Giant Reed, Spanish Reed
Giant reed, also known as wild cane, is a tall,
perennial grass that can grow to over 20 feet in height. Its fleshy,
creeping rootstocks form compact masses from which tough, fibrous roots
emerge that penetrate deeply into the soil. Leaves are elongate, 1-2
inches wide and a foot long. The flowers are borne in 2-foot long, dense,
plume-like panicles during August and September.
Giant reed chokes riversides and stream channels, crowds
out native plants, interferes with flood control, increases fire
potential, and reduces habitat for wildlife, including the Least Bell's
vireo, a federally endangered bird. The long, fibrous, interconnecting
root mats of giant reed form a framework for debris dams behind bridges,
culverts, and other structures that lead to damage. It ignites easily and
can create intense fires.
Giant reed can float miles downstream where root and
stem fragments may take root and initiate new infestations. Due to its
rapid growth rate and vegetative reproduction, it is able to quickly
invade new areas and form pure stands at the expense of other species.
Once established, giant reed has the ability to out-compete and completely
suppress native vegetation.
Giant salvinia is an aquatic fern with floating
leaves. The ½ to 1 ½ inch long, oblong leaves vary in color from
green to gold to brown. The surface of the leaves has rows of
arching hairs that look like little egg-beaters. Giant salvinia
forms chains of leaves that run together to form thick mats. It can
invade most any type of aquatic system. It forms dense thick mats on
the surface of the water which restrict oxygen and light
availability, causing death of the primary produces and disrupting
the aquatic food chain. Giant salvinia is native to South America
and was first introduced into America as an ornamental aquatic
Water chestnut, scientific name (Trapa natans
L.), is an annual aquatic plant, with both surfacing and submersed
leaves. Surfacing leaves are triangular with toothed edges and an
inflated petiole, or leaf stalk, and form a rosette on the water
surface. Submersed leaves are feather-like; each leaf is divided
into segments that are whorled around the leaf stem. White flowers
form in the axils of the surfacing leaves in July. Fruit are
nut-like and "woody" with typically four sharp, barbed spines. Long
cord-like rarely branching stems can attain lengths of up to 16
feet. Water chestnut grows in freshwater lakes and ponds and slow
moving streams and rivers. It prefers calm, shallow, nutrient-rich
here for a detailed image of water chestnut.
Water hyacinth is a floating plant that occurs in lakes,
ponds, canals and other freshwater bodies. Water hyacinth forms thick mats
on the surface of the water which is detrimental to all the life forms.
Hyacinth has leathery, round leaves connected to a sponge like stalk.
Water hyacinth has stringy black roots and are also capable of rooting in
mud temporarily. The reproduction system of hyacinth is vast, however it
primarily perpetuates through seed production.
Eichhornia is native to South America (Most likely from Brazil.).
Origin in the United States may date back as far as 1884. This weed has
recently spread throughout the Southern United States.
Milfoil reproduces by a process called
“fragmentation.” Milfoil plants easily break into small pieces and
each piece can form roots. A single wisp can multiply into 250
million new plants in one year. Milfoil is readily spread between
lakes and rivers by boaters carrying plant fragments on their boats
Hydrilla (Hydrilla verticillata) is considered the most problematic
aquatic plant in the United States. This plant is native to Africa,
Australia, and parts of Asia but was introduced to Florida in 1960 via
the aquarium trade. In the 1990s hydrilla is now well-established in
the southern states where control and management costs millions of
dollars each year. On the West Coast, hydrilla has been introduced
into California and Washington. California has an eradication policy
for hydrilla infestations because hydrilla can severely impact water
delivery systems. The Washington hydrilla infestation, discovered in
1995, is the only known occurrence of hydrilla in the Pacific
Northwest and eradication efforts are ongoing.
|The white water lily is a
perennial plant that often form dense colonies. The leaves arise on
flexible stalks from large thick rhizomes. The leaves are more round
than heart-shaped, bright green, 6 to 12 inches in diameter with the
slit about 1/3 the length of the leaf. Leaves usually float on the
water's surface. Flowers arise on separate stalks, have brilliant
white petals (25 or more per flower) with yellow centers. The flowers
may float or stick above the water and each opens in the morning and
closes in the afternoon. The flowers are very fragrant. White water
lily can spread from seeds or the rhizomes.
