The holly revered for its holiday cheer usually refers to a related European species, Ilex aquifolium. But there are native holly species in North America that are equally (if not more) cheerful. Like most other hollies, American holly is dioecious, meaning it has male and female flowers on separate plants. Only the female plants have the characteristic bright red berries we all know and love. American holly stands out as one of the few broadleaved evergreen trees native to the Eastern United States (i.e., has green leaves during winter that are not needles). This species is near the northern edge of its range in Pennsylvania and is more common in southern states. It is listed in PA as a species of “special concern” due to its relative rarity.
Botanists at Carnegie Museum of Natural History share pieces of the herbarium’s historical hidden collection on the dates they were discovered or collected. Check back for more!
Indiana, Pennsylvania: Christmas Tree Capital of the World
Did you know that Pennsylvania is one of the top states for Christmas tree farms? In fact, southwestern Pennsylvania’s very own Indiana County is known as the “Christmas Tree Capital of the World.” According to the Indiana County Christmas Tree Growers’ Association, the title arose in 1956, when an estimated 700,000 trees were cut that year in the county.
Believe it or not, there are no Carnegie Museum specimens from Indiana County collected in the month of December. This is not all that surprising, as most specimens aren’t collected in the winter.
These Pennsylvania specimens shown above were collected sometime in December (exact day unknown): White Pine (Pinus strobus) in Kittanning in 1926 and Scots Pine (or “Scotch Pine”; Pinus sylvestris) from cultivation in
Avalon in 1902. Both species are cultivated and used as decorative trees for the holidays, but less commonly than in the past. Many different evergreen conifer species are cultivated in the United States 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.
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 first Christmas tree farms in the United States started in Indiana County 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 (Abies fraseri; which are native to the southern Appalachians and grows slower in Pennsylvania 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 Pennsylvania get their trees from farms in Indiana County.
Botanists at Carnegie Museum of Natural History share pieces of the herbarium’s historical hidden collection on the dates they were discovered or collected. Check back for more!