July 26, 2012
As part of an ongoing effort to control the spread of the beautiful
but invasive wildflower Purple Loosestrife (Lythrum salicaria)
in the wetland to the north of Little Fresh Pond, the Cambridge Water
Department has, since 2007, annually purchased and released several
thousand Galerucella beetles in the area. These tiny insects
eat only the leaves and flowers of Purple Loosestrife.
This year, for the first time, it appears that the beetles have had
a significant impact. The loosestrife plants are not as tall or as dense
as they were in the past. It also appears that Common Cattails (Typha
latifolia), originally the predominant plant in the wetland, are
making a comeback.
Photos (top to bottom) show the loosestrife with cattails in the background,
a closeup of Purple Loosestrife, the newly opened container of 5000
beetles, and the team who released the beetles and surveyed the plants.