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But, why???

Why trees change colors

Not all birches are the same

Purple glitters

Poison Ivy

Good fences, good neighbors

Water rules

Pruning sense

Don't try this at home!

Friends and foes

Cold facts

Attention please

Purple Glitters

Purple loosestrife, an herbaceous perennial with showy purple flowers, is often a familiar sight in late summer within the wet areas and marshes of Massachusetts. It is especially noticeable in shallow water marshes and along vast stretches of waterways, such as the Charles River. What may not be commonly known about this prolific bloomer is that it is not native to our area. In fact, this invasive species has become a problem, displacing many native plants to the detriment of wildlife.

Although the first appearance of the European native (Lythrum salicaria) is unknown, it became established in the estuaries of northeastern North America by the early 1800s. By the late 1800s, purple loosestrife had spread throughout the north-east, but caused few problems until the 1930s, when it became aggressive in the flood plain pastures of the St. Lawrence River. Since then, the plant has steadily expanded its local distribution and now poses a serious threat to emergent, indigenous vegetation.

The plant was inadvertently spread by several methods. Loosestrife was often hidden in the fleece of sheep and in shorn wool, which was widely imported in the early and mid- 1800s when Boston was the center of the wool trade.

Ship ballast was another source of infestation. Ships sailing from Europe with light loads of wool, people, or goods required ballast in the hull to have the necessary stiffness and trim for efficient sailing on their westbound passage. This ballast was commonly moist sand from the tidal flats and often contained plant seeds. The ballast was dumped in North America and heavier cargo was loaded for the return trip.

Purple loosestrife is tolerant of many soil types, climates, and has no natural enemies. Therefore, once introduced to our area, it grew with abandon. Accordingly, with frightening speed, loosestrife now out-competes native vegetation and quickly establishes as a monoculture.

Loosestrife displaces native vegetation from the wetland ecosystem. Because the foreign species are not a suitable food source, this causes significant problems for wildlife populations. Thus the challenge of containing and eliminating this plant is currently being undertaken. In an effort to find effective control measures, an insect has been imported and introduced to infested areas. One of the biological controls currently being researched is the black marginal loosestrife beetle (Glerucella calmariensis). In areas where this beetle has been introduced, loosestrife has been reduced 70 - 90 percent.

Foreign species can become problems when introduced to environments that lack many of the normal checks and balances present in native environments. By bringing obligate predators to this country, naturalists are beginning to control purple loose-strife spread, and are helping to bring nature back into balance.