Submerged portions of all aquatic plants provide habitats for many
micro and macro invertebrates. These invertebrates in turn are used as
food by fish and other wildlife species (e.g. amphibians, reptiles,
ducks, etc). After aquatic plants die, their decomposition by bacteria
and fungi provides food (called "detritus") for many aquatic
invertebrates. Deer, beaver, muskrat, nutria and other rodents will
consume the leaves and rhizomes of white water lily, while the seeds
are eaten by ducks.
American Elodea (waterweed)
(Elodea) is what many people commonly think of as "that aquarium
plant." It is also known by several other common names such as
Canadian waterweed, common elodea, or anacharis. The use of these
names causes it to be confused with similar-looking nonnative plants
like Brazilian elodea or hydrilla.
American waterweed is usually fairly easy to
distinguish from its more notorious relatives, like Brazilian elodea
and hydrilla. All of them have leaves in whorls around the stem.
However, American waterweed has three leaves per whorl, whereas
hydrilla and Brazilian elodea almost always have more than three
leaves per whorl. Brazilian elodea is also a much larger, bushy plant
with longer leaves.
American waterweed lives entirely underwater with
the exception of small white flowers which bloom at the surface and
are attached to the plant by delicate stalks. It produces winter buds
from the stem tips which overwinter on the lake bottom. It also often
overwinters as an evergreen plant in mild climates. In the fall leafy
stalks will detach from the parent plant, float away, root, and start
new plants. This is American waterweed's most important method of
spreading, with seed production playing a relatively minor role.
Silty sediments and water rich in nutrients favor the growth of
American waterweed and in nutrient-rich lakes, it is sometimes
perceived as a nuisance. However, it will grow in a wide range of
conditions, from very shallow to deep water, and in many sediment
types. It can even continue to grow unrooted, as floating fragments.
It is found throughout temperate North America, and is one of the most
common aquatic plants in Washington.
|Coontail, or sometimes
called hornwort, is a dark olive-green, rootless submerged
perennial plant that often forms dense colonies. Leaves are
relatively stiff, whorled with many forks and small teeth along
one edge. The tips of branches are crowded with leaves giving it a
“coontail” resemblance. Coontail reproduces by seeds and
Submerged portions of all aquatic plants provide habitats for many
micro and macro invertebrates. These invertebrates in turn are
used as food by fish and other wildlife species (e.g. amphibians,
reptiles, ducks, etc.). After aquatic plants die, their
decomposition by bacteria and fungi provides food (called
“detritus”) for many aquatic invertebrates. The fruits of coontail
are consumed by ducks and it is considered a good wildlife food.
|Tape grass is a
submersed plant that spreads by runners and sometimes forms
tall underwater meadows. Tape grass is common in still and
fast-flowing waters. Tape grass leaves arise in clusters from
their roots. They are about one inch wide and can be several
feet long. The leaves have rounded tips, and definite raised
veins. Single white female flowers grow to the water surface
on very long stalks. Tape grass fruit is a banana-like capsule
having many tiny seeds.
|The water shield is a
floating-leaved plant, but the long leaf stalks reach all the way
to the bottom where they attach to a long creeping root that is
anchored in the mud. Water shield occurs in lakes, ponds and slow
streams, and prefers water up to six feet deep.
Water shield leaves are oval and shield-shaped. Its leaf stalks
are attached at the centers of the leaf blades. Its submersed
parts and undersides of leaves are covered with a viscous
jelly-like substance. Its flowers are small, dull purple, and
emerge from the water on a stalk.
Cattails are probably the most familiar of all wetland plants.
Their swaying brown flower clusters can be seen at the edges
of ponds, rivers, lakes, or just about any place where there
is shallow, standing water for at least part of the year.
One of the more obvious things about these plants is their
size. The common cattail can grow up to nine feet in height.
One species found south of Delaware will sometimes grow to as
much as twelve feet in height! Their height, linked with their
capacity to withstand saturate soil conditions seems to have
been their real tickets to success. Throughout North America,
cattails and bulrushes are, more often than not, the
undisputed rulers of the freshwater marsh.
Probably the most distinctive thing about the cattails are
their flowers. Each cattail possesses thousands of tiny brown
flowers all tightly compressed into a compact mass on the top
of their stems. During late summer and early fall, these
structures will begin to come apart, releasing their seeds
into the wind as they do so.