European Frogbit

Frogbit

© Dave Spier

Among its many incursions into southeastern Wayne County, New York, European Frogbit (Hydrocharis morsus-ranae) can be found edging Black Creek as it leaves the Montezuma Marshes west of Savannah, just before passing under Route 31 and flowing on its way to Crusoe Creek. This Eurasian species was introduced into Ottawa, Canada in the 1930's and has since spread around the lower Great Lakes and St. Lawrence Seaway watersheds. Its spread northeastward has been limited only by water salinity. There is no limit to the south and west, so it has reached Vermont, New York and Michigan. Frogbit can form dense colonies on the surface and threatens biodiversity by crowding out native species and shading underwater plant growth needed by fish. Its rapid growth also can clog waterways and hinder recreational activities such as boating, canoeing and fishing.

 

Frogbit resembles a miniature waterlily, but its small, pistilate (female) flowers have only 3 petals around a yellow center, unlike the showy native waterlilies with their numerous petals in concentric rows. The frogbit flower resembles those of arrowhead plants, which is not too surprising because both are monocots in the Order Alismatales (although they are in different families). The plant could survive very well without flowers, because its seeds contribute very little to its spread. Instead, the plant can hitch-hike on boats, while its winter buds (called turions) sink to the bottom and lie dormant until spring, when they rise and travel with water currents. The buds grow into complete plants which then enlarge by sending out runners (called stolons) which sprout additional plants in an expanding network that can interlock with adjacent colonies.
 

Frogbit's round, floating leaves (generally two inches or less in diameter), are often notched like water-lilies and grow in rosettes (i.e., radiating from a center point). Dangling roots (to 12 inches long) seldom anchor in the bottom mud, allowing mobility on surface currents, even blowing upstream.

European Frogbit can be distinguished from its native counterpart (Limnobium spongia) by checking the leaf stems. American Frogbit has a midline groove.

Corrections, comments and questions are always welcome at northeastnaturalist@yahoo.com or connect through my Facebook page and photo page. There's also a community-type page for The Northeast Naturalist. Other nature and geology topics can be found on the parallel blogs Adirondack Naturalist and Heading Out.

Canada Thistle

Beware of tall, attractive wildflowers with prickly leaves growing in fields. Most have beautiful magenta or lavender-colored heads, but the leaves, and sometimes the stems, are edged with numerous, sharp spines to defend against herbivores looking for an easy meal. These are the thistles. They are composites, related to daisies and goldenrods in spite of the obvious differences. Most are biennials, starting as a ground-hugging rosette of prickly leaves the first year, then growing tall and flowering the second.
 

The Canada Thistle (Cirsium arvense), a misnamed alien invasive from Europe, is one of the less-obvious species here [in the northern Finger Lakes region of NY] because its light-purple heads are less than an inch high. The whole plant grows four to five-plus feet high and often forms dense colonies after spreading by underground stems. In Europe and northern Asia, it is known as Creeping Thistle. One plant's roots can spread to a three-foot diameter (or more) in one year and continue growing at this rate for many years, making it a difficult plant to eradicate. A single thistle plant can be considered biennial, but the root system is perennial and continues to put its energy into new clonal [cloned] shoots.
 

Canada Thistles form colonies from a spreading underground
 root system. Less energy goes into producing flowers.

Less energy goes into producing flowers which are usually dioecious (either male or female). Male flowers may be slightly smaller, but otherwise similar. Both are very fragrant, which is energy spent to attract pollinators and NOT humans. Female flowers produce 40 to 80 seeds per head, but the fuzzy pappus is loosely attached and often ineffective in seed dispersal.

Canada Thistle's main stems are smooth, but the deeply-lobed leaves are designed to keep you at a distance. In the spring, wear heavy gloves and protective clothing so you can return to the location and collect the young leaves, young stems and roots for food. One of the plant's nicknames is "lettuce from hell" (and it actually is related to lettuce). After removing the spines, add young leaves to salads or eat them cooked. The pithy, young stems are easier to deal with; just peel and eat raw or cooked. The roots of first year plants, before the tall stems begin, are a survival food, but they also can cause flatulence.


