Presentation on theme: "Aquatic macrophytes can be considered good biological indicators of pollution because: they are sensitive to pesticides, to organic pollution and to eutrophication."— Presentation transcript:
Aquatic macrophytes can be considered good biological indicators of pollution because: they are sensitive to pesticides, to organic pollution and to eutrophication They are easy to identify They aren’t movable This index is based on the presence/absence of some taxa belonging to different groups of sensibility We can define four groups ( A-B-C-D-) with a gradient of decreasing sensibility M I S Macrophyte Index Scheme (Wegher e Turin, 1987)
RANUNCULUS SP Scientific name: Ranunculus Sp. Common name: Buttercup, Golden Button Family: Ranuncolcee Characteristics: A vigorous, herbaceous plant, that grows in normal or marshy land and spontaneously in Italy. Buttercups originally had simple flowers with five petals but today there are hybrids with semi-double or double flowers Colour of flowers: Buttercup flowers may be yellow, white, orange, red or tobacco; they are characterized of brilliant tones and of a particular shininess.
RANUNCULUS SP Period of flowering: This varies depending on the species and the altitude. Some buttercups announce spring, others flower in summer. Reproduction: The buttercup plant can be reproduced by dividing the tuberous roots or by sowing seeds but the latter way is extremely difficult. In Italy there are about fifty wild species of buttercups, a plant with fleshy roots, known as “feet” that are similar to tubers and leaves that are different depending on the species, ranging from divided or whole, linear or palmate shape. Buttercups prefer open but sheltered places with sunlight in the warmer hours of the day.
CALLITRICHE spp Water-starworts are small, delicate plants usually found in shallow water. All species are loosely rooted to the bottom with narrow underwater leaves and/or broadened floating leaves arranged in pairs along thin stems. Characteristics of water-starworts are quite variable and depend on growing conditions. To be sure of their identification to species, the surfaces of mature fruit need to be examined under 10-20x magnification.
CALLITRICHE HAMULATA Scientific name: CALLITRICHE HAMULATA Common name: Intermediate Water- Starwort Description: the stem is thin and it can grow till 30-40 cm of length. Young leaves are submersed, long and thin; their colour is light green. Meanwhile the plant grows up its leaves become wider and oval. The leaves that can reach the surface are round and form a kind of “star” floating on the water surface.Flowers are small, green, without petals; they flower between April and September, but it’s difficult to see them because of their small size. Habitat: the callitriche grows in clean waters with a slow flow; it is typical of a spring river.
RANUNCULUS AQUATILIS White water-buttercup is found in ponds, lakes, ditches and streams. The small white flowers with a yellow centre rise above the water surface. Many white water- buttercup plants have two distinct types of leaves: very finely divided, thread-like, fan-shaped underwater leaves, and floating or emersed leaves that appear scalloped. Often only the underwater leaves are present. The plants sometimes form conspicuous mats on the water surface.
RANUNCULUS AQUATILIS Leaf: The leaf form is variable depending on the season and growing conditions, but the leaves are always alternately arranged on the stem. Submersed leaves are branched into more than 20 thread-like segments. These fan-shaped leaves are 1-4 cm wide and are attached to the stem by 1-2 cm long leaf stalks. Floating leaves: are often absent. When present, these scalloped leaves (0.5-2 cm long) are flat and have 3 to 5 main lobes. Stem: The long smooth or slightly hairy stem can grow up to 1 m and it is weak, branched, and rooting at the lower nodes.
RANUNCULUS AQUATILIS Flower: Single flowers on stalks (1-6 cm long) rise above the water surface. Each flower is 1-2 cm across, has a yellow centre, and 5 white petals. As the fruit matures, the petals detach and the flower stalks tend to curve away from the stem. Fruit: White water-buttercup has clusters of 10 to 50 achenes per flower. Each achene is 1.5 -2.5 mm long, has a pointed end, and often has cross ridges. Root: Fibrous roots often emerge from nodes on the lower portions of the stems. Propagation: Seeds and stem fragments. Habitat: Ponds, lake margins, rivers, slow- moving streams or ditches.
