Pitcher plants: carnivorous survivors at Harvard Forest

Leaves were sailing off the oaks this morning as wind freshened from the northeast, bringing rain, sure enough by the afternoon. The big oak I am living with this year at the Harvard Forest is still holding onto a crown of leaves — take a look at the view from the Barn Tower phenocam of the canopy where it lives, and the tenacity of oaks and their leaves is apparent. Birches and maples have mostly lost their leaves but the oaks are holding strong.

Leading a spirited class of Mount Holyoke College students, Aaron Ellison, senior research fellow in ecology at the Harvard Forest, noted the survival strategy for these plants in the nutrient-poor bog. Carnivorous, pitcher plants trap ants for their main diet. Living as long as 100 years, it can be 10 to 15 years before they flower, making a look at these plants in full autumn splendor of the bog all the more special.

Walking the woods with John O’Keefe of the Harvard Forest this week, he noted, as Aaron also did today, how at this time of year the invasive plants really stand out.  While many native plants have lost their leaves, the extended season of invaders that gives them their wily edge makes these plants obvious in the late fall woods. Sure enough, non-native bittersweet greeted us with a botanical shout as we walked into the wood at Tom Swamp, where the trailhead bears the brunt of invasive plants. 

John has been tracking the seasonal progression of  same trees at the forest for 25 years and he said his hunch is when he works up the data at season’s end, fall will have come two to three days later this year than the long term average.

That is in keeping with the trend in which climate change has been extending the growing season, on average, with earlier spring and later fall.

Truth be told, much as I will miss them, the season’s big hammer for me falls not in the leaves…but in the clock change coming tonight, accelerating our slide to the shortest days of the year. All the better reason to revel in a nice fall walk in the bog. Here’s a map. Give it a try.