A crab spider is camouflaged against a Canada Thistle flower bud.

Canada Thistle is also food for wildlife, especially goldfinches and other finches that eat the seeds. Some butterfly and moth larvae eat the leaves. Look for Red Admirals, Viceroys and Painted Ladies on this thistle. The larvae of the Orellia ruficauda fruit fly parasitize the fertile seed heads, making them a somewhat-effective biological control.

In the past, a tea made from the leaves was used as a general tonic (stimulant) and diuretic to increase the loss of water from the body. Externally, it was used for skin sores and poison-ivy rash. Native Americans used a root tea as a digestive tract stimulant and dewormer. (I wonder what they used before Europeans introduced this wildflower.) At the other extreme, it was said to cause inflammation and irritation (Jacobs and Burlage). Go figure.
 

Cirsium comes from the Greek word, kirsion, from kirsos, a "swollen vein" remedied by one of the species in that genus. The species name, arvense, is Latin for "in the field." Among its other common names are "field thistle," "perennial thistle" and "cursed thistle." It was originally native to the Mediterranean and southeast Europe and likely arrived in North America during the 1600's.

Corrections, comments and questions are always welcome at northeastnaturalist@yahoo.com or connect through my Facebook page and photo page. There's also a community-type page for The Northeast Naturalist. Other nature and geology topics can be found on the parallel blogs Adirondack Naturalist and Heading Out.

Dame's Rocket

Dame’s Rocket (Hesperis matronalis) is another invasive alien, albeit an attractive one, in the mustard family. It is now widespread along roadsides, woods edges and damp thickets, but it started as a garden escape after it was introduced from Eurasia. (There's a range map on the USDA Plants Database.) Many years ago, we tried growing it on our dry hilltop, but it never took hold (probably a good thing in retro-spect), so look for it in lower areas with partial shade. It seems to prefer moist soil but avoids true wetlands.  As an example, at the Montezuma Audubon Center, it grows throughout the walnut grove and around the edges, but it’s generally absent from the open fields.

Also known as Purple Rocket, this biennial or short-lived perennial herb comes in a range of colors from pale lavender to hot pink and purple. All of the blossoms on an individual plant are usually the same color, but adjacent plants may vary widely. Light and dark colors are often mixed together in the same vicinity and sometimes you’ll find flowers with white streaks on purple petals. Rarely, several colors are mixed on the same flower. The four petals make an “X” or cross, which is characteristic of the mustards (the Brassicaceae, formerly Cruciferae). At first glance it resembles Phlox, but Phlox has five petals (the same as the number of letters in its name).

Dame's Rocket in front of Yellow Rocket (Common Winter Cress, Barbarea vulgaris)

The purple variety of Dame’s Rocket generally produces more seeds per plant and seems to be the dominant color. The stalked seed pods are thin and erect and split open when ripe. The plant usually grows several feet tall. The lance-shaped leaves are long-pointed, toothed along the margins and they alternate (i.e., are not opposite) along the hairy main stem below the flower and seed clusters.

more of the complete Dame's Rocket plant showing some of the leaves

The best time to enjoy this plant may be when it’s backlit by the afternoon sun. In the evening it gives off a lovely fragrance, probably timed to specific pollinators that rest during the day. This is reflected in another common name for the plant, the night-scented gilliflower. The scientific genus name, Hesperis, is Greek for evening.

Corrections, comments and questions are always welcome at northeastnaturalist@yahoo.com or connect through my Facebook page and photo page. There's also a community-type page for The Northeast Naturalist. Other nature and geology topics can be found on the parallel blogs Adirondack Naturalist and Heading Out.

