29
THE FLORA
Although some 82 higher plants and a fern were recorded on
the trip - fortuitously the same number as in 1891, many
of them were wayside species. The list below is therefore
restricted to those plants actually in the canal or at its
edges.
Acorus calamus
Alisma plantago-aquatica
Alnus glutinosa
Angelica sylvestris
Apium nodiflorum
Bidens tripartita
Brassica nigra
Butomus umbellatus
Carex riparia
Ceratophyllum demersum
Conium maculatum
Elodea nuttallii
Epilobium hirsutum
Eupatorium cannabinum
Filipendula ulmaria
Glyceria maxima
Iris pseudacorus
Juncus effusus
J. inflexus
Lemna gibba
L. minor
Lycopus europaeus
Lythrum salicaria
Mentha aquatica
Myosotis palustris
Myosoton aquaticum
Myriophyllum spicatum
Nuphar lutea
Nymphaea alba
Phalaris arundinacea
Phragmites communis
Polygonum amphibium
P. cuspidatum
Potamogeton lucens
P. pectinatus
Potamogeton perfoliatus
Ranunculus sceleratus
Rorippa amphibia
Rorippa nasturtium-aquaticum
Rumex hydrolapathum
Sagittaria sagittifolia
Salix fragilis
S. viminalis
Schoenoplectus lacustris
Scrophularia aquatica,
Scutellaria galericulata
Solanum dulcamara
Sonchus arvensis
Sparganium ereatum
Stachys palustris
Symphytum officinale
Typha angustifolia
T. latifolia
Veronica beccabunga
The first observation of interest was the abundance of the -
fat duckweed, Lemna gibba, in all the locks. As the gates
closed and each lock began to fill with water the duckweed
was concentrated until it carpeted the lock from side to
side. Possibly it is more tolerant of the oil pollution and
enhanced nutrient status of the present day canal, as it