RANUNCULUS PELTATUS R. peltatus is generally found in slow- moving streams or in lakes or ponds. It requires fairly nutrient-rich (eutrophic) conditions. Often it will form dense and very conspicuous beds Flowers are white (or very pale pink), somewhat larger than all other water- crowfoots. Leaves are either finely dissected if submerged, or round and lobed. Individual plants will normally carry both kinds of leaf at time of flowering (from May to August).
CALLITRICHE STAGNALIS Pond water-starwort usually has spoon-shaped floating leaves crowded at the stem-tip. Leaf: Opposite. Narrow submersed leaves (up to 10 mm wide) with one rounded leaf tip are sometimes present. Oval or spoon-shaped floating leaves are up to 10 mm wide and are joined by tiny ridges at the base. Stem: Usually branched, rising to surface or sprawling. Flower: Tiny flowers lack sepals and petals and are located at the leaf bases on minute stalks. 2-4 tiny whitish bracts emerge from the flower base. Fruit: Small, located at the leaf bases. Four compartments, each containing one seed. Oval, 1.2- 1.8 mm long, 1.2-1.7 mm wide, narrow margin all around (wing); bracts at base. Root: Fibrous, from plant base or sprouting from stem joints. Propagation: Plant fragments, seeds. Habitat: Shallow water of lake margins and streams.
CALLITRICHE OBTUSANGULA English name:Blue-fruited Water-starwort Scientific name: Callitriche obtusangula Le Gall Diagnostic features: Aquatic perennial, but not fruiting if submerged. Submerged leaves: linear. Floating leaf-blades: broadly rhombic, each vein usually marked by a fine raised ridge when fresh. Stamens: c.5mm; anthers c.0.6mm wide. Pollen grains: markedly ellipsoid or slightly curved. Fruits: c.1.5 x 1.2mm, unwinged, with ± erect styles. Habitat: Native; in and by ponds and streams.
CALLITRICHE PLATYCARPA English name Various-leaved Water- starwort Scientific name: Callitriche platycarpa. It forms rosettes with 10-12 leaves, the single leaves in the rosette are like the submerged leaves, eliptic or narrow spatulate, while the emerse leaves are more broad. The plant name: The genus-name Callitriche comes from the greek words kalos (= beautifull) and thrix (= hair), the name refer to the smallness of the genus, the species- name platycarpa is likewise greek and comes from platys (= flat) and karpon (= fruit).its are brown with thigh ali. It grows in poor (of minerals) waters.
CHARA SPP. Species: Chara spp., English name:muskgrass, stonewort, muskwort Although these common lake inhabitants look similar to many underwater plants, they are actually algae. Muskgrasses are green or grey- green coloured algae that grow completely submersed in shallow (4 cm) to deep (20 m) water. Individuals can vary greatly in size, ranging from 5 cm to 1 m in length. The main "stem" of muskgrasses bear whorls of branch lets, clustered at regularly spaced joints. When growing in hard water, muskgrasses sometimes become coated with lime, giving them a rough gritty feel. These algae are identifiable by their strong skunk-like or garlic smell, especially evident when crushed.
FONTINALIS ANTIPYRETICA Species: Fontinalis antipyretica Hedw, English name: common water moss Family:Fontinalaceae Common water moss is a dark green underwater plant that attaches to rocks or logs in flowing water, or floats loose or attached in still water. The leaves are sharply pointed, ridged, overlapping, and arranged in 3 rows along the entire length of the stems. The stems grow up to 60 cm long and appear triangular if the leaves are removed. Common water moss does not produce flowers, reproducing by stolons, plant fragments, or spores instead. It is often found dried and dormant above water in the summer.
FONTINALIS ANTIPYRETICA Leaf: The rather rigid, sharply-pointed leaves are 4 to 9 mm long, broadly lance- shaped to egg-shaped, and have a lengthwise ridge down the back. They are arranged in 3 rows and partly overlap along the entire length of the stem. When removed from the stem, the leaves appear to be folded length-wise down the middle. Stem: The branching stem is 20 to 60 mm long, conspicuously three-angled (appears triangular in cross section), and entirely covered by the leaves. Flower: None, produces spores instead. Fruit: Microscopic spores are produced in smooth capsules that measure 2 to 2.6 mm long. Spores are only produced on plants that are subjected to periods of drying. Fertilization and spore release will only take place above water. Root: No true roots. Rootlets (rhizoids) attach common water moss to rocks and logs.
