Canalside Aquatic Plants

This morning I attended a CIEEM regional field meeting looking at plants alongside (and in) the Stainforth & Kearby Canal at Thorne, South Yorkshire.

It was a relaxed morning, and it was good to see some familiar faces and have a chat. We had a very leisurely stroll down a 600 meter stretch of the canal, sharing knowledge and experience to identify as many plants as we could. Grappling hooks were used to scoop out some of the submerged aquatic vegetation from the canal itself. We also had a look at the coir rolls that were installed and planted up last year to support the bank.

Here are some of the plants found, along with my brief notes on their identifying features:

Submerged Aquatic Plants

- Curly water-thyme (Lagarosiphan major) - leaves curl backwards and are densely spiralled up the stem
- Flowering rush (Butomus umbellatus) - triangular, twisted stem that when snapped apart leaves fibrous strands [photo 1]
- Water-milfoil (Myriophyllum sp.) - slender with feathery leaves
- Yellow water lily (Nuphar lutea) - more obvious venation on leaf
- White water lily (Nymphaea alba) - leaf rounder, flower larger
- Fennel pondweed (Potamogeton pectinatus) - thin grass-like leaves with irregular branching
- Celery-leaved crowfoot (Ranunculus scleratus) - thick stem, shiny three-lobed leaf, yellow flower
- Curled pondweed (Potamogeton crispus) - leaves look crimped rather than curly
- Nuttall's waterweed (Elodea nuttallii) - leaves slightly recurved and taper to a point

Emergent Aquatic Plants

- Arrowhead (Sagittaria sagittifolia) - triangular stem, leaves in three's in a 'wind turbine' shape, flowers and fruit in clusters of three: flowers white with purple centre; fruit spiky like a bur [photo 2]
- Water plantain (Alisma plantago-aquatica) - large, wide, erect leaf with a cordate base
- Narrow leaved water plantain (Alisma lanceolatum) - large, narrow, erect leaf that tapers to the base [photo 3]
- Amphibious bistort (Polygonum amphibium) - creeping habit, pink flowers in a compact spike, floating hairless leaves, rooting from nodes

Wetland/Riverbank Plants

- Marsh woundwort (Stachys palustris) - square stem, leaves short stalked; pink-purple flowers encircling the stem [photo 4]
- Gypsywort (Lycopus europaeus) - square stem; leaves short stalked; many very small white flowers (with purple dots) clustered above leaf axil [photo 5]
- Orange balsam (Impatiens capensis) - oval toothed leaves; orange flower with red-brown spots and a spur that narrows and curves back on itself [photo 6]
- Skullcap (Scutellaria galericulata) - blue-violet flowers with a long calyx tube [photo 7]
- Woody nightshade (Solanum dulcamara) - distinctive purple and yellow flowers; red berries
- Water figwort (Scrophularia auriculata/aquatica) - square stem with wings; leaves oval, opposite and blunt with blunt teeth
- Purple loosestrife (Lythrum salicaria) - tall with red-purple flower spike [photo 8]
- Great willowherb (Epilobium hirsutum) large, downy willowherb with deep pink-purple flowers
- Marsh willowherb (Epilobium palustre) - dainty willowherb with pale pink flowers
- Lesser pond sedge - (Carex acutiformis) - blue-green appearance with rough leaves
- Hemlock water-dropwort (Oenanthe crocata) - poisonous umbellifer
- Horsetail (Equisetum sp.) - distinctive plant - a sample was taken away to try and identify this to species level (either water E. fluviatile or marsh E. palustre)
- Tansy (Tanacetum vulgare) - identified by its distinctive smell, as the plant we found was rather stunted and trodden on, unlike the tall, clumpy yellow-flowered plants I have seen before

It was also good to practice my grasses, with reed canary-grass (Phalaris arundinacea) being identified by it's membranous ligule. (Common reed is larger with a ring of hairs as a ligule). 

Many thanks to Phillippa from the Canal and River Trust for organising the event.