Celandine

© Dave Spier

Celandine, Chelidonium majus, is a somewhat invasive alien with attractive yellow flowers arranged in an umbel (think inside-out umbrella), although the blossoms tend to open one at a time. Each showy flower has four petals. Black seeds growing in long capsules continue the superficial resemblance to mustards, but Celandine is actually in the Poppy family, although it's different than Celandine Poppy, a more Western native species. Celandine's somewhat grayish-green, compound leaves are irregularly lobed and scallop-edged.

This species is often called Greater Celandine to distinguish it from Lesser Celandine, Ranunculus ficaria, a quite different plant in the Buttercup family.

You can find a range map on the USDA plants database website. Celandine is widespread in the Midwest, Northeast, Eastern Canada plus outlier states like GA, NE, UT, MT, WA and adjacent BC. Clicking on some of the states will give you more refined maps down to the county level. For example, clicking NY will show Celandine's distribution across the Finger Lakes. It appears to be missing from Schuyler County, but I have photographed it in Wayne County, so that omission is an error.

When broken, Celandine's stems exude a somewhat-poisonous yellow latex that can cause dermatitis or eye irritation in sensitive individuals. A final note of warning -- Celandine is toxic due to a range of isoquinoline alkaloids so avoid ingesting the plant, and wear protection if you're pulling the plant to remove it.

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Dandelions

Can't Beat 'Em? - Eat 'Em!

© Dave Spier

What's your opinion of dandelions? Consider this: the young leaves (before the flowers appear) are edible, assuming you don't use pesticides or other chemicals on your lawn. The leaves grow in a rosette like the spokes of a wheel and average 20 per cluster. A large root system can support a double head that appears to have 40 leaves. The individual leaves are long and pointed, sometimes like an arrowhead at the tip, and coarsely toothed along both sides. The jagged teeth are often reflexed and may even point toward the center of the plant. Long ago, someone thought they resembled the teeth of a lion. In French, the name was "dent de lion" which morphed into dandelion. Other common names for this plant include blowball (a reference to the globular seed heads), lion's-tooth, wild-endive, priest's-crown and Irish-daisy.

The Common Dandelion (Taraxacum officinale) is a member of the Daisy family, also known as the Aster family and sometimes the Composite family. The complex flower head is a composite of numerous yellow rays designed to attract insects and a central disk of florets that produce the seeds. In exchange for transporting pollen, the blossom rewards insects with nectar. Bumblebees, butterflies and a host of other arthropods visit the radially symmetrical heads. What insects have you seen on dandelions?

Garden lettuce, Lactuca sativa, is a distant relative in the same family so it might be no surprise that dandelions are also food for people. Collect the young leaves and add them to a salad. They are rich in vitamins A, C and E plus iron, potassium and calcium. Slightly older leaves can be boiled to remove any developing bitterness and eaten like spinach. Young flower buds, still tucked down in the rosette of leaves, can be boiled and served with butter or they can be pickled. The buds can also be added to soups, stews and pasta dishes. The yellow flowers can be dipped in batter and fried like fritters. [A word of caution: the hollow flower stalks contain a white, milky latex that can irritate sensitive skin.] The heavy taproots can be slow-baked until brown and brittle, then ground and used like coffee in the manner of Chicory, another Composite. During the Great Depression, dandelions were an important part of the diet for many people. Likewise, in World War II, European country folk nearly eradicated this plant. Dandelions are native to Europe and were originally brought to this country for their food and medicinal value. Some homeowners would like to send these invasive aliens back.


Common Dandelion leaf and blossom

Worldwide there are about 60 species of dandelions. Many can reproduce asexually, meaning they are capable of cloning seeds without pollination. These populations are found in northern latitudes where they are presumably remnants of the Ice Age when insects may have been in short supply.