FONTINALIS ANTIPYRETICA Propagation: Mostly by stolons and leafy plant fragments. Infrequently by spores. Habitat: Water moss is found attached to rocks or logs in swift flowing water, or floating loose or attached to substrate in still water. It is common in shaded sites and prefers slightly acidic water. It requires water below pH 8.4 where dissolved carbon dioxide is available. It is characteristic of cold flowing waters. It is constitute by small stems (long 30-50 cm) tag at the bottom. It grows in environments with temperatures between 10°C and 15°C, clean water with neutral pH and media durezza.
POTAMOGETON LUCENS Leaves of only one kind, not separated into submerged and floating. Leaves on main stem 7-20 cm long. In the axil of each leaf is a stiff, pale green, yellowish or reddish stipule, about 40% as long as the leaf, with two conspicuous ribs or keels. All leaves have a short stalk about 1-12 mm long. Other features: Leaves wavy- edged. On either side of the midrib there are about 2 prominent veins and outside those another 2 or so fainter ones. Joining these lengthwise veins there are thinner but still very conspicuous cross-veins, which are at an angle of about 60-80° to the main veins, both near the midrib and near the edge. Fruit-spike thickening upwards.
POTAMOGETON OBTUSIFOLIUS Family: Potamogetonaceae Duration : Perennial Rhizomes absent. Cauline stems slightly compressed, without spots, 35-90 cm; glands yellow-green to gold, 0.2-1 mm diameter. Turions terminal, abundant, soft; outer leaves 3-4 per side, base not corrugate, apex apiculate to obtuse; inner leaves undifferentiated. Leaves submersed, ± spirally arranged, sessile, flaccid; stipules persistent, inconspicuous, convolute, free from blade, white, not ligulate, 0.6-1.8 cm, fibrous, rarely shredding at tip, apex obtuse; blade light green to somewhat reddish, linear, not arcuate, base slightly tapering, without basal lobes, not clasping, margins entire, not crispate, apex not hoodlike, obtuse or round-apiculate, lacunae in 1-3 rows each side of midrib; veins 3. Inflorescences unbranched, emersed; peduncles not dimorphic, axillary, erect, rarely recurved, cylindric; spike not dimorphic, cylindric, 8-13 mm. Fruits sessile, olive-green to brown, obovoid, turgid, abaxially keeled or not, laterally keeled or not, lateral keels when present without points; sides without basal tubercles; embryo with 1 full spiral. Flowering and fruiting summer fall. Medium- to low- alkaline waters of lakes and slow-flowing streams; It has two hybrids, Potamogeton obtusifolius P. pusillus and P. friesii obtusifolius.
ELODEA CANADENSIS These underwater perennial plants sometimes occur as tangled masses in lakes, ponds, and ditches. Individual plants within each species vary in appearance depending on growing conditions. Some are bushy and robust, others have few leaves and weak stems. Both have long, trailing stems with green, somewhat translucent leaves arranged in whorls of 3 around the stem.
ELODEA CANADENSIS Leaf: Mostly arranged in whorls of 3 (occasionally 4), but sometimes opposite on the lower portions of the stems. Leaves very finely toothed along the edges, but evident only with magnification. Stem: Long, slender, generally branched. Common waterweed is more sparingly branched than Nuttall's waterweed. Flower: Often does not produce flowers. Small (8 mm across), white flowers occur at the ends of long, thread-like stalks and have 3 petals and usually 3 sepals. Male and female flowers occur on separate plants, but male flowers are rarely produced. Blooms from July to September. Fruit: Capsules approximately 6 mm long, seeds about 4 mm long, but because of a shortage of male plants, seeds are seldom produced. Root: Tufts of fibrous roots from nodes along the stem. Propagation: Stem fragments, over wintering buds, and rarely by seeds. Habitat: Lakes, rivers, ponds and ditches.
