Collected on March 24, 1945, this specimen was found by Leroy K. Henry in North Park, just outside of Pittsburgh. Leroy Henry was an influential curator of botany at the museum from 1937-1973 and specialized in taxonomy and ecology of fungi in the region. Big-tooth aspen (Populus grandidentata) is a tree native to northeastern North America. Aspen produces small flowers on hanging clusters known as catkins.
Why collect and preserve a specimen that has no leaves? Since this species flowers in the early spring before it
leafs out, one reason is to be able to collect flowers for further scientific study. Flowers for this specimen are stored in the rectangular envelope in the lower right of the sheet. Along with hundreds of other specimens, this information can be used to understand how flowering dates change through time as a result of climate change. Scientists are using these specimens in ways the original collector never imagined.
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!