Regardless of how they are produced, the dandelion has a very effective seed dispersal system. After pollination (or cloning, as the case may be), the yellow flower head temporarily closes, then opens into an almost white ball of fluff. Each seed comes with its own parachute and the next wind will carry it on its way. A number of birds eat the seeds, and I would guess the goldfinch is among them, given the finch's fondness for thistle seed (still another member of the Composite family). Has anyone counted the number of seeds produced on one head?

Once established, the dandelion plant keeps its leaves flat to the ground, shading out anything beneath them while avoiding your mower blades above. Like any number of other plants, including certain ferns and garlic mustard, the dandelion emits chemicals that inhibit the growth of nearby vegetation, usually grass. The deep taproot resists attempts to pull the plant becasue it breaks near the surface and then grows a new rosette of leaves and new blossoms. The month of May is the peak flowering month in New York, but sporadic blossoms appear throughout the summer and late into fall, weather permitting.

If you can't admire the dandelion as a prolific survivor, then at least save your money and eat it. Given the rising cost of food, that's not a bad idea.

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Corrections, comments and questions are always welcome at northeastnaturalist@yahoo.com or connect through my Facebook page and photo page. There's also a community-type page for The Northeast Naturalist. Other nature and geology topics can be found on the parallel blogs Adirondack Naturalist and Heading Out.

Invasion

© Dave Spier

There's a wildflower that's trying to take over much of the country from Alaska to Georgia and all of the northeast to Quebec. (The USDA has a range map on their website.) It tolerates shade and crowds out native plants. Deer are repulsed by its garlic odor and flavor, making it a clever defense in hindsight. It's a prolific seed producer and if that's not enough, it releases chemicals that inhibit the growth of other nearby plants, particularly native tree seedlings. We're talking about Garlic Mustard (Alliaria petiolata, = A. officinalis and two other synonyms), a true member of the mustard family and relative of such familiars as cabbage, broccoli, cauliflower and of course, other mustards including the one used in the condiment.

Garlic mustard is a biennial. It takes two years to fully mature and go to seed. The first year, it produces only a few rounded to heart-shaped leaves as it concentrates on growing a root system. The second year, new and larger leaves (more triangular and coarsely toothed around the edges) emerge. A stem averaging one to two feet high sprouts a cluster of small, white flowers, each with four petals. These produce long, thin seed tubes that eventually dry, split and release two rows of numerous black seeds to start the process over again.

This invasive weed was brought here from Europe and Asia in the 1860's, probably to be used as a potherb. Various recipes can be found on the internet and involve using young leaves and flowerbuds and to a lesser extent flowers and seeds. This is another case of "eat it, if you can't beat it." From the looks of it, there are far more plants than we could possibly eat, so the next alternative is to pull them up by their roots, put them in a black plastic bag in the sun and eventually bury them in a long-term compost pile or otherwise dispose of the plants depending on the regulations in your neighborhood. Don't let them lay around. Even if you dry the roots and let the plant die, the seeds continue to mature. Mowing does nothing to stop the invasion because the roots quickly grow new stems and leaves and then flowers at a lower height. The seeds can lie dormant up to five years and then sprout, so the best alternative may be to trash the seed heads.

In its native Europe and eastward to India and western China, 68 insect species and seven types of fungi feed on the garlic mustard. None of these controls are present in this country. To make matters worse, deer eat our native wildflowers instead, making more room for the garlic mustard to flourish.

In Defense of Plants sent me information on a book called Garlic Mustard - from Pest to Pesto. If you have any suggestions for controlling garlic mustard, or recipes to share, please send them along with any corrections, comments and questions to northeastnaturalist@yahoo.com or connect through my Facebook page and photo page. 

Flowering Rush

At first glance, the individual flowers resemble lilies, and that wouldn't be too far off. Lilies and Flowering Rush (Butomus umbellatus) are both monocots, meaning that their seeds sprout with one initial "seed-leaf" and not two like dicots. The flower heads of Flowering Rush resemble those of chives and onions which makes perfect sense because onions are really lilies. The clusters are in arrangements called umbels (think "umbrella"); all of the flower stems radiate fom a single point at the top of the main, cylindrical stalk. Queen Anne's Lace (Wild Carrot) flowers also grow in umbels, but that plant is a dicot with deeply-dissected, feather-veined leaves.

