Plants and Algae in French Hill Pond

Introduction

French Hill Pond is well populated with water plants and algae. A plant, for the purposes of this

report, is a collection of cells that perform photosynthesis and have a support system consisting

of roots, veins and a reproduction system peculiar to that collection. Algae are colonies of cells

that perform photosynthesis but are not dependent upon a complex support system. They are

often called "non-vascular plants." Algae have no roots and veins and reproduce by direct cell

division or simple reproductive system. Algae can often form many diverse colonies of cells

from the same basic cell depending upon the conditions under which the algae colonies are

formed. French Hill Pond has a wide variety of water plants and algae mostly located on or near

the shore.

A careful examination of French Hill Pond did not identify any plants or algae that are

considered invasive, non-native species. Some of the plants and algae identified are nuisances

but native to Maine. A detailed description of each plant and algae identified is found in this

section. Vascular plants are identified by family, genus and species. The first letter of the genus

is always capitalized. The specific names of plants start with uppercase letters to distinguish the

names from general plant references.

Plants in ponds and lakes are usually divided into three categories: emergent, floating and

submersed. Emergent plants are usually on or near the shore with their roots and lower parts of

the plants in water but the upper part out of the water. If the pond or lake water level is low, the

plant may grow in mud or even relatively dry ground. Floating plants are usually rooted in the

pond or lake bottom but have parts that float on the water. Sometimes the floating part of a plant

may detach from its base and float around on the surface. Submersed plants grow entirely under

water but may be seen above the water during dry spells.

Algae colonies have well over one thousand forms that can be generated from one simple cell.

These colonies can grow rapidly and be easily seen. Algae are important to the health of a body

of water. As the simplest of the organisms in French Hill Pond, Algae will be discussed first.

Green Algae (Chlorophyta)

Stoneworts (Nitella spp.), Muskgrass (Chara spp.), and Hair or Thread Algae

The most persistent and apparent algae in French Hill Pond are colonies of Muskgrass (Chara

spp.), Stoneworts (Nitella spp.) and other Hair Algae. Muskgrass and similar algae are often

included in the category "stoneworts." These colonies consist of hair-like collections of algae

cells that are attached to rocks or the bottom of the pond. The hairs are formed when algae cells

divide and stick to one another. The conditions under which this division takes place, causes the

cells to elongate and stick together in a rod-like formation. The stoneworts develop branches

similar to leaves whorled about the main stem.

The Hair Algae are simple single hairs. Individual hairs were examined under a microscope.

About eight elongated algae cells were arranged in a single cylindrical formation but staggered to

permit cylinders to link together forming a long rod or hair. The center of the rod may have been

hollow but no veins or other means of routing nutrients were observed. The arrangement of the

cells in the cylindrical formation ensured that the cells would move to capture nutrients and be

exposed to light required for photosynthesis. The chloroplasts in each algae cell were seen

clearly. Chloroplasts are round organisms within a cell that perform the complex task of

photosynthesis for the cell. The following photograph shows a community of these hair algae

and similar plants near the shore on the east side of the pond.

Algae Community

The following photograph is a close up photograph of some individual non-vascular plants. Note

that some of these algae are branching as expected with stoneworts.

Non-vascular Plants

These hair algae increase the dissolved oxygen in the pond water. However, they fall to the

bottom and decay when they die. This decay is not good for the health of the pond because the

decaying process removes dissolved oxygen. Farmers are frequently bothered by this form of

algae and take steps to remove it from farm ponds. Some wildlife eat the algae but the growth of

the algae will often far exceed the demand that wildlife places on it. Hair algae and stonewort

communities can be destroyed by herbicides but such a control method obviates the benefits of

the algae and requires a permit in Maine, which is not likely to be granted. The best method of

control appears to be raking it out of the pond, as the algae begin to die, and composting it.

Farmers find this latter method of control desirable because it creates organic fertilizer.

However, the algae should be mixed with other composted material because some decaying

algae has a very unpleasant smell. The following photograph shows that these communities can

be very thick.

Thick Community of Hair Algae

Algae Blooms

Much of the algae in French Hill Pond exists as single cells or non-descript communities of cells

often called pond scum. These green, amorphous communities appear suddenly on the surface of

the water and often disperse quickly. The following photograph shows one of these communities

on the west side of the pond near the small brook draining the forest. The high turbidity of

French Hill Pond may indicate a significant algae presence beneath the surface.

Algae Bloom

Aquatic Mosses

Algae can also build amorphous communities in the water. These three-dimensional algae

communities can have various shapes and are often called aquatic mosses. The following

photograph shows a small example of these communities. Under some circumstances, these

algae communities can form distinct, intricate patterns. However, no intricate algae communities

were found in French Hill Pond.

