The world of Aquatic Plants Will you know an aquatic invader when you see it?? SOME CHALLENGES . The Littoral Zone • all the plants: “wet green stuff” • few have conspicuous flowers • shapes and size can vary with growing conditions • they are always in wet places! Plan of Action . 1: Aquatic Plant Communities 2: Plant Structure 3: Maine’s Eleven Most Unwanted and Part 1: Aquatic their Common Native Look Alikes Plant 4: A Dry Run 5: Practice with Live Plants Communities Emergent Plant Community • shallowest zone • from moist soil to knee-deep water Life at the water’s edge can be challenging Adaptations • plants can tolerate fluctuating water levels & wave action • most have spongy, buoyant leaves and tough, interlocking roots Floating Leaved Plant Community • knee-deep to chest-deep water •submersed Life on the surface plants may reside can also be under this canopy challenging Adaptations • buoyant leaves, smooth margins, leathery texture, waxy “cuticle” • tough, elastic leaf stalks; grow rapidly to surface • some are free floating • reproduction from seeds, turions, rhizomes Submersed Plant Community • from shoreline to several meters deep • maximum depth is limited by: species specific adaptations light availability Life underwater is calmer . but still challenging! Adaptations • stems and leaves often flexible, leaves adapted to maximize surface area & gas exchange, lack cuticle • most set flowers above the surface for pollinators; heterophylly (2 leaf types) often occurs in these species • plants overwinter as rhizomes, tubers, turions (winter buds), whole plant • Reproduction primarily by clonal expansion, also root Plant Communities Overlap division, seeds Leaf Arrangement Part 2: Plant Structure Opposite Whorled Alternate Elliptical Lance shaped Leaf Types Divided Leaf Patterns ENTIRE TOOTHED or DIVIDED SERRATED Forked Branched Feather Divided Heart Shaped Triangular . and their most Part 3: common native “lOOK ALIKES” MAINE’S ELEVEN MOST UNWANTED . 3 invaders are 4 are submersed plants floating leaf plants with finely-divided leaves arranged on stems 4 are submersed plants EVERYTHING with blade or strap-shaped ELSE . leaves arranged on stems Opposite Opposite Whorled Alternate Floating Leaved Water Chestnut Plants (Trapa natans) water chestnut infestation, Mount Holyoke, MA European Frog Bit (Hydrocharis morsus- ranae) Water Chestnut Native to Europe Confirmed: CT, MA NH, NY, RI, VT, Quebec European Frog Bit European Frog Native to Europe Bit Confirmed: NY, VT Yellow Floating Heart Yellow (Nymphoides peltata) Floating Heart Native to Europe Confirmed: CT, MA, NY, RI, VT Spatterdock (Nuphar variegata) Fragrant Waterlily (Nymphaea odorata) Little Floating Heart (Nymphoides cordata) Submersed Plants with Fanwort Finely Divided Leaves (Cabomba caroliniana) Attached to Stems Eurasian water-milfoil infestation, Pleasant Hill Pond, Scarborough, ME Fanwort Native to South Fanwort America (and SE US*) Confirmed: CT, MA, NH, NY, RI, VT Variable Water-milfoil Variable Water-milfoil (Myriophyllum heterophyllum) Variable Water-milfoil Hybrid Milfoil Native to Europe & parts of US (M. heterophyllum x Confirmed: CT, ME, NH, NY, MA, RI, VT M. laxum) Eurasian Water-milfoil (Myriophyllum spicatum) Eurasian water-milfoil infestation, Kirk Lake NY Eurasian Eurasian Water-milfoil Water-milfoil Native to Europe Confirmed: CT, MA, ME, NH, NY, RI, VT Parrot Feather (Myriophyllum aquaticum) Parrot Feather Parrot Feather Native to South America Confirmed: CT, NY Maine has six lake-friendly Bladderworts native milfoils (Utricularia spp.) Large Purple • Alternate-flower • Farwell’s • Low Common • Northern • Whorled • Dwarf (leafless) Common Large Purple Hornworts (Ceratophyllum sp.) Crowfoot (Ranunculus sp.) Water Marigold Submersed Plants with (Megalodonta beckii ,Bidens beckii) Blade or Strap-shaped Leaves Attached to Stems Brazilian elodea infestation, Nepean River, New South Wales, Australia Curly-leaf Pondweed (Potamogeton crispus) curly-leaf pondweed infestation, West Pond, ME Curly-leaf Pondweed Pondweeds Curly-leaf (Potamogeton spp.) Pondweed Turions Native to Europe Confirmed: CT, MA, ME, NH, NY, RI, VT Large leaf pondweed Clasping-leaf pondweeds P. amplifolius P. perfoliatus & P. richardsonii European Naiad European Naiad (Najas minor) Native to Europe Confirmed: CT ,MA, ME, NH, NY, VT Egeria densa (South Naiads Brazilian Elodea American Waterweed, Anacharis) (Najas sp.) European Slender (N. flexilis) Brazilian Elodea Native to South America CT, NH, MA, NY, VT Brazilian elodea is a common aquarium plant Common Hydrilla Waterweed (Hydrilla verticillata) (Elodea canadensis) and Slender Waterweed (and Elodea nutallii) Form and Habit One of The World’s Most Notorious Invaders . Form Comparison Hydrilla’s Edge • Thrives in low light •Grows to depths exceeding 30 ft • Extreme rapid growth • Wide tolerance range •Propagates by clonal expansion Theirs Ours The Clinchers! Tubers and Turions are Resilient to . Tubers • Ingestion by waterfowl • Ice cover •Drying •Herbicides • Time! (Tubers remain dormant for years in Turions the sediment) Part 5 (finally!!) Common A Dry Run . Waterweed (Elodea canadensis) and Slender Waterweed (and Elodea nutallii) YOU ALL PASS! 1 You are ready to practice with real live plants! 3 1 2 4 5.