The leaves of Flowering Rush are narrow, long-pointed and sword-like with parallel leaf veins, again similar to chives and other dicots, but it's somewhat misleading because Flowering Rush is in a plant family of its own. (In fact it's the only genus and species in that family.) It's capable of growing to a height of five feet, under the right conditions, with leaves up to 40 inches long. Most of the time it grows more in the one to four-foot height range.

Flowering Rush is an alien growing on muddy shores along the St. Lawrence Seaway and it has spread to Lake Champlain and the Great Lakes and beyond. It's a Eurasian species brought here as an ornamental in the early 1900's, and it continues to spread from Vermont to Washington and adjacent Canada.

The flowers are rather attractive with three pink and white petals alternating with three smaller pink sepals. In the center are nine pink-and-white male stamens in a radial pattern around six magenta female pistils.

Like all invasive species, it competes with desirable native wetland species, and once started, Flowering Rush is hard to irradicate because the trailing rhizomes spread under the mud and pea-sized bulbils detach, disperse in the water and quickly germinate into new plants. Varieties of this plant growing in the east also produce seeds that can spread on water currents.

There are many desirable native substitutes for Flowering Rush, including Sweet-flag, Northern Blue-flag, Pickerelweed, Giant Bur-reed, Lake Sedge, and Hardstem Bulrush. Blue-flag and Pickerelweed are attractive personal favorites.

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Picris hieracioides

This is an invasive, alien weed and I generally pull it out when I have time. It resembles a tall, multi-headed dandelion with rough-hairy, almost bristly, stems and leaves. Indeed it is a relative and like dandelions, comes from a foreign land. This one is native to the mountains in southern Spain and northern Portugal. In addition to growing in my yard, I find it proliferating along roadsides, often intermingled with its close relative, blue Chicory. The combination is colorfully attractive. All these plants are in the Aster (Daisy) family and generally considered invasive weeds.

I learned it's name as "Hawkweed Picris" from a botany professor, but the rest of the world now seems to call it "Hawkweed Oxtongue." Sorry, that just doesn't have the same ring (or is it just habit)?  The scientific name is Picris hieracioides. The genus name (Picris) comes from a Greek word for bitter, referring to the plant's roots. Members of this genus are called "oxtongues." The species name indicates its close resemblance to hawkweeds, genus Hieracium.

We've described the flowers as dandelion-like, but look closely and notice that the tip of each yellow ray has five "teeth." With age, the blossom becomes a fuzzy seed head. Without adequate sunlight, though, the plant never reaches the flowering stage and remains a basal rosette of leaves (on the ground).

The lower stem leaves are long, lance-shaped and wavy-edged, or they have short teeth separated by scalloped sinuses (see the last images before the photo notes). The upper leaves are shorter, alternate, long arrow-shaped and hug the main stem. Side branches arise from the points of attachment [axils].

Picris is a biennial, taking two years to reach maturity in sunny, open yards, fields and roadsides, and sometimes it survives another year or two as a short-lived perennial. It is related to Chicory (genus Cichorium) and both are in the Chicory subfamily (Cichorioideae).

Picris is found in isolated pockets across the Northeast into Canada, but primarily in New York and Pennsylvania. There is a disconnected invasion, again highly localized, in the Northwest from Washington to Alaska and another in Hawaii.

Photo notes: To make a leaf stand out, cast a shadow into the background. Use a tripod and a cable release [or the self-timer]. After aiming and setting the exposure [manual works best], move to throw your shadow into the background. After taking the shot, check the result and adjust as needed. I've also used notebooks and shirts to create shadows where I need them.
Lenses for this project were the 18-55mm kit lens and 100mm macro on a Canon XT.