HIPPURIS VULGARIS Species: Hippuris vulgaris Family: Hippuridaceae Common mare's-tail looks like a robust green bottlebrush growing in patches primarily in the shallow areas of streams, ponds, and lakes or on wet muddy shores when water levels drop. This plant is characterized by unbranched stems, abundant whorled leaves, and inconspicuous flowers. The leaves and stems vary in form depending on whether they are growing underwater or are emergent. The underwater plant portions are limp, flexible, and have very long leaves. Emergent portions are stiff and erect, with short narrow leaves.
HIPPURIS VULGARIS Leaf: Arranged in whorls; 6-12 stalk less, smooth-edged leaves per whorl. Two types: submersed leaves are soft, pale green, and measure up to 5 cm long and 3 mm wide. Emergent leaves are dark green, stiffer, and smaller. In deeper water only the submersed leaf form may be present. Stem: The unbranched stem is hollow, up to 1 m long, and forms roots at the nodes. The stem is erect when emergent; limp when submersed; and can form creeping rhizomes.
HIPPURIS VULGARIS Flower: Small, inconspicuous flowers are located at the leaf bases. The flowers which lack petals and sepals, are reduced to a tiny rim. Fruit: Tiny (mature fruit about 2 mm long), nut-like, located at leaf bases. Root: Fibrous. Arising from lower portion of stems and rhizomes. Propagation: Seeds, rhizomes. Will re- grow from stem cuttings. Habitat: At the edges of lakes, ponds, and streams in fresh, usually shallow water, though it will grow in water up to 2 m deep.
APIUM NODIFLORUM Family: Apiaceae Type: glaborous, perennial. Hel. Taste: nauseous. Stems: procumbent or ascending, rooting at lower nodes, flring stems rooting at base, hollow, finely grooved. Height: 30-100cm Umbels: compound, sessile or shortly procumbent. 3-15, 1-2 cm rays, subequal, scabrid, spreading or recurved (0.3) 1-2 cm. Peduncles < than rays; or almost absent, leaf opposed.
APIUM NODIFLORUM Leaves: simply pinnate, bright green, shiny. 2- 4 (6) pairs of lobes, 1.5-6 (10) cm, lanceolate to ovate, serrate or crenate somewhat lobed, sessile. Cotyledons contracted into petiole. Bracts: absent. Bracteoles 4-7, linear lancolate to ovate, = or > than flowers. Flowers: greenish white. Styles form a stylopodium. Fl.7-8. Fuit: 2-2.5 mm ovoid, laterally compressed, smooth. Commisure narrow. Mericarps with prominent thick ribs. Carpophore present. Vittae solitary. Pedicels 1-2 mm. Styles > than stylopodium, recurved, stigma a small knob. Habitat: ditches, shallow ponds, wet places. Nutrient rich calcerous soil.
RORIPPA NASTURIUM-AQUATICUM This emergent perennial herb is typically observed as a tangle of stems and leaves growing in cold, flowing water. Usually the ends of the stems and the leaves are held above the water. The leaves are compound, each consisting of a central stalk with several round leaflets that have smooth or slightly wavy edges. The leaves have a strong peppery taste. The small flowers each have 4 white petals and are clustered at the ends of the stems. Leaf: The older leaves are compound, with each leaf consisting of 3 to 11 smooth or wavy-edged, oval or lance-shaped leaflets growing from a central stalk. The entire leaf measures 4 to 12 cm long, with the end leaflet usually larger than the others. Young leaves are simple, not compound. Stem: The trailing, fleshy stem is 10-60 cm long, breaks easily, and is upright at the ends. It forms roots at the lower nodes. Flower: White flowers appear above the water from March through October. The flowers are clustered at the ends of the stems on short stalks. The flowers are 3-5 mm long and have 4 white petals. Fruit: Thin, slightly curved, cylindrical pods are 10-25 mm long and about 2 mm wide, on stalks 8-12 mm long. The seeds are small (1 mm), round, and arranged in four rows inside the pods.
