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Friends Battle the Purple Plague at Sunkhaze Meadows Refuge

March 11th, 2013

By: Danielle D’Auria, Friends of Sunkhaze Meadows National Wildlife Refuge

One of the most enjoyable streams to kayak within 15 miles of downtown Bangor is Sunkhaze Stream at the heart of the Sunkhaze Meadows National Wildlife Refuge (NWR) in Milford. It is a slow moving stream that from the north first winds and re-winds through shrub-scrub, then opens up amidst a vast flooded meadow. After entering the canopy of a silver maple floodplain forest, it empties almost unnoticed into the Penobscot River. In fact, “Sunkhaze” is an Abenaki word that means “concealing outlet.” Five miles of Sunkhaze Stream plus 12 miles of its 7 tributaries serve as a web connecting a variety of wetland types, including the second largest peat bog in the state. This unique wild area can feel so remote to its visitors, yet it cannot escape the plague of invasive species, namely the “purple plague”, also known as purple loosestrife (Lythrum salicaria).

Invasive purple loosestrife growing along Sunkhaze Stream (Caleb Slemmons, UMaine School of Biology and Ecology)

This “beautiful” vibrant purple ornamental brought here from Europe in the 1800’s, is a hardy perennial, herbaceous plant that spreads quickly in wetlands, destroying habitat and important food sources for native fish and wildlife. As with all National Wildlife Refuges, wildlife habitat is top priority at Sunkhaze Meadows. Thus the Refuge staff and Friends of Sunkhaze Meadows NWR have been working diligently to keep purple loosestrife out of the Refuge – and out of the extensive and remote wetlands of Sunkhaze Stream where detection and treatment could be more challenging.

I am not sure when it was first spotted on or immediately adjacent to the Refuge, but it is something that the Friends group has been paying close attention to for at least the past seven years. At first, there were just a few flowering plants found in isolated locations primarily along the roadside ditches that border the Refuge and few locations along public trails. Every year, we would round up volunteers in late July and early August to hand-pull and double-bag the plants for disposal. But in 2010, we suddenly became more concerned. The construction that had taken place on the County Road over the previous year seemed to have increased the loosestrife to a level that was no longer manageable with hand-pulling. Not only were there more plants in more locations, but many were newly sprouted and extremely difficult to find. We don’t know if the increase was due to the disturbance of the construction activities alone or contaminated gravel, hay or other construction materials brought in to the site. We did know that we needed a new plan of attack.

In 2011 and 2012, we turned to herbicides. We worked with the US Fish and Wildlife Service to get a Pesticide Use Permit in place, obtained permission from landowners along the right-of-way, and hired a contractor to instruct and oversee the spraying of glyphosate (the active ingredient in Roundup) with hand-held backpacks. We first flagged all infestations so that the spray crews could focus on spraying rather than searching for plants. After the plants died, we then returned and cut off the flower heads to make sure that little or no viable seed would hit the ground.

volunteer removing purple loosestrife

Friends volunteer, Lindsay Seward, with invasive purple loosestrife removed from Sunkhaze Meadows National Wildlife Refuge

We have been tracking the size and locations of the infestations over the past 3 years but cannot yet detect any reduction of the infestations.  The distribution of purple loosestrife seems to shift a bit from year to year, so maybe we are working to exhaust the seed bank. As with many battles against invasives, this one will surely take a lot of time, patience, persistence, and creativity. We may never win, but we hope we can reduce the infestations and prevent infestation of the most valuable sections of the Refuge. Unfortunately two large flowering plants were found in isolated locations deep in the Refuge along Sunkhaze Stream in 2011. We hand-pulled those and did not see any along the stream in 2012. We will need to be vigilant and the more eyes we have out there, the better. Thus, we invite you to visit Sunkhaze Meadows every summer. Enjoy a hike or relaxing paddle, but be sure to keep that purple search image in the back of your mind the whole time. Then, don’t forget to tell us about it!


While the Friends group continues to work on monitoring and removal of plants, we greatly appreciate additional location information on loosestrife to help combat its spread and volunteers are always in need.  Please contact us at:

The Friends group has developed at brochure entitled “The Purple Plague: What to do and Why…

For more information about the Refuge or the Friends group, visit us at or connect with us on Facebook:

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