Some algae communities may consist of algae that have flagella (appendages that can be waved

about) that enable them to move about. No such colonies were observed in French Hill Pond.

Amorphous Algae Community

Peat Moss (Sphagnum)

Aquatic moss is found in water. Another form of moss, peat moss, is found floating on the water

or growing in wet areas along the shore. French Hill Pond has an abundance of peat moss at the

southern end of the pond.

Like algae, peat moss is a simple organism. Technically, Sphagnum Moss is the live organism

and Sphagnum Peat Moss is the dead, decaying form of the organism. The live organism consists

of long string-like cells (called chlorophyllose cells), containing chloroplasts, separated by a

number of dead cells (called hyaline cells). The dead cells hold water and nutrients. As one layer

of the cells dies, a new layer of live and dead cells is formed on top of the dead layers.

Therefore, only the top of the organism is alive. But the dead portion is still able to absorb water

and nutrients. A dried portion of Sphagnum Peat Moss can hold as much as twenty times its

weight in water. Sections of sphagnum were examined with a microscope to positively identify

the organism.

Peat moss, the dead and dried organism, is very useful for gardening, animal bedding, filtration

of effluent from septic tanks and was even used as a dressing for wounds during war time. The

cells of peat moss contain chemicals that resist decay. Remains of mammals that died in peat

bogs are often preserved for thousands of years. The following photograph shows a community

of Sphagnum Moss on the shore of the southern part of French Hill Pond.

Sphagnum Moss

Words of caution concerning peat moss are appropriate. Sphagnum Moss will often harbor fungi

that can cause disease in humans and should be handled with care in its live or dried form. These

fungi can enter the body through wounds or cracks in the skin. Quite often a community of

Sphagnum Moss will grow on the surface of water but appear to be on solid ground. These mats

of moss are unstable and will not support the weight of a person attempting to walk on them.

Emergent Plants

Cattail Family (Typhaceae)

Cattails are emergent plants that are the most obvious water plant on or near the shore of French

Hill Pond and the island in the center of the pond. These plants will grow in virtually any wet

area and shallow water. The most common cattail in French Hill Pond appears to be the

Common Cattail (Typhaceae latifolia) but the Narrow-leaved Cattail (Typhaceae augustifolia)

was also observed.

Both species of cattails have sword-like leaves that surround the flower stem and extend above

the flowers. These plants grow from three to nine feet high. The flower stem has both male and

female flowers. The female flowers form a brown cylinder beneath a lighter-brown to yellow

spike of male flowers. The Narrow-leaved Cattail has leaves less than half an inch across, flower

heads less than ¾ inches in diameter and a gap on the stem between the male and female flowers.

The Common Cattail leaves are up to one inch across, no gap between the male and female

flowers and flower heads that are greater than ¾ inches in diameter.

Common Cattail

The rootstock of the cattail spreads out to form dense stands of plants. These plants are important

because they help to capture and filter excess nutrients and pollutants before they enter the pond.

Most of the plant is edible. The roots can be made into meal. The flower can be eaten like corn

on the cob. Young leaves can be used in salads or eaten like asparagus. Cattails were an

important source of food for indigenous Americans and early settlers.

Stands of cattails serve as shelter for shore birds and food for a number of mammals. It is

common to startle birds hiding in these stands when walking by or through cattails. Dried cattail

flower stems are often used in flower arrangements.

Bur Reed Family (Sparganiaceae)

Bur reeds are emerging plants found among the cattails in French Hill Pond and are similar to the

cattails but smaller. Two types of bur reeds were observed in the pond: Erect Bur Reed

(Sparganium americanum) and Floating Bur Weed (Sparganium fluctans). The leaves of both

species are similar to the leaves of the cattails but are typically under three feet long but from

two to over four inches wide. The under part of the leaves are keeled and arranged alternately on

the stem. Like cattails, the green, female flowers form on a stem in a ball about one inch in

diameter below green, male flowers that are in five to nine smaller heads on the same zigzag

stem. The fruit is a distinctive green, burred ball. The erect and floating species differ in that the

leaves and stems of the floating species float on the water whereas the erect species are partly in

and out of the water. The Erect Bur Reed is most common in French Hill Pond.

Erect Bur Reed

Bur reeds provide food for wildlife and, like the cattails, help filter nutrients and pollutants

before they enter the pond.

