QUICK REFERENCE How to choose a weed control product Classify The Weed: Emersed, Submersed, Floating, or Algae Determine Specific Weeds with Weed Chart Select A Product: What Controls What Determine Quantity To Order based on product coverage

 

WEED CHART

Algae Cellular, lower weed form. No distinguishable stem or leaf. Scum and Chara are common.

 

CHARA (Chara vulgaris): Leaf-like structures whorled around hollow stem. Dense growth attached, but not rooted to bottom. May carpet large areas of a lake or pond bottom. Strong musky odor when crushed. May have a gritty texture due to mineral deposits on the surface. Do not confuse with higher weeds.
FILAMENTOUS ALGAE: Individual filaments. A series of cells joined end to end that give a thread-like appearance. Often referred to as pond scum. Forms surface mats. Growth begins at the bottom and rises to the surface as a bubble-filled mass. May also form fur-like growths on logs and rocks at the bottom.
PLANKTONIC ALGAE: Microscopic growth often visible as a greenish tinge suspended in the upper few feet of water. Severe blooms may resemble pea soup and actually thicken the water.

 

Emersed Growing in shallow water with leaves or stems above the water.

 

AMERICAN LOTUS (Nelumbo lutea): Floating leaves are circular with stems attached to the center of the leaves underside. Emersed leaves are also circular and depressed to the center of the upper surface. Flowers are solitary pale yellow and composed of numerous petals. The seed pod is in the flowers center with seeds embedded in its surface.
BULRUSH (Scirpus spp.): Leaves may or may not be present. If present, they appear as a continuation of the stem. Stems are tall and smooth and either round or triangular in shape. A loose cluster of brownish flowers and seeds is located near the tip of the stem.
CATTAIL (Typha latifolia): Leaves are tall and flat. Stems are tall, round and unbranched. Flower is the distinctive cigar-shaped cattail which is green in early summer and turns brown and fuzzy in fall. This weed has an extensive root system. Difficult to control when well established
GRASS FAMILY (Gramineae): Many kinds of grasses grow in damp places and at times are found in water. Leaves are long and slender, usually ten times as long as wide. Veins within the leaves run parallel to each other. Leaves are arranged alternately on the stem. Most grasses are emersed including but not limited to Giant Cutgrass, Giant Foxtail, Maidencane, Paragrass, and Sawgrass. Other grasses may be submersed including Wild Rice and Manna Grass.
PICKERELWEED (Pontederia cordata): Leaves are heart shaped at the base. Veins are very fine and numerous. Flowers are blue-purple and crowded on elongated terminal spikes. Each flower has six petal like parts united below into a tube.
PURPLE LOOSESTRIFE (Lythrum salicaria): Leaves slightly heart-shaped at base coming to a point at leaf tip. Leaves small and more numerous near tip. Stems rigid, four-sided and have fine hairs on them. Leaves oppositely arranged on stem usually in pairs. Flowers bright purplish on a spike closely attached to stem.
REED GRASS (Phragmites maximus): Leaves are long and flat with parallel veins. Stems are tall and round with alternately arranged leaves. Flower of weed is made up of spikelets with long silky hairs such that this portion of the weed may appear as a silky mass. Stout rootstocks make this weed difficult to pull out.
SMARTWEED (Polygonum hydropiperoides): Leaves are oblong and smooth on the edges. Stems are distinctly jointed with leaves alternately arranged. The lower portion of the stem is rooted at the joints. Flowers are small and tightly clustered and are white or pink in color. Weed may be emersed in shallow water or completely submersed with only flowers visible above surface in deep water.
SPATTERDOCK (Nupharadvena): Leaves heart shaped at base, shiny and smooth. Some leaves float but most stand above water. Flowers are solitary on a long stalk slightly above the water surface, yellow with green outer petals. Roots become very thick once the weed is well established.
WATER CHESTNUT (Trapa natans): Submersed leaves threadlike far apart on the stem. Floating leaves are nearly triangular or diamond shaped toothed in the upper half on inflated stems. Flowers have four white petals.
WATER PENNYWORT (Hydrocotyle): Leaves round with low rounded lobes. Attached at center to a stem. A leaf is about the size of a half dollar. Stems extend from a horizontal root in shallow water. Flowers arise in groups from smooth stems. Each individual flower has five small white petals. Often rooted in mud forming dense mats.
WATER PRIMROSE (Jussiaea repens): Leaves are lance shaped with smooth edges. Veins in leaves are evident. Stems and leaves are hairy. Leaves are numerous and alternately attached. Flowers are bright yellow and develop at the top of the weed.
WATER WILLOW (Dianthera americana): Leaves long, narrow and tapered at each end. Branched veins evident. Edges are smooth. Stems are usually unbranched with leaves oppositely attached. Flowers born on spikes, purplish in color.

Floating Growing unattached or rooted with floating leaves. .

