Tuesday, August 8, 2017

Newton’s Lost Wetlands and Buried Brooks

Posted by Richard B. Primack


“As in many countries precious metals belong to the crown, so here natural objects of rare beauty should belong to the public.” -Thoreau in his Journal, 1861

Until about 120 years ago, Newton, MA, was filled with wet meadows, marshes, and swamps, connected by miles of brooks. Where did they go? In an article published June 7 in the Newton Tab, I explain how over the past two centuries, as Newton changed from farming to industry, and then to a Boston suburb, developers and town workers buried brooks in culverts or put them into channels. Wetlands were filled in and became the sites of playgrounds, schools, other public buildings, and residential neighborhoods. The forgotten brooks and wetlands of Newton are periodically remembered when basements, streets, and playgrounds become flooded after heavy rains. 


Modified 1892 drainage map showing the main brooks and associated wetlands, with the current position of some schools and village centers and the Newton Library. Map by Matt Rothendler.

Many New England towns are revisiting past decisions to bury and channelize brooks. Some towns are uncovering buried streams and removing the vertical walls of channels, allowing streams to re-integrate with wetlands. Restoring brooks to something closer to their original condition and adding natural vegetation could help clean the brook’s water, reduce flooding, provide natural water features, and improve the recreational value of playgrounds, parks, and neighborhoods. 


Cheesecake Brook appears wild and well-integrated with the surrounding forest along Fuller Street.

Returning brooks to their natural state is expensive in the short term, but in the long run the economic, environmental, and recreational benefits to the people and businesses of Newton might be worth it. After a long history of channelizing and burying brooks and filling in wetlands for development, Newton’s future could benefit from undoing some of its past. 

Cheesecake Brook is channelized and separated from natural habitat along Albemarle Road. 


Wednesday, August 2, 2017

Leaf Longevity at the Arnold Arboretum

Posted by Linnea Smith and Sarah Pardo

Hi! We are two new members of the Primack lab: Linnea Smith (yes, like Carolus Linnaeus), an undergraduate at Boston University who’s joined the Primack lab for the summer with funding from the BU UROP program; and Sarah Pardo, a rising senior at BU Academy.

Linnea and Professor Primack doing fieldwork at the Arnold Arboretum

We are investigating how many years evergreen plants at Harvard University’s Arnold Arboretum retain their leaves, and why. Ecological theory suggests that a leaf stays on the branch, photosynthesizing, until it’s made a profit on the energy that went into making it. We want to determine if the amount of time a leaf remains on a plant is more influenced by the original environment in which the plants grow, or their evolutionary history.


Professor Primack and Sarah examining pine needles in the field

When tree branches begin growing in the spring, a scar is formed on each twig where bud growth had halted the previous winter. By counting the number of scars, we can determine the number of years of twig growth and leaf formation on a tree branch. For example, say a twig has leaves on seven scar-separated segments and no leaves on the eighth segment or beyond. This tells us that leaves stay on that twig for seven years. So far we have evaluated 173 species including conifers such as pines, firs, spruces and hemlocks and other evergreens like rhododendrons and hollies.


Showing seven years of growth on tiger tail spruce at Arnold Arboretum

We’ve both really enjoyed our work in the Primack lab so far and appreciate the warm welcome we’ve been given!