Rush Family (Juncaceae)

There is one species of rush observed in French Hill Pond, the Soft Rush (Juncus effusus). This

emergent plant consists of green spikes up to four feet high topped with clusters of brown

flowers. Leaves are lacking except for occasional basal sheaths. Wildlife may feed on the roots

and birds may find protection among the stems. The pith of this plant was used to make

inexpensive candles called "rush lights." The stems may also be used to weave mats. Like the

other emergent plants, rushes help capture excess nutrients and pollutants and stabilize the shore

of the pond.

Soft Rush

Soft Rush Flowers

Sedge Family (Cyperaceae)

One species of sedge was found in French Hill Pond, Wool Grass (Scirpus cyperinus). This

emergent plant is similar to the Soft Rush but has leaves as long as two feet on the stem and can

grow to five feet. The stem is topped with a compound umbel consisting of many spikelets with

red to brown flowers surrounded by green leaf-like bracts. Like the other emergent plants, sedges

provide food for wildlife, help filter excess nutrients and pollutants and stabilize the shoreline.

Wool Grass

Floating Plants

Water Lilly Family (Nymphaeaceae)

Yellow Pond Lilly (Nuphar variegata)

The Yellow Pond Lily (Nuphar variegata) is the most obvious floating plant in French Hill Pond.

It is also called Spatterdock, Cow Lily or Bullhead Lily. The leaves of the spatterdock found in

Maine are heart-shaped, from about three to ten inches long and float on the water. The leaf

stems are thick and have a cross-section that resembles a smile. A more southern species called

the Common Spatterdock (Nuphar advena) is similar but the leaves stick up out of the water.

The flower of the spatterdock is a distinctive yellow ball up to about three inches wide with

about a half dozen yellow petals. When the petals open they form a vase-like structure

surrounding a yellowish-green, disk-like pistil with numerous stigmatic surfaces.

Spatterdock Leaves and Flower Ball

These plants die each season and contribute significantly to the decaying matter in the pond. The

leaves are eaten by wildlife and provide shade for fish and other aquatic life.

Fragrant Water Lily (Nymphaea adorata)

The Fragrant Water Lily (Nymphaea adorata) or White Water Lily is common in Maine lakes

and ponds but was not observed in French Hill Pond. It is similar to the Spatterdock but the

leaves are more rounded and the flowers are white or pink. It could become established in French

Hill Pond.

Menyanthaceae Family (Menyanthaceae)

Little Floating Hearts (Nymphoides cordata)

Little Floating Hearts (Nymphoides cordata) were observed in French Hill Pond. They resemble

Spatterdocks but have smaller leaves, only about 2 inches wide. The indentations at the base of

the leaves are also wider than the indentations of the spatterdock. The margins of the Little

Floating Hearts leaves are often slightly scalloped. The leaves are mottled with purple on top.

The flowers are small and white. Tuberous roots dangle under the leaves from the stem. Each

leaf has its own stem descending to the bottom of the pond.

Little Floating Hearts

Bur Reed Family (Sparganiaceae)

Floating Bur Reed (Sparganium fluctans)

As indicated in the section on emergent plants, French Hill Pond also has communities of

Floating Bur Reed (Sparganium fluctans). These plants are normally found in cold ponds.

Floating Weeds in the South End of the Pond

The photograph above shows weeds in the south end of the pond. The longer, linear, leaves are

Floating Bur Reeds. See the description of Bur Reeds under emergent plants for more detailed

information.

Cabombaceae Family (Cabombaceae)

Watershield (Brasenia schreberi)

Watershield (Brasenia schreberi), also called Water Target, is a native Maine plant not observed

in French Hill Pond. However, it may appear in the future. It has floating, oval to football-shaped

leaves with stems that connect to the leaves on the center of the undersides. The flowers are

purple and are produced on separate stalks. It prefers pond bottoms that are rich in organic

matter. The bottom of French Hill Pond is rocky.

Submersed Plants

French Hill Pond has a number of submersed plants. These plants may have leaves that float on

the water or stick above the water but most of the plant is submerged and has distinctive leaves

that are always submerged.

Submersed plants oxygenate the water while they are viable. However, their decay will remove

oxygen from the water. Their consumption by animals can help limit the effects of decay.

Pondweeds Family (Potamogetonaceae)

Pondweeds of the family Potamogetonacee have both submerged and floating leaves that help

oxygenate the pond and provide food for wildlife. The leaves tend to be relatively large, broad

and substantial as compared to other submersed plants.

Large-leaf Pondweed (Potamogeton amplifolius)

Large-leaf Pondweed

The Large-leaf Pondweed (Potamogeton amplifolius) shown above is common in French Hill

Pond. The floating leaves are oval and each is at the end of its own stem. The submerged leaves

are larger and more elongated than the floating leaves. Some of these submerged leaves can be

seen in the photograph. The submerged leaves tend to be wavy and fold inward toward the mid

vein. The stems of the upper submerged leaves and the floating leaves are attached to the main

stem at a single point. The flower is an emergent spike growing from this point on the main stem.

