IDENTIFYING CHARACTERISTICS: Jacob's ladder is named for the arrangement of its 15 to 21 narrow egg-shaped leaflets. Clusters of blue-purple bell-shaped 3/4 - inch flowers top the erect 1- to 2-foot stems. Jacob's ladder is often mistaken for the more common, Greek valerian (Polemonium reptans), which is smaller and has stamens that do not protrude from the flower. Jacob's ladder is much larger and has stamens that extend beyond the petals. BIOLOGY-NATURAL HISTORY: Members of the Phlox Family (Polemoniaceae), both Polemonium species occur in Pennsylvania. While the more common Greek valerian grows in rich moist woods, Jacob's ladder is limited by its special wetland habitat requirements. Jacob's ladder blooms in June and July. PREFERRED HABITAT: Jacob's ladder is found in open, acidic peatlands in mountainous areas of Vermont, New York, Pennsylvania, Maryland and West Virginia. REASONS FOR BEING ENDANGERED: Wetland alteration and destruction are the primary reasons for this species' decline. Collecting by gardeners has added to the problem. Jacob's ladder is considered threatened throughout its natural range. Although five locations have been reported in Pennsylvania, only one population, of about 150 plants, remains intact. In fact, this species was thought to have been lost from our flora until the Morris Arboretum field team found a site in 1986. A western Pennsylvania population was destroyed by the creation of a man-made lake in 1966, which flooded its high mountain bog habitat. A second location in eastern Pennsylvania is thought to have been lost due to wetland draining for agricultural purposes. Searches for remaining sites continue, although historical information is sketchy. MANAGEMENT PROGRAMS: Jacob's ladder is a candidate for listing as endangered or
Invertebrates | Birds & Mammals | Fish, Reptiles & Amphibians | Plants
|
