The Carlisle Mosquito Online

Friday, November 25, 2005


biodiversity corner

Cranberries (Photo by Kay Fairweather)
Name: The cranberry is Vaccinium macrocarpon. It is a native plant in the same genus as blueberries — Vaccinium angustifolium is the lowbush blueberry. Macro means large and carpon means fruit so the cranberry is a Vaccinium with large fruit. I assume they were thinking of size relative to other members of the genus or relative to the size of the plant. The cranberry is a member of the heath family.

When and where seen: Not counting the Cranberry Bog on Curve Street where cranberries are cultivated, you can see a small patch of wild cranberries in the low-lying wetter parts of Towle Field, and large patches in Great Meadows Wildlife Refuge near the Greenough land. Right now the berries are gone but the plants are recognizable from a distance by the maroon color they take on. It is the same sort of purplish hue of bramble leaves in the fall. There are some sandy stretches in the wildlife refuge where most vegetation has died back and the ground is reddish-purple with the brambles and the cranberry plants.

Identification: The cranberry plant is a woody vine with runners from one to six feet long. It has vertical stems called uprights coming off the runner. There are little oval leaves on both the runners and the uprights. The plant blooms in late June or early July with flowers that are up to half an inch across with four white petals curved back on the flower stalk exposing the long orange-red stamens. The flowers are borne mainly on the uprights. They are pollinated by insects. Those honey bee hives at the Cranberry bog are home to the bees that pollinate the crop. The unripe berries are whitish; they take on the characteristic red color around September; in all they need about 80 days from pollination to maturity.

Did You Know? During the cranberry harvest in the bog on Curve Street around mid-October, you can buy beautiful fresh dry-harvest cranberries at the bog. These are superior to any other cranberries I have had. You can also buy Cranberry Bog honey, which from the cranberry point of view is a highly processed food, but from the human point of view it is a totally natural blend of cranberry and other bog plant pollens and nectars made into a delectable concoction by the bees.

Did you know? Unlike most berries that get soft when they are ripe, cranberries bounce, which is the origin of another common name — the bounce berry.

Thanksgiving: Every year I am thankful that I live in a town like Carlisle where we can so easily connect with the wonders of nature, the kind of place that has both wild and cultivated cranberries, and now a place with a farmers market. I'm thankful for open spaces to walk, like the cranberry bog, and I'm thankful for the people who pick up after their dogs and I wish there more like you. I'm thankful to the town for providing plastic bag dispensers and I wish more people took advantage of them. Oh, I seem to have digressed. Well, I'm also thankful for berries that bounce — how dull life would be if they all went splat.

Unripened cranberries, above, are white during the summer at Great Meadows Wildlife Refuge in Carlisle. (Photo by Steve Tobin)
Unripened cranberries

References: Brooklyn Botanical Garden at (search on cranberry); U Mass Cranberry Station at

Send your ideas for the biodiversity corner to Kay Fairweather at or feel free to use the space for your own article about nature in Carlisle.

2005 The Carlisle Mosquito