Every year on the 30th of March, National Take a Walk in a Park Day is celebrated to acknowledge the importance of taking a walk through a park, understanding the health benefits of doing so, and appreciating a reconnection with others as well as nature.
Taking a walk at a local park is an excellent way to clear one’s mind from the stresses of the day, re-energize, socialize with people, and, at the same time, improve your health. Walking has amazing health benefits, from increasing heart activity (which, in turn, helps to lower blood pressure and decrease the chances of cardiac arrest), to lowering the risk of type 2 diabetes, obesity, and even certain types of cancer. Read more about the benefits of “green exercise” in my prior post, International Day of Forests.
Today is a great opportunity to discover a new park near you and explore it.
If the Bauer Environmental Park in the Town of Colonie is new to you, I encourage you to make time to visit it today or this weekend.
From either parking lot, a short path leads to the loop, which is a flat, ADA-accessible trail of about one mile (~90% boardwalk) that takes you on a circle through the woods. A few bridges cross the stream that meanders through the park.
The trails are family-friendly and ideal for walking, hiking, nature enjoyment, and cross-country skiing. Interested in birdwatching? View the list of birds observed at this park. Want to view wildflowers here later this year? View my wildflower field guide for this park.
A definition: a plant that is not desired where it is growing.
A perspective: “A plant whose virtues have never been discovered.” – Ralph Waldo Emerson
For a little insight on the secret origin of weeds, view this.
Read this helpful article that provides some clarifying distinctions between “weed,” “native,” “wildflower,” and “invasive.”
As to ‘appreciation,’ I am referring to the “a full understanding of a situation” definition of that word.
To that end, each of the following plants has ‘weed’ in its common name. As we reflect upon such plants on this day, read some curious factoids about these particular “weeds.”
Edible and Medicinal Use: Leaves as a potherb. The whole plant is astringent, carminative (agent that prevents or relieves flatulence in the gastrointestinal tract and, in infants, may help in the treatment of colic), demulcent (relieves irritation of the mucous membranes in the mouth), diuretic (induces urination), expectorant (helps clear mucus from airway), laxative (loosens stool and increases bowel movements), refrigerant (gives sensation of coolness or relieves feverishness), and vulnerary (wound healing). Chickweed has a very long history of herbal use, being particularly beneficial in the external treatment of any kind of itching skin condition. A decoction is used externally to treat rheumatic pains, wounds, and ulcers. Read about how to prepare a skin salve from Common Chickweed and English Plantain (Plantago lanceolata).
Where Found: Clearings in forests, open banks of streams, successional fields (where the soils are exposed or thin), cultivated ground, roadsides, disturbed areas, and waste areas.
Folklore: The essential oil of the plant is said to be a useful insect repellant and fungicide.
Edible and Medicinal Use: Young leaves are edible; best dried and stored for later use to help flavor meals (flavor is similar to tarragon). For medicinal uses, it can be harvested at any time that it is in flower and is best used when fresh. Valued most for its astringency, it is used in the treatment of gastro-intestinal problems such as diarrhoea and dysentery. It is said to be a very effective treatment for bleeding haemorrhoids. The whole plant is antirheumatic (reduces or prevents joint damage associated with inflammatory disorders of the joints), astringent, balsamic (soothing, restorative), diuretic (induces urination), emmenagogue (stimulates or increases menstrual flow), styptic (stops bleeding from shallow surface injury), tonic (invigorates), and vermifuge (expels parasitic worms).
Wildlife Value: Bee visitors (such as Halictid bees) suck nectar or collect pollen, fly visitors (such as flesh flies (Sarcophaga spp.), Muscid flies, Syrphid flies, and Tachinid flies) suck nectar or feed on pollen, while other floral visitors (such as Perilampid wasps, Sphecid wasps, and Vespid wasps) feed on nectar. These flowers also provide an important nectar source during fall migration of the Monarch Butterfly (Danaus plexippes). Animals usually avoid browsing the foliage because it is resinous and bitter.
Where Found: Roadsides, pastures, lawns, successional fields, and disturbed areas
Folklore: In Celtic mythology, this plant was believed to have magical powers and was used in spells and charms to bring good luck and ward off evil spirits.
Edible and Medicinal Use: No known edible uses. Its leaves and flowers have been used to make tea, which is said to have anti-inflammatory, antioxidant, and diuretic (induces urination) properties.