Variable Pondweed (Potamogeton gramineus)

Variable Pondweed (Potamogeton gramineus) is another common plant in French Hill Pond. The

floating leaves of this plant are similar to the large-leaf pondweed but smaller. They are about an

inch wide and up to two inches long. Their petioles (stems that attached the leaves to the main

stem) are longer than the leaves' lengths. The submerged leaves are distinctly linear, alternately

arranged, attached directly to the main stem (they lack petioles), are less than one inch wide and

are from an inch to three inches long. The floating leaves of this plant will be on the same stem

as submersed leaves but many submersed leaves are not associated with floating leaves.

Variable Pondweed submerged leaves

The flower is a cylindrical spike about an inch long. The fruits are egg-shaped with a ridge along

one side and have a point called a beak.

Submerged Variable Pondweed

As the name indicates, this plant has a number of varieties. The leaves can be small or large. The

plants can be bushy or sparse depending upon the environmental conditions. In French Hill Pond,

they tend to be bushy with relatively large leaves.

Variable Pondweed Community

Floating-leaved Pondweed (Potamogeton natans)

The Floating-leaved Pondweed (Potamogeton natans) was found in the communities of other

pondweeds. The floating leaves are much like the floating leaves of the Variable Pondweed but

the submersed leaves are very narrow and long

.

Floating-leaved Pondweed

Small Pondweed (Potamogeton pusillus)

Small Pondweeds (Potamogeton pusillus) were also found among the other pondweeds. These

plants have only submerged, linear leaves up to three inches long that have no petioles (stems

that attach the leaves to the main stem). The flowers and fruits form as spikes at the extremity of

the plant.

Fern Pondweed (Potamogeton robbinsii)

A few Fern Pondweeds (Potamogeton robbinsii) were spotted. The leaves of this plant are linear

and arranged in two ranks that form a fern-like arrangement. The flowers and fruits form as

spikes at the tip of the plant. Fern Pondweeds are seen in the middle and to the left side of the

photograph below.

Fern Pondweeds

Ribbon Pondweed (Potamogeton epihydrous)

The Ribbon Pondweed (Potamogeton epihydrous) was found in French Hill Pond. These plants

have floating leaves that are similar to the other pondweeds but there are numerous floating

leaves on a main stem that are arranged alternately. The submerged leaves are long and narrow

and striped.

A mixed pondweed community

Other Pondweeds

Other pondweeds that are common in Maine lakes that appeared to be present in French Hill

Pond are the Clasping-leaf Pondweed (Potamogeton perfoliatus), Flat-stem Pondweed

(Potamogeton zosteriformis) and the Spiral Fruited Pondweed (Potamogeton spirillus). Only the

Flat-stem Pondweed was definitively identified.

Tape-grass Family (Hydrocharitaceae)

The Tape-grasses (Hydrocharitaceae) is a family of aquatic plants that include both freshwater

and saltwater species. The Elodea genus in this family are often called waterweeds. Three of

these species were identified in French Hill Pond but not in great numbers. Non-native, invasive

species of this family were not found in French Hill Pond.

Common Waterweed (Elodea canadensis)

The Common Waterweed (Elodea canadensis) is entirely submerged except for small white or

purple flowers that stick above the surface. The leaves are linear and grow in whorls of three

about the stem. Other names for this plant are American Waterweed and Canadian Waterweed.

This plant can become a nuisance by rapidly multiplying and monopolizing shallow areas of the

pond. Elodea canadensis prefers mud and bright lighting. Given the rocky bottom and turbidity

of French Hill Pond, it is not likely to become a problem.

Slender Waterweed (Elodea nuttallii)

The Slender Waterweed (Elodea nuttallii) is another freshwater plant that is entirely submerged.

It is similar to the Common Waterweed except that the leaves come to a sharp point. Another

name for this plant is Western Waterweed.

Wild Celery (Vallisneria americana)

Wild Celery

Wild Celery (Vallisneria americana) is an entirely submersed plant that has no resemblance to

the celery most people know. The leaves grow from the roots of the plant up to two feet long and

are less than an inch wide. The tips of the leaves are somewhat blunt. The flowers form on a

stem growing from the root system independent of the leaves. The flowers will break off from

the stem and float on the water. The fruit is formed underwater when the flowers are pollinated

by contact with another flower. As shown in the photograph above, Wild Celery was found in

French Hill Pond.

