Monthly Archives: June 2014


Scots Pine is an evergreen tree native to Europe and Asia. “Scotch pine has the largest geographic range of any pine, from Great Britain, Ireland, and Portugal east to eastern Siberia. It grows above the Arctic Circle in Scandinavia and south to the Mediterranean”.  Mature stands of Scots Pine found in Europe are often quite beautiful, as the trees have a symmetrical shape (think Christmas tree!) and distinctive red-orange bark.

They rarely do so well here, though. Easily turned by wind and weather, unless grown in the controlled environment of a tree farm, Scots Pine is usually a crooked, misshaped tree.


An invasive, non-native species like Scotch pine is a problem. Not only does it spread into open areas, but it displaces other native species. Scots pine is susceptible to disease and insect problems that can then infect native pines.

One of only three pine species on Beaver Island, Scots pine has very short, twisted needles (no more than two inches long) that occur two in a bundle. This makes it easily distinguishable from our native pine trees:the white pine has five needles in a bundle; the red pine, also native, has needles – two in a bundle – that are four to five inches long.

Once again, awareness is the first step in maintaining our precious landscape.




Marsh Thistle.

Cirsium Palustre.

European swamp thistle.

Marsh plume thistle.

Many names for yet another invasive plant species.

This one has been described, “like purple loosestrife, with spines.”

Marsh Thistle is a member of the Aster family with origins in Europe.

It is an erect herbaceous biennial that can grow 3 to 5 feet in height. Once again, I go to the informative brochure, Top Ten Invasive Species, put out by the Beaver Island Association  for their excellent description:

[Marsh Thistle]has a rosette (circle) of leaves at the base that are long, spiny, and deeply lobed. The stem is thick, often reddish, and covered with hairy spines and equally spiny, hairy leaves. The pinkish-purple flowers appear at the top of the stem in a tight cluster, usually in June or July. On Beaver Island this plant is more likely to be found in moist areas than in dry sand.

The brochure goes on to warn that there are some similarities with the native Pitcher’s (beach) thistle, which is a federally threatened (and protected!) species. If in doubt, consult an expert.

The differences between a native plant and an introduced, non-native plant are vast, and have mainly to do with things that keep a plant in check. From things that slow a plant’s growth at a microbial level, to animals that may feed on it, to natural competition for light and nutrients, native species have checks in place. Invasive species do not.

When I spoke at the school, I compared an invasive plant’s advantage to the powers of Superman. If he had chosen to use his powers for evil, rather than for good, we wouldn’t have had a chance against X-ray vision, the ability to fly, super-strength, super-hearing and super-speed.

When invasive plants move in – usually the initial invasion is caused by the activities of man – there is nothing in nature to stop their progress. If left alone, they will forever change the landscape. We have to take control of the problem.

Marsh thistle forms a rosette the first year, and over-winters at ground level.


The next year, it sends up a stalk, flowers, and produces thousands of seeds…which are then dispersed by the wind.


Once introduced, “this plant can aggressively colonize natural areas, decrease biodiversity and compromise the ecological integrity of an area.” (USDA Forest Service)

Let’s not let that happen here!



Continuing the “countdown” of top ten invasive plants here on Beaver Island, let me introduce Spotted Knapweed.

This herbaceous (non-woody) perennial has a unique island story. I made several attempts to have my facts verified and clarified last week, which resulted in only delays. I am betting that – if I get the story wrong – I’ll quickly be given the corrections, so I’m going to tell it as I’ve heard it. Beaver Island is big on nicknames. Over the years we’ve heard names from “Tight” Gallagher to “Killer” Burke to “Red Pup” and “Hannah”.

This invasive plant has a Beaver Island nickname, too. Here, it is often referred to as “Denemy Thistle”. It was unintentionally brought to the island in a load of hay that William “Denemy” Boyle (a relative, by marriage, of “Harlem” Gallagher) shipped over. It came here when agriculture was still an important  industry on Beaver Island, and was noticed right away as an aggressive and unwelcome weed. My grandfather, George Ricksgers, worked very hard to keep it out of his own fields and pastures, and was successful for a while.

Like all invasive plants, the Spotted Knapweed has advantages over native growth. Along with aggressive growth habit, prolific seed production and a long tap root, Spotted Knapweed is phytotoxic, meaning it is poisonous to other plants. That’s quite an advantage, in taking over an area! It thrives in what are called “artificial corridors”: gravel pits, roadsides, field margins, overgrazed pasture land and beaches. It can quickly take over an area, eliminating pasture, native growth and wildlife habitat. On our beaches, it is a big threat to the piping plover.

When pulling this weed, keep in mind that it looks similar, in some stages of it’s growth, to the endangered and federally protected Pitcher’s Thistle, which is an important part of our natural flora. When in doubt, do a bit more research or ask an expert. The other thing to be aware of is that Spotted Knapweed releases an irritant chemical, so gloves should be worn when in contact with it.

If you’d like more information about this, or any of our top 10 invasive species, the brochure put together by the Beaver Island Association is an excellent resource. Copies are available – free – in the lobby of the Community Center.

If you’d like to be involved in group  projects to help control or eradicate invasive plants, please let me know!


Spotted Knapweed in its first year, rosette stage…


…and here, quickly taking over a construction site.

Let’s continue gaining awareness and working together to protect our beautiful island!