RORIPPA NASTURIUM-AQUATICUM Root: Thin and fibrous. Roots often grow from the nodes of the trailing stems. Propagation: Rooting stem fragments and seeds. Habitat: Flowing streams and other shallow fresh water; prefers cold moving water. Flower: White flowers appear above the water from March through October. The flowers are clustered at the ends of the stems on short stalks. The flowers are 3-5 mm long and have 4 white petals. Fruit: Thin, slightly curved, cylindrical pods are 10-25 mm long and about 2 mm wide, on stalks 8-12 mm long. The seeds are small (1 mm), round, and arranged in four rows inside the pods. Root: Thin and fibrous. Roots often grow from the nodes of the trailing stems. Propagation: Rooting stem fragments and seeds. Habitat: Flowing streams and other shallow fresh water; prefers cold moving water.
Zannichellia palustris Sparganium spp. Callitriche hermaphroditica Potamogeton crispus Potamogeton natans Potamogeton perfoliatus Nuphar lutea Lemna minor Lemna trisulca Enteromorpha sp. Scirpus lacustris Myriophyllum spicatum GROUP C
ZANNICHELLIA PALUSTRIS Family: Zannichelliaceae Scientific name: Zannichellia palustris L. English name:Horned Pondweed Horned pondweed is a delicate underwater branching perennial that can grow to a length of 1 m. It has opposite, thread-like leaves that emerge in such a way as to give the plants a uniform shape. Unlike many look alike aquatic plants which have flowers that emerge from the water on spikes, horned pondweed has inconspicuous underwater flowers and fruits located at the leaf bases. Look for this plant in brackish or alkaline streams, ponds, ditches, and lakes.
SPARGANIUM SPP English name:Branched Bur-reed Botanic notes: monocotyledonous and perennial plant, rhizomatous root. Land of bloom: humid places and ditches. Description: A very common plant of wet ditches, channels, fens, lake- sides, river-sides, ponds and similar wet habitats. Easily recognised, with its tall shoots reaching four feet or so, long, narrow keeled leaves, and a stem which carries a branched inflorescence of globular heads of male and female flowers. The female flowers develop into a bur-like structure which eventually breaks up into its separate fruits for dispersal.
CALLITRICHE ERMAPHRODITICA Autumnal Water-starwort Scientific name: Callitriche hermaphroditica L. Diagnostic features Submerged annual to 50cm. Leaves 8-18mm, widest near base, tapering to emarginate apex, usually pale to mid green. Fruits common, ± orbicular in side view, c.1.4-2.2(3.3)mm, with wing 0.1- 0.5mm wide. Chromosome number: 2n=6. Habitat: Native; lakes and rivers.
Curly leaf pondweed grows entirely underwater except for the flower stalk which rises above the water. Curly leaf pondweed has distinctly wavy-edged, crispy olive-green to reddish-brown leaves. It usually grows early in spring and dies back in summer. The leaves of flat-stem pondweed are long and narrow with smooth edges and the sharp-edged stem is flat. POTAMOGETON CRISPUS
Leaf: Alternate, all submersed, no leaf stalks. Oblong, stiff, translucent leaves (4-10 cm long, 5-10 mm wide) have distinctly wavy edges with fine teeth and 3 main veins. Sheaths (stipules) up to 1 cm long are free of the leaf base and disintegrate with age Stem: branched, up to 90 cm long, somewhat flattened. Flower: Tiny, with 4 petal-like lobes, in spikes 1-3 cm long on stalks up to 7 cm long. Fruit: Seed-like achene, 4-6 mm long including 2-3 mm beak, back ridged. POTAMOGETON CRISPUS
Root: Fibrous, from slender rhizomes. Propagation: Seeds and creeping rhizomes, over- winters as a hard, brown, bur-like bud with crowded, small holly-like leaves. Distribution: nearly worldwide Habitat: shallow to deep still or flowing water, tolerant of disturbance. Life history of Potamogeton crispus is unusual as it flowers and fruits in late spring and early summer, at which time it also produces turions. The plants decay shortly after those structures develop, leaving only fruits and turions, which survive the summer. No one has observed any seed germination, but the turions (referred to as dormant apices) germinate in late summer or fall, and the plants overwinter as small plants only a few cm centimetres in size, even under the ice in northern climates (R. L. Stuckey et al. 1978). Growth then continues as the water begins warming in the spring. POTAMOGETON CRISPUS
This perennial pondweed have oval floating leaves and long, narrow, underwater leaves. The underwater leaves have a broad light green central stripe, the floating leaves are often oppositely arranged. The underwater leaves are so narrow that they appear to be stiff leafless stalks, and the floating leaves often have slightly heart- shaped bases. POTAMOGETON NATANS
Submersed leaves: They are alternate and stiff and can be until 50 cm long and up to 2 mm wide. Floating leaves: They are alternate and have a colour variable from dark green to copper-coloured; they can be from 6 to 11 cm long and they have a width of 6 cm. their base is heart- shaped and the stalk is longer than the leaf blade. Persistent sheaths (stipules): they can be from 6 to 8 cm long and are free from the leaf base Stem: It is generally unbranched and nearly cylindrical. It is 2 mm thick.
