Here’s a look at six native shrubs and trees you can find blooming along forest edges in the lower Susquehanna valley right now.
The Black Locust (Robinia pseudoacacia), a member of the pea or legume family (Fabaceae), can be a dominant pioneer plant of sunny successional habitats, particularly on poor soils. Nodules along its roots fix nitrogen to help facilitate the growth of the intermediate and climax species of trees and shrubs that replace the pioneers. Initially armed with protective spines to reduce browsing, the Black Locust’s branches become mostly thornless as the tree matures.The Pinxter Flower, also known as the Pink Azalea, is certainly a contender for our most spectacular native blossoming shrub;……this Spicebush Swallowtail seems to like it too.When in bloom, the Black Cherry is a common sight in regional woodlands. Often seen already covered with blossoms when young and shrub-like, many of these trees will continue flowering and producing fruit throughout the decades required to reach a mature height of 60 feet or more.The Blackhaw is an understory shrub preferential to sun-dappled areas beneath a break in the forest canopy. Pollinated flowers later produce clusters of blue-black berries for birds and other wildlife.It’s easy to overlook the flowers of the Common Pawpaw. By the time the leaves are fully emerged and casting shade, blooming time is over.Nowadays, the Flowering Dogwood is most frequently encountered as a transplanted cultivar in city and suburban landscapes. In the wild, it is sparingly distributed throughout the region’s deciduous forests. These slow-growing little trees produce bright red berries that are quickly seized by a variety of birds upon ripening in the fall.
Local old timers might remember hearing folklore that equates the northward advance of the blooming of the Flowering Dogwoods with the progress of the American Shad’s spring spawning run up the river. While this is hardly a scientific proclamation, it is likely predicated on what had been some rather consistent observation prior to the construction of the lower Susquehanna’s hydroelectric dams. In fact, we’ve found it to be a useful way to remind us that it’s time for a trip to the river shoreline below Conowingo Dam to witness signs of the spring fish migration each year. We’re headed that way now and will summarize our sightings for you in days to come.
Tree blossoms open in response to the presence of adequate moisture and exposure to the warming effects of sunshine. Shad ascend the Susquehanna to spawn in response to suitable river flow and increasing water temperature. Sun and rain in the appropriate proportions can often conspire to synchronize otherwise unrelated events. Hence, a Flowering Dogwood in bloom along the edge of a mature forest means it’s time to go check out the shad run.
