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Fireweed vs. Loosestrife

It’s great to see people becoming increasingly aware of PEI’s invasive species. Unfortunately, I’m seeing more and more cases of people confusing beneficial native species with problematic invasives. Recent examples include mistaking Cow Parsnip for Giant Hogweed, Eye-spotted Lady Beetles for Asian Lady Beetles, and Fireweed for Purple Loosestrife. The native Fireweed (Chamaenerion angustifolium) and invasive Purple Loosestrife (Lythrum salicaria) are both are flowering now, so let’s take a look.

Fireweed (left) is a member of the Evening Primrose Family (Onagraceae), and its favourite number is four. Each flower has four bright pink petals that alternate with four smaller, slightly darker sepals (they protected the flower when it was in bud). The stigma – the female part of the flower that receives pollen – is long and gracefully divided into four parts. (It’s that long white thing in the centre of the flowers in the photo). The overall flower head is loose-looking and pyramid-shaped.

Purple Loosestrife (right) is a member of the Loosestrife Family (Lythraceae). Its flowers are a darker shade than Fireweed, have five or six petals rather than four, and lack that long central stigma. The flower head is cylindrical and more compact than Fireweed. Flower heads of Fireweed and Loosestrife are sufficiently different that you can tell them apart from a long way off or while driving at highway speed.

The stems and leaves of these plants are also very different. Purple Loosestrife stems are square, while those of Fireweed are round. Fireweed leaves are long and alternate, compared to the short, opposite (or sometimes whorled) arrangement in Purple Loosestrife. If your plant has a round stem with only a single leaf at any one point, that’s Fireweed. If it has a square stem with two or more leaves at any one point, that’s Purple Loosestrife.

It’s a useful difference to know. All parts of Fireweed are edible. In spring, young shoots and leaves can be eaten raw or cooked. Later, leaves can be fermented to make a caffeine-free black tea. Flowers can be eaten raw or cooked into a syrup or jelly. Inside the stem is pith, which has a slightly sweet taste; it can be eaten as a trailside snack or added to soups and other dishes as a thickener. Roots can be roasted and eaten. Finally, when Fireweed goes to seed it produces a cottony fluff that can be used as a fire starter, stuffing, or woven into textile.

Removing invasive species is a great way to help the local environment, but please ensure what you have is indeed invasive rather than native. The PEI Invasive Species Council is a great source of information, and you can find them on Facebook or via their website.

Invasive species are unwelcome, but our native species are all important parts of PEI untamed!

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