Maine Field Guide to Invasive Aquatic Plants - Brant Lake Milfoil ...

More documents

Recommendations

Info

VARIABLE WATER-MILFOIL Myriophyllum heterophyllum NOT NATIVE TO MAINE - INVASIVE I N V A S I V E P L A N T S NOTE: All leafy milfoils display a wide range of vegetative variability. Any milfoil found in Maine waters should be considered “suspicious” until a positive identification has been confirmed by someone with the appropriate expertise. Habitat: Variable water-milfoil is an extremely well adapted plant, able to thrive in a wide variety of environmental conditions. It grows well in still and flowing waters, and can survive under ice. Variable water-milfoil grows rooted in water depths from 1 to 5 meters on various substrates Terrestrial morphs including organic muck, silt, sand and gravel. Plants stranded on dewatered shorelines form erect spikes known as “terrestrial morphs.” The morphs, resembling miniature pine trees, will remain in this land-adapted form until the waters return, at which time they will “morph” back into submersed aquatic plants. Description: Variable water-milfoil is a submersed, aquatic plant with branching stems emerging from dense, spreading roots. Featherdivided leaves are arranged in densely packed whorls. (Leaves along lower portions of the stem may not be in perfect emergent flower spike water surface submersed stem Variable water-milfoil (Myriophyllum heterophyllum) whorls, i.e., some leaves may be slightly offset.) There are generally 4 to 6 leaves per whorl and Stem cross-section showing whorl of 6 leaves 5 to 14 pairs of thread-like leaflets on each leaf. The dense leaf arrangement gives this plant a bottle brush appearance. Stems may be green and slight, but most often they are thick, robust and reddish in color (even bright red). Flowers and bracts are arranged in whorls on an emergent flower spike. The tiny white flowers occur in the axils of the bracts. The bracts are bladeshaped, serrated, and more than twice the length of the flower. Winter buds (or turions) are formed in the fall at the base of the stems or on the rhizomes. 30 Maine Volunteer Lake Monitoring Program
Origin and US Range: Variable water-milfoil is native to parts of the United States, but not native to New England. Variable water-milfoil is present in Maine and all New England states except Vermont. A hybrid of this species (M. heterophyllum x M. laxum), depicted on the following page, has also been confirmed in Maine. Annual Cycle: Variable water-milfoil is an extremely hardy aquatic perennial that propagates through root division, fragmentation, turions and seeds. Flowering spikes typically emerge from the water in mid to late summer, but not all colonies produce flowers. Auto-fragmentation may occur during the growing season with stem sections developing roots even before they separate from the parent plant. Toward the end of the growing season some plants break apart and die back to their rootstalks; others overwinter intact. New growth sprouts from turions, roots, overwintering plants and plant fragments as the water begins to warm in the spring, growing rapidly toward the surface. Certain milfoils are able to hybridize with other, closely related, milfoil species. S U B M E R S E D P L A N T S W I T H F I N E LY- D I V I D E D L E AV E S Look Alikes: May be confused with bladderworts, hornworts, mermaid weeds, water crowfoots, and other leafy water-milfoils. Whorls of submersed leaves are densely arranged, giving plants a “bottle brush” appearance Flowers and bracts are arranged in whorls on the emergent flower spike; the blade-shaped serrated bracts are larger than the tiny white flowers that occur in their axils Maine Volunteer Lake Monitoring Program 31
Page 1 and 2: Maine Field Guide to Invasive Aquat
Page 3 and 4: Maine Field Guide to Invasive Aquat
Page 5 and 6: FANWORT AND INVASIVE MILFOIL LOOK A
Page 7 and 8: A m a j o r g i f t o f s u p p o r
