Participation: Dandelions and Pollinators!

Much of Cohasset is composed of public parks heavily dominated by nonnative grasses. Within these spaces, there are very few native organisms, as so-called "weeds" from Europe attempt to outcompete lawn grass.

Dandelions, for example, were brought to New England by Puritans in the 17th century to be used as a salad green. Versatile and highly competitive, the common dandelion soon spread throughout the New World, and can be found in Canada, South America, and throughout the United States (Dara 2006).

Since this plant has been establishing itself in New England for over 400 years, studying interactions with native species seemed like a good place to start! 

The study area itself is Wheelwright park, located at the edge of a disturbed forest. Dandelions were plentiful here, as were pollinators:

 Sweat bees were by far the most common visitor. At least 10 were spotted pollinating on individual flowers. These two above are likely Poey's furrow bee (Halictus poeyi), a native species. 


A larger sweat bee is Lasioglossum leucozonium, which is an introduced species from Europe.



Another Halictus native sweat bee of a different species. 

Lygus lineolaris, or "tarnished plant bug," native species.

Fly in the Muscina genus; native.

Halictus scabiosae, European

Native Pollinators Observed: 6

Nonnative Pollinators Observed: 10

Source:

Hourdajian, Dara. (2006) Introduced Species Summary Project: Dandelion (Taraxacum officinale). Columbia University. Retrieved from:  http://www.columbia.edu/itc/cerc/danoff-burg/invasion_bio/inv_spp_summ/Taraxum_officinale.htm