Flower: It consists of compact spikes less than 5 cm long on stalks with a length of 12 cm. Fruit: It is from 3.5 to 5 mm long; the back is rounded or faintly ridged with a beak of 0.5-1 mm. Root: It is fibrous and composed by rhizomes. Propagation: It happens through seeds come by large winter buds. These plants sometimes produce tubers. POTAMOGETON NATANS
POTAMOGETON PERFOLIATUS Family: potamogetonaceae Perfoliate Pondweed Potamogeton perfoliatus is a submerged aquatic plant that occurs in still and flowing freshwaters in temperate climates. It is known as clasped pondweed as the leaf bases perfoliate (are wrapped around the stem). This is one of the commonest pondweeds. All the leaves are under water; there are no floating leaves as in some other common Potamogeton species. It is common in lakes, ditches and slow rivers and streams, and is tolerant of quite a wide range of nutrient status.
POTAMOGETON PERFOLIATUS Description: P. perfoliatus is one of the common pondweeds, rather robust, with the leaf bases wrapped around the stem. All the leaves grow under water and there are no floating leaves. Leaves are flat, oval- shaped, 2-6 cm long, narrow (due to lack of light and calcium) but margins are slightly crisped. Plants have thicker, darker green foliage than do plants growing in deeper water (MDNR, 2005). Ailstock and Shafer (2004) state “reedgrass typically survives in winter by persistence of sparsely branched pale rhizomes embedded in the sediments. Inflorescences are variable but mostly consisting of 5-12 flowers with each consisting of 4 carpels which in turn contain a single ovule. Seed formation ranges from 20-48 seeds per inflorescence". Redhead grass has an extensive root and rhizome system that securely anchors the plant (MDNR, 2005).
NUPHAR LUTEA It is a water plant with a big underwater rootstock. From the rootstock start the stalk of the floating leaves (about 3m long). The other leaves, instead, remain always under the water. The floating leaves have got an oval form, thy can be 30cm large and 40cm long. At the end of Spring (…) The yellow flowers are smaller (5-7 cm diameter) than the white flowers that sometimes emerge a lot from the level of water. The fruit is a big capsule and looks like a little bottle. It blooms from May to September. This plant lives in pools 3-4m depth.
LEMNA MINOR Description: floating plant not rooted. Annual plant, floating on the level of water, without stalks. Everyone is consisting of two elliptical leaves. sometimes there are two other leaves (smaller than the others). The flowers are without petals and unisexed: the male one has got two stamen, the female one ha got a carpel. The fruit is achee. Ecology: floating hydrophyte. It can form colonies (sometimes very crowd). It blooms from my and October. It lives in areas between 0 to 1600m.
LEMNA TRISULCA Description: leaves with triangular form, they don’t float but they stay on the bottom. The leaves are flat, lanceolate, they have a form of star (in a four leaves group). Every leaf, 2- mm large and 5-15 mm long, has got a stalk that link it by a right angle to the other leaves. The colour is light green or olive green and semitransparent. Every plant have got a separate root which don’t anchor to the ground. The flowers are very small e uncommon, only when the plant goes up the level of the water ( from April to June). Habitat: hot springs, pools, marshes, eutrophicated lakes. It lives in water which has neutral pH, but it can live also with 6.5 or 7.5 pH. The temperature can’t be in high temperature (not over 22°C), because it lose its colour.