Page 9 and 10: A C K N O W L E D G E M E N T S Mai
Page 11 and 12: With over 6000 lakes and ponds, and
Page 13 and 14: CAUTION: Even after one has ruled o
Page 15 and 16: Littoral Zone Major Plant Communiti
Page 17 and 18: plant structure In order to identif
Page 19 and 20: Stem and Leaf Structures stipule bu
Page 21 and 22: The four plants depicted below are
Page 23 and 24: 1 Floating Leaf Plants 1. Floating
Page 25 and 26: 3 S u b m e r s e d P l a n t s w i
Page 27 and 28: Invasive Plant Patrol On-Lake Train
Page 29 and 30: Variable water-milfoil I N VA S I V
Page 31 and 32: floating roots not anchored to sedi
Page 33 and 34: floating rosette of leaves submerse
Page 35 and 36: floating leaves Floating leaves oft
Page 37 and 38: Origin and US Range: Fanwort is nat
Page 39: Origin and US Range: Eurasian water
Page 43 and 44: Annual Cycle: The invasive milfoil
Page 45 and 46: Origin and US Range: Parrot feather
Page 47 and 48: Origin and US Range: Brazilian wate
Page 49 and 50: submersed stem fruits flowers leave
Page 51 and 52: Curly-leaf pondweed S U B M E R S E
Page 53 and 54: Origin and Range: European naiad is
Page 55 and 56: Origin and Range: Hydrilla is nativ
Page 57 and 58: Relative comparison of leaf-size Di
Page 59 and 60: Fragrant waterlily NATIVE LOOK ALIK
Page 61 and 62: US Range: Both of Maine’s native
Page 63 and 64: habit near base of stem flower frui
Page 65 and 66: Annual Cycle: Mare’s tail is a pe
Page 67 and 68: US Range: Both claspingleaf pondwee
Page 69 and 70: Annual cycle: Large-leaf pondweed i
Page 71 and 72: Annual Cycle: Red pondweed is an aq
Page 73 and 74: to occur in Maine. Annual Cycle: Va
Page 75 and 76: US Range: White-stem pondweed is na
Page 77 and 78: emergent flower stalk winter bud FA
Page 79 and 80: flowers Large purple bladderwort wi
Page 81 and 82: US Range: Both species are native t
Page 83 and 84: P. palustris P. pectinata Annual Cy
Page 85 and 86: Value to the Aquatic Community: The
Page 87 and 88: US Range: Both water crowfoots are
Page 89 and 90: Description: All five leafy native
Page 91 and 92:
GR0UP 1 ALTERNATE-FLOWERED WATER-MI
Page 93 and 94:
WHORLED WATER-MILFOIL COMB WATER-MI
Page 95 and 96:
LOW WATER-MILFOIL Myriophyllum humi
Page 97 and 98:
REPRODUCTIVE STRUCTURES AND OTHER D
Page 99 and 100:
Note: A subspecies, Nymphea odorata
Page 101 and 102:
Annual Cycle: Spatterdock over-wint
Page 103 and 104:
Annual Cycle: Little floating heart
Page 105 and 106:
Annual Cycle: Watershield is an aqu
Page 107 and 108:
Range: Northern snail-seed pondweed
Page 109 and 110:
Slender Pondweed Species Comparison
Page 111 and 112:
Origin and Range: Both species are
Page 113 and 114:
leaf branching habit leaf base Slen
Page 115 and 116:
oogonium calcium carbonate barbs E
Page 117 and 118:
such as the Maine DEP) assess the e
Page 119 and 120:
quick, efficient way to determine w
Page 121 and 122:
the water. Very clear lakes may sup
Page 123 and 124:
12. If you are noting dominant nati
Page 125 and 126:
OTHER INVADERS ON MAINE’S RADAR S
Page 127 and 128:
Chinese Mystery Snail (Cipangopalud
Page 129 and 130:
Unauthorized introductions of invas
Page 131 and 132:
aquatic ecosystem. This may in turn
Page 133 and 134:
ut its diminutive size and peoples'
Page 135 and 136:
plant may produce up to 2.5 million
Page 137 and 138:
Didymo is a freshwater diatom that
Page 139 and 140:
A n O u n c e o f P r e v e n t i o
Page 141 and 142:
European) Common Reed (Phragmites a
Page 143 and 144:
Page 28: Page 29: Page 30: Page 31:
Page 145 and 146:
Page 82: Page 83: Page 84: Page 85:
Page 147 and 148:
O t h e r U s e f u l R e s o u r c
Page 149 and 150:
Emergent - Plants have leaves that
Page 151 and 152:
Sub-opposite - Leaves almost opposi
Page 153 and 154:
northern bladderwort . . . . . . .
Page 155 and 156:
Najas gracillima . . . . . . . . .
show all

Maine Field Guide to Invasive Aquatic Plants - Brant Lake Milfoil ...

Create successful ePaper yourself

Delete template?

Save as template?