Where Found: Marshes, wet fields, ditches, seepage areas, and swamps
Folklore: Joe Pye has been associated with an American Indian healer, possibly named Jopi, who used the plant to cure typhoid fever; he is also credited with having halted a typhus epidemic in Colonial Massachusetts. A peer-reviewed study suggests that Joe Pye was indeed a Mohegan sachem (a chief) named Schauquethqueat who lived in the mission town of Stockbridge, Massachusetts from 1740 to 1785 and who took as his Christian name, Joseph Pye. Read more about the history of this man and how his name became associated with this plant.
Edible and Medicinal Use: No known edible uses. A tea made from the whole herb is diuretic (induces urination). It is used in the treatment of kidney complaints, painful urination, rheumatism, etc. The leaves and stems are harvested in the summer before the flower buds open, and are dried for later use. Externally, a decoction of the roots is used as a wash on rheumatic joints. The roots are harvested in the autumn and dried for later use.
Wildlife Value: The nectar of the flowers attracts honey bees, bumblebees, long-horned bees (Melissodes spp.), leaf-cutting bees (Megachile spp.), bee flies, butterflies, skippers, and moths. Some bees may also collect pollen. It is a larval host to the Clymene Moth (Haploa clymene), the Common Eupithecia (Eupithecia miserulata), the Ruby Tiger Moth (Phragmatobia fuliginosa), and the Three-Lined Flower Moth (Schinia trifascia). The seeds of Joe-Pye Weed species are a minor source of food to the Swamp Sparrow (Melospiza georgiana).
This week, I’m featuring Speckled Alder (Alnus incana ssp. rugosa) as one of our local wildflowers that begins to bloom at this time.
PLEASE NOTE:Culturally Significant Plant = Ethnobotanic Uses: Speckled Alder was used by American Indians in a wide variety of medicinal uses in the treatment of numerous ailments. Read more.
Description:
Speckled Alder is a common, fast-growing, large, multi-stemmed wetland shrub, often forming dense thickets from root suckering as well as a process called “layering”, where low branches take root then detach from the mother plant and grow independently. Stems are usually numerous from the base, but individual trunks can grow up to 6 inches in diameter, occasionally taking the form of a small tree.
Twigs are brown to reddish brown to grayish, with scattered white lenticels (pores); new growth is hairy, but becomes hairless and smooth the second year. Older bark is grayish to reddish brown with pale horizontal lenticels (pores).
Leaves are alternate and simple, egg-shaped to elliptic and pointed or blunt at the tip, 1½ to 4½ inches long and 1 to 3 inches wide on a hairy stalk up to ¾ inch long. Some leaves may have shallow lobes. Leaf margins are coarsely double-toothed. The upper surface is a dull dark green, hairless to sparsely hairy, and the lower surface is paler and hairy, especially along the veins.
Alders are among the first plants to flower in spring. Male and female flowers are borne separately on the same plant (monoecious), in clusters called catkins, blooming in very early spring before leaves emerge. Two to 6 male catkins form drooping clusters at the tip of 1-year old twigs, 1¾ to 3½ inches long. Female catkins are red, oval to short-cylindric, about ½ inch, in one or more separate clusters near the male catkins on the same branch, with 1 to 4 catkins in a cluster.
Fertilized female catkins become stout, oval to egg-shaped, cone-like clusters up to about 2/3 inch long. These green fruits mature to reddish-brown in fall, resembling small pine cones with 5-lobed scales. They release their seed in the summer, but the cone structure generally remains intact through winter. Each cone contains two small rounded brown nutlets 1/8 inch long that may have two small leathery wings.
No known edible uses due to its strongly astringent and emetic (induces vomiting) qualities.
Speckled Alder was widely used medicinally by American Indians who used it to treat a variety of ailments, such as anemia, internal bleeding, urinary problems, sprains, bruises or backaches, itches, and piles. A tea was made to cure diarrhea and to treat upset stomachs or rheumatism. A mixture of root bark and molasses was used in the treatment of toothaches, and either its inner bark or a decoction made from it were applied as a compress on rashes, sore eyes, and swellings. The Chippewa mixed alder root scrapings with powdered bumblebees and fed the mixture to women whom were having difficulty during childbirth.
While Speckled Alder has been little used in modern herbalism, its bark is alterative, astringent, emetic, laxative, ophthalmic, stomachic and tonic.
Wildlife Value:
Speckled Alder is a host plant to the caterpillars of a significant number of moths and butterflies:
Speckled Alder seeds, buds and catkins provide food for small animals and birds, such as American Goldfinch (Spinus tristis), American Woodcock (Scolopax minor), Black-capped Chickadee (Poecile atricapillus), Common Redpoll (Acanthis flammea), Pine Siskin (Spinus pinus) and Ruffed Grouse (Bonasa umbellus). However, research suggests that Ruffed Grouse will typically reserve these as a midwinter survival food, consuming them only when other food sources become scarce.
