ALTERNATE WATER-MILFOIL

ALTERNATE-LEAVED WATER-MILFOIL

Myriophyllum alterniflorum

Water-Milfoil Family [Haloragaceae]

month8may month8jun month8june month8jul month8july month8aug

status
statusZnative
flower
flower8yellow
morph
morph8actino
petals
petalsZ4
type
typeZspiked
stem
stem8round
sex
sexZbisexual
sex
sexZmale
sex
sexZfemale

30th Aug 2010, MB&BC canal, Radcliffe, Lancs. Photo: © RWD
Frogbit top LH corner. This is has the shortest main stem of any Myriophyllem (aka Water-milfoils), being up to 1.2 m in length. Unsure what the lighter-coloured stuff floating on the surface is. Alternate Water-Milfoil centre-stage, and floating on and just below the surface. The spikes droop downwards at first then upright when in flower (with male, female and bisexual flowers in the flower spike).


30th Aug 2010, MB&BC canal, Radcliffe, Lancs. Photo: © RWD
[The pale green things are of some other plant, possibly the fruits or leaves from a nearby shrub or tree]


30th Aug 2010, MB&BC canal, Radcliffe, Lancs. Photo: © RWD
Unlike the other Water-milfoils, this one has long leaves with numerous whorls - which branch off a main stem alternately, hence the common name.


30th Aug 2010, MB&BC canal, Radcliffe, Lancs. Photo: © RWD
The leaves are in whorls of 4 (sometimes in whorls of 3).


30th Aug 2010, MB&BC canal, Radcliffe, Lancs. Photo: © RWD


30th Aug 2010, MB&BC canal, Radcliffe, Lancs. Photo: © RWD


30th Aug 2010, MB&BC canal, Radcliffe, Lancs. Photo: © RWD
Each leaf has between 6 to 18 segments (far fewer than the 8 to 30 of the non-native Parrot's Feather, the 24 to 35 segments of Whorled Water-Milfoil or of the 13-38 segments of Spiked Water-Milfoil)


unknown date, unknown place, IOW. Photo: (CC by 2.0) Geoff Toone
Dried specimens - this one younger and still green(ish).
unknown date, unknown place, IOW. Photo: (CC by 2.0) Geoff Toone


unknown date, unknown place, IOW. Photo: (CC by 2.0) Geoff Toone
Dried specimens - this one younger and still green(ish).


unknown date, unknown place, IOW. Photo: (CC by 2.0) Geoff Toone


unknown date, unknown place, IOW. Photo: (CC by 2.0) Geoff Toone


Not to be semantically confused with : Marsh Cinquefoil (Comarum palustre), Hop Trefoil (Trifolium campestre), Yellow Milfoil (Achillea tomentosa) nor Trefoil Cress (Cardamine trifolia) [plants with similar names belonging to differing families].

Uniquely identifiable characteristics

Distinguishing Feature : See photo captions

No relation to : Flower [a plant with similar name].

The name 'alternate' refers not to the leaflets which look similar to those of Whorled Water-Milfoil but to the alternate branching of the stems which is clearly depicted in the above photographs.

Many similarities to : other Milfoils such as Spiked Water-Milfoil (Myriophyllum spicatum), Parrot's Feather (Myriophyllum aquaticum), Two-leaf Water-milfoil (Myriophyllum heterophyllum), Red Water-milfoil (Myriophyllum verrucosum) nor with Whorled Water-Milfoil (Myriophyllum verticillatum),

It apparently grows in lakes, ponds, streams, dykes, preferring acidic waters (such as peaty water as found up to 780m high on your Authors bog walks in the Dark Peaks - except he hasn't noticed any there as your Author tries to avoid sinking in deep wet peat). Most often found in the North and West.

Photos of flowers, both male and female required.


  Myriophyllum alterniflorum  ⇐ Global Aspect ⇒ Haloragaceae  

Distribution
 family8Water-Milfoil family8Haloragaceae
 BSBI maps
genus8Myriophyllum
Myriophyllum
(Water-Milfoils)

ALTERNATE WATER-MILFOIL

ALTERNATE-LEAVED WATER-MILFOIL

Myriophyllum alterniflorum

Water-Milfoil Family [Haloragaceae]