A Beautiful Invasive at Touraine Marsh, Gatineau: August 2020

It was a surprise to find this lovely marsh in the City of Gatineau Quebec so near to a highway and housing developments.

hill that you are forbidden to slide down

Flowering-rush is a perennial aquatic invader from Eurasia that resembles a large sedge, and flourishes along shorelines and as a submersed plant in lakes and rivers.

Flowering-rush (Butomus umbellatus)

Dense stands interfere with recreation, crowd out native plants, and can be harmful to fish and wildlife.

Flowering-rush (Butomus umbellatus)

Flowering rush is regarded as one of five invasive alien plants (along with garlic mustard, dog-strangling vine, Japanese knotweed and phragmites) having a major ecological impact on natural ecosystems in Canada, and is considered a high priority species for eradication in parts of Ontario, mainly the Great Lakes. 

Flowering-rush (Butomus umbellatus)

If flowering rush establishes in a lake, its growth varies due to changes in seasonal weather and annual changes in temperature and water clarity. A change in water level can allow this plant to easily invade newly exposed areas. Once established, flowering rush can displace native vegetation, reducing the overall biological diversity of an ecosystem.

Flowering-rush (Butomus umbellatus)

Looking on the bright side, it has gorgeous flowers!

Flowering-rush (Butomus umbellatus)

Other botany:

Swamp Buttercup (Ranunculus hispidus)
Spikenard (Aralia racemosa)
Spikenard (Aralia racemosa)
Boneset (Eupatorium perfoliatum)
Calico Aster (Symphyotrichum lateriflorum)
Large-leaved Aster (Eurybia macrophylla)
Amur Maple (Acer maackii)
Chicory (Cichorium intybus)
Staghorn Sumac (Rhus typhina)
Cow-parsnip (Heracleum maximum)
Doll’s-eyes (Actaea pachypoda)
Butterfly Pea (Clitoria mariana)
Butterfly Pea (Clitoria mariana)
Joe-pye-weed (Eutrochium maculatum)
Spotted Jewelweed (Impatiens capensis)
White Sweet-clover (Melilotus alba)
Mugwort (Artemisia vulgaris)
Red-osier (Cornus sericea)
Spiny-leaved Sow Thistle (Sonchus asper)
Spiny-leaved Sow Thistle (Sonchus asper)
Glossy Buckthorn (Rhamnus utilis)
Blackberry (Rubus)
Blackberry (Rubus)
Partridge Berry (Mitchella repens)
Starry False Solomon-seal (Maianthemum stellatum)
Canada Goldenrod (Solidago canadensis)
Purple-flowering Raspberry (Rubus odoratus)
Purple-flowering Raspberry (Rubus odoratus)
Birdfoot Trefoil (Lotus corniculatis)
Prickly Lettuce (Lactuca serriola)
Green Foxtail (Setaria viridis)
Green Foxtail (Setaria viridis)
Hop-hornbeam (Ostrya virginiana)
Coltsfoot (Tussilago farfara)
Crown Vetch (Securigera varia)
Crown Vetch (Securigera varia)
Tartarian Honeysuckle (Lonicera tatarica)
Bladder Campion (Silene vulgaris)
Mullein (Verbascum thapsis)
Smooth Crabgrass (Digitaria ischaemum)
Hoary Alyssum (Berteroa incana)

Some insects:

Asian Beetle
Red-legged Grasshopper and Asian Beetles
Red-legged Grasshopper
Northern Paper Wasp

Thanks to Ken Sproule for assistance in insect identification.


August brings the sheaves of corn,
Then the harvest home is borne.     – Sara Coleridge (1802–52) 

Miles Hearn

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