SPIKED WATER-MILFOIL

Myriophyllum spicatum

Water-Milfoil Family [Haloragaceae]

month8jun month8june month8jul month8july month8aug month8sep month8sept

status
statusZnative
flower
flower8yellow
flower
flower8red
petals
petalsZ4
type
typeZspiked
type
typeZtieredwhorls
stem
stem8round
sex
sexZbisexual
sex
sexZmale
sex
sexZfemale

11th Aug 2018, in canal, Leeds & L/pool, Maghull, Merseyside Photo: © RWD
The leaves and the rest of the stems which are up to 2.5m long are submerged; only the much shorter flowering spikes poke their heads above water. It is possible a passing canal boat has chopped the stems off below water-level, for they are lying horizontal on or near the waters surface. The submerged pale-green patch beneath the 'flowers' are the leaves, which are feathered and in whorls of 4 around the submerged stem at intervals and perhaps also a green algae of somesort. [The rest are other weeds of water]


11th Aug 2018, in canal, Leeds & L/pool, Maghull, Merseyside Photo: © RWD
These tiny red ovals on the stems above water are not the flowers per se, but rather their fruits; the flowering season is a bit earlier in June.


11th Aug 2018, in canal, Leeds & L/pool, Maghull, Merseyside Photo: © RWD
The red fruiits are in tiny whorls up the above-water stems. The flowers/fruits are in leafless spikes. The stems of Spiked Water-milfoil have a distinctive reddish tinge.


11th Aug 2018, in canal, Leeds & L/pool, Maghull, Merseyside Photo: © RWD
The browner fruits are more mature. [The tiny white flowers on much thinner stalks are of a differing water-plant: those of one of the Elodea species of Waterweeds]. [The bubbles are a result of photosynthesis taking place under the water].


11th Aug 2018, in canal, Leeds & L/pool, Maghull, Merseyside Photo: © RWD
Here is a fruiting spike which escaped into your Authors hands. The smaller green ones on the lower parts are yet to mature and turn red. Some still seem to have the translucent white stigmas attached at the top. Both male-only flowers and female-only flowers occupy the stems. Occasionally the flowers are bisexual.

The flowering stems are rather rigid and do not flop over when removed from the water.



11th Aug 2018, in canal, Leeds & L/pool, Maghull, Merseyside Photo: © RWD
Green bracts shorter than the flowers hold the flowers (in this case fruits) in place. [Green 'strings' of some water weeds entwine it in an embrace]. The fruits are in whorls of 4 around the stem; here bunched into 3 overlapping whorls of 4 (the fruits are larger in comparison to the flowers).


11th Aug 2018, in canal, Leeds & L/pool, Maghull, Merseyside Photo: © RWD
There is a whitish 'X' at the top of the red fruits.


11th Aug 2018, in canal, Leeds & L/pool, Maghull, Merseyside Photo: © RWD
Barely visible below the water-line, all leaves are submerged. The leaves have a circular cross section and wire-like, with branches either side, in whorls of (usually) 4 at intervals around the stem.


11th Aug 2018, in canal, Leeds & L/pool, Maghull, Merseyside Photo: © RWD


11th Aug 2018, in canal, Leeds & L/pool, Maghull, Merseyside Photo: © RWD
Here you can make out 3 leaves with curving side-branches but the fact that each is in a whorl of 4 is not apparent through the murky water (and the high zoom-level of the image - these plants were nowhere near the waters' edge).


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].

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

Uniquely identifiable characteristics

Distinguishing Features : see photo captions

Both male-only flowers and female-only flowers occur in whorls around the top part of the stems which are above the waterline. Occasionally the flowers are bisexual with both anthers and styles. The anthers of male flowers are cream-coloured and stick out from the bracts. The styles of female flowers are brown and stubby atop a short greenish barrel-shaped structure whilst those of male flowers have 4 curled-over white petals with long green to yellow stamens and are twice to 3 times as long as the female flowers. Both male, female and bisexual flowers occur in whorls of 4 around the stem. Photos required of the male, female and bisexual flowers...

The leaves are between 0.5 to 1.5 times as long as are the gaps between the whorls on the stem and each has between 13 to 35 segments (whereas those of Whorled Water-Milfoil are between 1.5 to 4 times longer than the (shorter) internodes between whorls, 25 to 35 segments). The flower spike of Spike Water-milfoils do not collapse when removed from the water (whereas those of Whorled Water-Milfoil do).

It is native and grows mostly in basic waters in ponds, ditches, lakes, slow streams and slow rivers and in canals, mostly in the lowlands widespread throughout the British Isles but becoming scarcer in the North and West. It can also tolerate eutrophic (rich in minerals) or slightly salty (brackish) water.


  Myriophyllum spicatum  ⇐ Global Aspect ⇒ Haloragaceae  

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

SPIKED WATER-MILFOIL

Myriophyllum spicatum

Water-Milfoil Family [Haloragaceae]