ENTEROMORPHA SP. Like the other green algae, Enteromorpha has got an intense green. It has got fine blades that can be large as two inches Enteromorpha is composed of flattened green tubes. The various species of Enteromorpha differ in a varity of features such as size, branching patterns, and cell size and arrangment.
SCIRPUS LACUSTRIS It is the biggest European cane in fact it can be more than 3 meters high. It has a great rootstock (..) The stems are erected, cylindrical, dark green. The leaves are short and linear. the inflorescence is a head at the top of the steam. It is common in Italy, in lakes and pools, in marshes, rivers, channals and ditches.
MYRIOPHYLLUM SPICATUM Italian name: millefoglie d’acqua Description: underwater, deep-rooted, floating specie. Perennial plant, it is from 5 to 20 dm high. It has got blooming stem, the leaves are gathered with 5-6 whorls. The flowers are in the axils of normal leaves or smaller leaves. Ecology: it blooms from June to September. It is rare in all the Italian territory. It lives in areas between 0 to 800m.
Original description: Linnaeus 1753 dicot, perennial there are a number of water-milfoils, native and non-native, that are confusable; this water-milfoil has decidedly feathery-looking leaves plants submersed rooted, attached to the substrateplants submersed stems slender, smooth, 6 to 20 ft. long; stems reddish-brown to whitish-pink; branching several times near the water surface leaves are olive-green, less than 2 in. long, soft, deeply divided, feather-like; each leaf with a central axis (midrib) and 14 to 24 or so very slender (filiform) segments on each side of the axisleaves leaf whorls are arranged along the stems in whorls of 3 to 6 (usually 4) leaves; whorl nodes are about 3/8 in. apartwhorls of 3 to 6 (usually 4) leaves flowers on an emersed spike, held erect above the water, the spike to 8 inches long; flowers reddish; arranged in 4-flowered whorls along spike; petals 4; petals 1/8 in. long; sepals 4; stamens 8; flowering in Canada from late July to early Augustflowers4-flowered whorls along spike fruit 4-lobed; splitting into 4 nutlets roots fibrous; often developing on plant fragments
Potamogenton pectinatus Cladophora glomerata GROUP D
POTAMOGETON PECTINATUS Family: Potamogetonaceae Description :floating and rooted species. It is a perennial plant, 5-15dm high Stems terete, ca. 1 mm thick, or the main stem stouter on deep water forms sparingly branched at the base, becoming freely dichotomously branched above, 3-10 dm long. Leaves all submersed, filiform to narrowly linear, 3-12 cm long, usually 0,2-1 mm wide, 1- to 3-nerved, acute, sometimes wider with obtuse tips early in the growing season or on plants from running water; stipules adnate to the base of the leaf blade for 1-3 cm, forming a sheath about as wide as the stem, occasionally wider on the main stem, especially in deep water forms.
Spikes elongate, 1-5 cm long, with 2- 5(7) unevenly spaced floral whorls; h peduncles lax, filiform, to 15 cm long. Fruits yellowish to tawny, drying brown, obliquely obovoid, 2,7-4 mm long, rounded on the back, apiculate due to the style beak which is usually 0,3-0,5 mm long. Habitat Shallow to rather deep, fresh to subsaline water of lakes, ponds, marshes, ditches, rivers and streams; common and often abundant. Ecology: It is commune in all the Italian territory. It lives in areas between 0 to 2000m.
CLADOPHORA Cladophora glomerata (Blanket weed). The species of filamentous or string algae that causes the most concern in fresh water systems everywhere is Cladophora glomerata. This is called blanket weed (blanketweed or string algae). There are over 150 different species of cladophora so lots of different blanket weeds. Blanket weed (blanketweed) can grow at unbelievable rates when the conditions in the pond are matching the requirements of the algae such as pond water with very high light levels and with high levels of nutrients. In cases like this blanket weed can grow at more than 2 metres per day (6 feet per day!!!!)……