Corrections, comments and questions are always welcome at northeastnaturalist@yahoo.com Connect with me on Facebook. In addition to my personal page (with the Gaillardia flower at the top), there is a photo/artist page, Dave Spier (photographic naturalist).

Yellow Iris

Yellow Iris at Allegany State Park in NY (Red House Lake in the background) during the Allegany Nature Pilgrimage -- © Dave Spier

Yellow Iris -- © Dave Spier

Another beautiful alien, this one escaped from water gardens...

Yellow Iris, also called "water flag," grows in the shallow edges of wetlands and ponds where the depth is generally less than 10 inches. It has spread across the United States and you can find a distribution map on the USGS website. Since I live in the Finger Lakes region of New York and travel Route 31, I mostly notice it along sections of the old Erie Canal on my way to the Montezuma Audubon Center.

The scientific name, Iris pseudacorus, comes from Iris, the Greek goddess of the rainbow (referring to the many colors in this family of plants) plus a contraction of the Greek words for "false sweetflag," referring to the similar, sword-like leaves, although sweetflag is actually an arum related to Jack-in-the-pulpit and Skunk-cabbage. Both the iris and the Sweetflag have long-pointed leaves with a prominent mid-rib.

The showy, yellow blossoms - up to four inches across - have three falling sepals surrounding three erect petals. The flowers are held above the leaves by stalks reaching a height of three to four feet. This made the species attractive to horticulturists who brought the plant to the United States in the early 1900's from its native European and North African habitats.

In suitable climates (generally the Southern Sates) it can be used to treat sewage and remove metals from wastewater. Given time this long-lived perennial can form dense, single-plant (monotypic) stands to the detriment of our native wetland plant species. It spreads by using underground rhizomes as well as seeds. Even though associated with wetlands, it can survive a drought up to three months and the seeds can survive a fast wildfire.

Be careful when handling this plant; it's poisonous and can cause skin irritation.

Yellow Iris and leaves at Allegany State Park in NY during the Allegany Nature Pilgrimage -- © Dave Spier

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northeastnaturalist@yahoo.com 

Tall Reeds (Phragmites) -- © Dave Spier

Tall (Common) Reeds, Phragmites australis, at Montezuma National Wildlife Refuge

          They're most noticeable beside the road in drainage ditches and low spots.  These tall plants with sword leaves and beige plumes extend their grasp year after year.  You may know them by several names including Common Reed, Tall Reed or Phragmites (the generic portion of Phragmites australis, the Southern Reed).  Look closely and you'll notice it's just another hollow-stem grass (though unusually large) with long leaves sheathing the stem.  The feathery plumes at the top are the flowers that turn to brown, then beige, then gray as the seeds ripen.

            During Colonial times and continuing into the 19th century, a native variety of Tall Reed grew along the coasts.  In the early 20th century, a nearly identical, but more aggressive European variety was introduced into one or more Atlantic ports.  Seeds clinging to boat hulls expanded its range along the Erie Canal.  Tall Reed has since exploded into disturbed wetlands where it spreads by seeds, dense tangles of underground rhizomes, and roots that can grow down several feet.  Colonies become dense stands that can choke waterways and crowd out any native wetland plants.  Reeds thrive in alkaline soils, so the abundant limestone and dolostone across Western and Central New York makes an ideal growing environment.  Cutting and burning are ineffective as controls.  Not surprisingly, winter salt runoff has no effect, considering reeds grow in brackish marshes along the east coast.  In fact, the salinity may suppress native freshwater vegetation, tipping the balance in favor of reeds.  This plant seems to be here to stay.

            European reeds have been used for roof thatching and cattle feed, and for making mats, pen quills and low-quality paper.  Native Americans of the Southwest fashioned arrow shafts, prayer sticks, screens and nets from the stems of reeds.  The rootstocks and seeds could be eaten as food. 