Water Milfoil Family (Myriophyllum)

Water Milfoils (Myriophyllum) is a family of over 40 freshwater plants. The translation of the

Latin family name is "too many to count leaves." The leaves of these plants are finely, pinnately

divided like very fine needles on an evergreen tree. The non-native, invasive species of this plant

family are listed as serious threats to Maine waters. Fortunately, no Water Milfoils were

identified in French Hill Pond although their presence cannot be ruled out.

Bladderwort Family (Lentribulariaceae)

Bladderworts are common in Maine lakes and ponds. They are carnivorous plants that feed on

microscopic organisms and even insects. Tiny bladders located on the stems open as an organism

brushes against trigger hairs. The bladder opens sucking the organism into the bladder where it is

digested. Their leaves are finely-branched. The flowers are similar to snapdragons.

Possible Bladderwort Remnants

The great amount of hair algae and similar plants in French Hill Pond made the search for plants

like bladderworts difficult. The photograph above seems to show bladders on the remnant of a

bladderwort plant. Separation of the masses of hair-like plants in French Hill Pond, as was done

for the photograph, usually destroyed the distinctive features of some plants. One would expect

to find the Common Bladderwort (Utricularia macrorhiza or Utricularia vulgaris) in French Hill

Pond. This bladderwort would be highly desirable because it eats mosquito larvae. The possible

bladderwort shown above would be a smaller species consuming microscopic creatures.

Expected but Unobserved Submerged Plants

There are several plants that one would expect to see in Maine ponds and lakes but were either

not observed at all or not positively identified in French Hill Pond. However, the following such

plants could become established in French Hill Pond.

Coontail (Ceratophyllum demersum) is a plant with whorls of nine to ten, thin leaves around the

stem but was not positively identified. Quillworts (Isoetes spp.) look somewhat like Wild Celery

but their leaf tips are pointed instead of blunt. No quillworts were positively identified in French

Hill Pond.

Water lobelia (Lobelia dortmanna) are often found in Maine ponds and lakes particularly if the

water is acidic. It has oblong leaves arranged in a basal rosette underwater. The white, pink or

blue flowers are on an erect stem that extends above the water. No Water Lobelia were positively

identified in French Hill Pond but some underwater leaf arrangements were similar to the

expected configuration of this plant.

Naiads (Najas spp.) are plants similar to stoneworts, are common in Maine freshwater but were

not observed in French Hill Pond. Water Marigolds (Bidens beckii) and Water Crowfoots or

Water Buttercups (Rannunculus aquatillis) are also common in Maine freshwaters but were not

seen in French Hill Pond. These plants have whorls of leaves around the stem underwater. The

water Marigolds have emergent leaves and yellow flowers above water that resemble marigold

plants. The Water Crowfoots have white or yellow flowers that resemble buttercup flowers on

the tips of leafless stems above the water.

Propagation, Eradication and Introduction of New Species

Water plants have evolved strategies for propagation that ensures the survival of the species

under extreme environmental conditions. Virtually all water plants reproduce by producing fruits

and seeds that can establish a new plant elsewhere. Many water plants have rhizomes that are

creeping, underground stems from which new plant sprouts can grow. Tubers or bulbs may

develop on the rhizome that can produce a new plant even if the rhizome is cut off from the

parent plant. Many water plants also produce turions that are buds formed on the stem. Turions

can drop off the plant in the fall, overwinter and produce a new plant in the spring. Turions are

sometimes called "winter buds."

These four means of reproduction make the eradication of water plants very difficult. If a water

plant is to be eradicated, all four means of reproduction must be thwarted. Water plants targeted

for eradication should never be simply pulled up. The rhizomes and tubers must be completely

removed. The eradication process must begin before the plant goes to seed or produces turions.

New plants should not be introduced into the pond. Watercraft that was used on another body of

water should be inspected for plants and cleaned before using them in French Hill Pond.

Aquarium plants should never be introduced into bodies of water. Many common aquarium

plants are not native to Maine and become very evasive when introduced into Maine waters.

Summary

No non-native, invasive plants were found in French Hill Pond. However, French Hill Pond has

an abundance of plants. This pond can be categorized as "productive." There are large emergent

plant communities that should be encouraged because they filter water and remove nutrients

before the water enters the pond. The floating and submerged plants oxygenate the water but

their decay can have undesirable results. These plants are eaten by wildlife, which should be

encouraged. However, some of the algae is very invasive and raking it out of the pond at the end

of the growing season may be desirable.

Water plants are difficult to eradicate once they are established. New plants should not be

introduced and if established plants must be eradicated, the process must be thorough.