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DUCKWEED (Lemna minor): Leaves the size of a pencil eraser. May be observed individually or in clusters upon close observation. Small root hairs may be seen hanging down from the underside of the leaf. No stem is distinguishable. Heavy growth will blanket the surface with many inches of growth. Duckweed is not interconnected as is Filamentous Algae. Do not confuse with Algae.
FALSE LOOSESTRIFE (Ludwigia palustris): Leaves both floating and submersed. Oblong and narrow near the stem. Leaves oppositely attached to stem, most often in pairs. Stems rooted at the joints. Forms tangled mat on the surface.
WATER SHIELD (Brasenia schreberi): Leaves are oval in shape with smooth edges. Stem is attached to the middle of the leaf. A clear jelly-like coating covers the underside of the leaves and stems on mature weeds. A dull purple flower develops in early summer. Treat before jelly-like coating develops.
WHITE WATER LILY (Nymphaea odorata): Leaves large, round and slit to the center. Underside of leaf is often purplish. Stem is below the surface. Roots are thick and fleshy, most often buried in mud. Flowers are white with multiple rows of petals born on a single stalk at or above the surface. May be confused with Spatterdock.

 

Submersed Growing in deeper water entirely below the surface.

 

BLADDERWORT (Utricularia): Finely divided leaves scattered along the stem with numerous bladder like structures on leaves. Stems have many branches and are densely leafy at the tips. Flowers are yellow and rise above surface.
BUSHY PONDWEED (Najas gracillima): Leaves are narrow with tiny spines along the edges. Slightly enlarged at the base. Stems slender with frequent branching. Leaves oppositely attached, or in groups of two or more at a node. Leaves are densely concentrated at the tips. May be confused with Chara. Chara has a strong odor when crushed, Bushy Pondweed does not.
CLASPING-LEAF PONDWEED (Potamogeton richardsonii): Leaves wide and wavy with smooth edges. Broad base clasps the stem. Upper stem commonly branched and leafy. Leaves are alternately arranged on stem. Solid tightly packed spike of nutlets at tip of weed rises above water surface.
COONTAIL (Ceratophyllum demersum): Leaves whorled around the stem and have a serrated appearance (see leaf detail). Spacing between leaf whorls is variable. Consequently, weeds may be long and sparse or bushy. Near the end of the stem leaves and whorls are crowded. Branches are forked repeatedly. Do not confuse with Chara.
CURLY-LEAF PONDWEED (Potamogeton crispus): Leaves thin with wavy and finely serrated edges. Stems branched. Upper leaves are often crispy and appear waxy. Leaves alternately on stem. Flowers born on spikes rise above the water surface.
ELODEA (Elodea canadensis): Broad oval leaves, usually four in number, arranged in whorles around the stem. Whorles are compact near the growth tip with spacing between the whorles Between gradually increasing further down the stem.
FLOATING-LEAF PONDWEED (Potamogeton natans): Leaves both floating and submersed. Submersed leaves are long and narrow. Floating leaves are oblong and slightly heart-shaped at base. Parallel leaf veins are evident. Stems occasionally branched. Leaves are alternately arranged on stem. Solid tightly packed spike of nutlets at tip of weed rises above water surface.
HORNED PONDWEED (Zannichellia palustris): Leaves are long and threadlike. Oppositely arranged on the stem unlike other pondweeds. Seeds found at the leaf base, flattish in shape, and serrated on one side.
HYDRILLA (Hydrilla verticillata): Stem is long and branched with oppositley arranged leaves at the bottom and whorles of 3 leaves on the upper portion of the plant. Leaf is oval-shaped with margins toothed. There are pointed spines on the mid-rib of the underside of the leaf.
LARGE-LEAF PONDWEED (Potamogeton amplifolius): Leaves both floating and submersed. Submersed leaves are large, oblong, wavy, and taper to the stem. Floating leaves are oval-shaped. Parallel leaf veins are evident. Stems are seldom branched. Leaves alternately arranged on stem. Solid, tightly packed spike of nutlets at tip of weed rises above water surface.
LEAFY PONDWEED (Potamogeton foliosus): Short glasslike leaves which measure one to three inches long and branch freely on a slender stem. Leaves arranged on the stem. alternately attached. Clumps of four to eight fruiting bodies attached to a center stem by a short reed stalk that rises above the water surface.
MILFOIL (Myriophyllum): Leaves whorled in groups of four. Each leaf is divided into many thread-like leaflets extending from a central rib (see leaf detail). Forms tangled mats at the surface. Seed heads develop in mid to late season and may extend above the water surface. Treat when weeds are actively growing before flowering occurs
PARROT FEATHER (Myriophyllum Brasiliense): Also a type of Milfoil. Leaves whorled in groups of four to six. Each leaf is divided into eighteen pairs of thread-like segments resembling a feather (see leaf detail). This species differs from other Milfoils by having its foliage partially out of the water. Emersed foliage is bright green.
SAGO PONDWEED (Potamogeton pectinatus): Leaves are stiff, narrow and thread-like. Stems branched with leaves alternately attached. Spreading leaves resemble a fan with an overall bushy appearance. Nutlets appear like beads on a string. Tiny green flower appears on a spike along with nutlets above the water surface.

 

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