May 19, 2006: 11 years ago today

  Collected on May 19, 2006, this specimen was found by Loree Speedy in a stream valley near the Mill Run Reservoir in Fayette County, PA.  This charismatic species (Arisaema triphyllum) is known as “Jack-in-the-Pulpit” and native to forests of the Eastern US.  Its common name comes from its flowering structure – a distinctive hooded structure (spathe) that looks like a pulpit and the flowers (spadix) that resembles “Jack,” the minister standing within. This flower structure is shared among members of the arum family (Araceae; members often called “aroids”), which includes the popular houseplants known as “peace lilies.”
 
The natural history of Jack-in-the-pulpit is fascinating.  For starters, individual plants can be male or female and the gender can switch from year to year! This species has intrigued botanists for decades and used as a study system to understand the ecology and evolution of plant sex expression.  Larger plants tend to have female flowers, but the exact size is dependent on environmental conditions and genetics of a given population.
 
Jack-in-the-pulpit has calcium oxalate in its leaves that can irritate skin and is poisonous to ingest.  It is generally avoided by deer.  However, recent research from the lab of Susan Kalisz (Research Associate at the museum) has shown that deer overabundance negatively affects the growth of this species. While it is rarely eaten by deer, they affect other environmental conditions, such as light levels and soil conditions. 

With over 870 specimens, this species is among the best replicated in the CM herbarium. However, there is some debate whether this species should be treated as multiple species or not.