            Wildlife makes limited use of reed beds.  Red-winged Blackbirds will nest in the stands and may eat the seeds, thereby increasing dispersal of the plant.  In Europe and Asia, other species of birds are adapted specifically to life in extensive Phragmites stands.

            Comments or corrections may be sent to northeastnaturalist@yahoo.com  My other nature columns can be found at http://adirondacknaturalist.blogspot.com/ 
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PURPLE LOOSESTRIFE

Purple Loosestrife -- The Beautiful Invader
© 2008 Dave Spier
Purple Loosestrife is a tall, wetland plant sporting beautiful magenta flowers with six (sometimes four or five) petals surrounding a small yellow center. Clusters of these blossoms grow in dense whorls around a fuzzy, square stem. Pointed leaves grow in opposite pairs (sometimes whorls of three) below these flower spikes. The species is native to Europe. As early as Roman times, it was tied to the yokes of oxen in the belief that it appeased or ended strife and unruliness between the animals as they plowed. It was said to "loosen strife," hence the name loosestrife.
How could such a beautiful plant be a problem? We'll get to that in a moment.
Purple Loosestrife (Lythrum salicaria) was brought to eastern North America in the early 1800's to be used in flower gardens. If it had stayed where it was planted, we'd have little trouble. Since then it has spread westward across much of Canada and the United States. Loosestrife is a hardy perennial that takes over wetlands, crowding out the native cattails that our wildlife depends on. To give you an example, Black Terns (a declining species) depends on old, broken cattails for nesting material. The stiff, almost woody stems of loosestrife are not readily broken. Loosestrife is almost worthless from wildlife's point of view. For the most part, nothing eats it, although I once saw sparrows feeding on the seeds in late summer.
Loosestrife can also encroach on drier crop fields and pastures where it becomes a more direct economic issue. Each mature plant can produce up to 2.7 million seeds in one growing season. The rootstock also sends out 30 to 50 shoots that create a dense, monocultural web underground. This effectively chokes out "competing" vegetation.
On this side of the Atlantic, there are no natural controls for Purple Loosestrife. Our wildlife does not eat it or use it for breeding habitat. In Europe, over 100 insects feed on various parts of the plant. From these, five beetle species were selected and introduced into this country under controlled (caged) conditions. Some of the testing was done at Montezuma National Wildlife Refuge near the visitor's center east of Seneca Falls, NY. After determining that these beetles posed no threat to our desirable vegetation, they were released into the wild. Two of the insects feed on the leaves and new shoots; these are the kind released at Montezuma. A third beetle, a type of weevil, bores through the roots. The last two species eat the flowers. Some of the beetles were also released at Blue Cut Nature Center between Newark and Lyons in Wayne County, NY.
While these natural insect controls spread and multiply, a number of other steps need to be taken. So-called "sterile" varieties of garden loosestrife have been shown to cross-pollinate with wild Purple Loosestrife and produce viable seeds. Gardeners are asked to avoid planting loosestrife or any of its 26 cultivars. If it already grows in your garden, cut off the flower spikes as soon as the petals begin to drop and dispose of them in a plastic bag. Incineration is effective, but generally prohibited. If you are planting wildflowers, check the seed mix packets and make sure there is no loosestrife. Small infestations of loosestrife can be controlled by digging and hand pulling. Larger patches can be controlled by constant cutting. Chemical control usually requires a permit because of the danger to wetlands. Check with the Department of Environmental Conservation if you live in New York State or the state agency where you live.
In areas where loosestrife has already taken over a marsh, the best we can probably do for now is admire the beautiful color and wait for the beetles to arrive.
Contact Dave at northeastnaturalist@yahoo.com
(This copyrighted article and photo first appeared in The Times of Wayne County, July 28, 2008. All rights reserved.)

Invasion

This article, with slight revisions, has been reposted at http://northeastnaturalist.blogspot.com/2013/04/invasion.html

(The original copyrighted article and photo were first published in the Times of Wayne County, May 19, 2008. All rights reserved.)