Much of Massachusetts was in some level of drought earlier this year. All other regions have since had enough rain to bounce back, but as of today, the Cape Cod Region is still classified as having “mild drought” conditions. Although there are numerous adverse impacts that result from a prolonged drought, one positive response is a big bloom year for the coastal plain pondshore plant communities, which thrive in the drawdown areas around pond perimeters in low water years. This plant community is comprised of herbaceous and graminoid (i.e., grass-like) species and typically establishes in coastal ponds that are directly linked to the underground aquifer and whose water levels are therefore linked to groundwater levels. As a result, the ponds’ water level rises and falls with the water table through the seasons, which in most years leaves exposed shores expanding throughout the summer. Drought conditions can result in a further expansion of this available pondshore habitat. 

Many of the plants within this community can germinate and develop perennial basal leaves while still inundated with water in the spring, expanding their growth as the pond dries and the water levels recedes into the summer. Other species may germinate only when exposed. In wet years when the pond level remains high, pondshore plants may grow vegetatively with little to no flowering, or they may not grow or germinate at all. According to the state’s Natural Heritage and Endangered Species program, only about one in every five years may be dry enough for the plants in this habitat to fully develop. 

This year was certainly one of those years. A walk around one coastal plane pond in Barnstable last week proved to be quite well timed, as many of the quintessential coastal plain pondshore plants were in full bloom. Below is a sampling of a few of my favorite finds: 

1. Plymouth gentian (Sabatia kennedyana) is a globally restricted but locally abundant species. The bright pink blooms ringing the entire pond definitely stole the show. This was my first time seeing this plant and it was spectacular. 

2. Slender arrowhead aka quill-leaved arrowhead (Sagittaria teres) has three-petaled white flowers and is the only species of arrowhead without broad, flattened leaf blades. It is mixed with common pipewort (Eriocaulon aquaticum) in the photo below. 

3. Rose coreopsis aka pink tickseed (Coreopsis rosea) has a discontinuous range in the eastern United States and Canada; it is found in Nova Scotia, MA/RI, NY/NJ/PA/DE/MD, and SC/GA, but not in the areas in between. 

4. Carolina redroot (Lachnanthes caroliniana) has a unique fan of flattened leaves, which somewhat resemble those of an iris, and tall flower clusters. Its name comes from its red-orange roots.

5. Golden hedge hyssop (Gratiola aurea) is a low-growing plant with bright yellow tubular flowers. It is mixed with common pipewort in the photo below.