More importantly, Speckled Alder thickets provide safe nesting habitat for Alder Flycatcher (Empidonax alnorum), American Goldfinch, Common Yellowthroat (Geothlypis trichas), American Woodcock (when located in upland sites), Red-winged Blackbird (Agelaius phoeniceus), Swamp Sparrow (Melospiza georgiana), White-throated Sparrow (Zonotrichia albicollis), Wilson’s Warbler (Cardellina pusilla), Yellow-bellied Flycatcher (Empidonax flaviventris), and Yellow Warbler (Setophaga petechia). In addition, Ruffed Grouse often use alder stands as drumming sites, selecting a log with good visibility around them. It’s common to find nests and broods in alder thickets on upland sites.
Speckled Alder is found in wet sandy or gravelly soils, usually along streams and rivers, but also along edges of ponds and in swamps and wetlands. It is only found in open sunny areas, being unable to compete in dense shade, and can slowly spread via runners from its extensive spreading root system.
In New York, Speckled Alder is a characteristic plant found in these ecological communities:
In 2012, the United Nations General Assembly proclaimed March 21st as the International Day of Forests to celebrate and raise awareness of the importance of all types of forests.
Worldwide, there are three general types of forest that exist:
(1) temperate forests are generally found in North America, Europe, and East Asia;
Experts estimate that, together, these forests cover approximately one-third of the Earth’s surface.
In New York, we experience a notably greater extent of forest cover on our landscape. Here, forests cover 18.6 million acres, or 61% of land area. The most common type (53%) is deciduous forest comprised of species of maple, beech, and birch.
For more information regarding the importance of forests to us humans, please read:
While there are a number of forests throughout our area, please consider a visit to this local forest: Mooney Carrese Forest.
The 78-acre Mooney Carrese Forest comprises more than half of the 141-acre Veterans Memorial Park, which is located at 697 MacElroy Road in the Town of Clifton Park. Purchased in the spring of 2013 from Kathleen and Arnold Carrese and their family, the forest is located in the southwest portion of the park. Tributaries to the Cooley Kill traverse the site.
Panoramic view of water feature along trail through Mooney Carrese Forest
The addition of this forest offers visitors an undulating hike crossing small watercourses past wetlands as well as mature stands of Eastern Hemlock (Tsuga canadensis) and Eastern White Pine (Pinus strobus) in the uplands.
Is it no wonder that forests offer a beautiful setting in which to relax?
As I was reminded on one of my late winter visits here, our forests also offer places for you to contemplate the many wonders of nature. Such as, what is going on in this photo? In other words, why is a Yellow Birch (Betula alleghaniensis) growing out of the trunk of this Eastern White Pine?!? (Feel free to leave a message below to share your pontifications as to “how” this happened.)
Yellow Birch sapling growing out of hollowed branch bole of Eastern White Pine
The combined properties comprising Veterans Memorial Park offer great habitat for White-tailed Deer (Odocoileus virginianus), small mammals, amphibians, and a diversity of birds, including Wild Turkey (Meleagris gallopavo). For example, the Illustrated Checklist of Birds Observed is an ongoing compilation of bird species that have been observed at Veterans Memorial Park.
Notice the arc of the sun across the sky each day. You’ll find that it’s shifting toward the north. Responding to the change in daylight, birds and butterflies are migrating back northward, too, along with the path of the sun.
If you will be visiting some of our local nature preserves, parks, and trails, I hope you will consider downloading my wildflower field guides for those destinations. I have recently updated my wildflower field guide for Veterans Memorial Park; you can view or download it here. I hope it helps you learn about wildflowers that you may encounter during your future visits.
Beaked Hazelnut (Corylus cornuta) – typically begins blooming in MarchEmerging leaves of False Hellebore (Veratrum viride)Carolina Spring Beauty (Claytonia caroliniana) – typically begins blooming in mid-AprilCommon Shadbush (Amelanchier arborea) begins blooming in mid- to late April, before its own leaves unfurl.
Consider these activities as part of your adventures this spring –
The Great North American Total Eclipse: The Science, the History, and Why You Should Get Your Butt to Totality (If Possible) (3/23/2024 @ 11:30am; Registration required: Call 518-872-0800)
I’m happy to announce the availability of an expanded second edition of the wildflower field guide for the Veterans Memorial Park (Town of Clifton Park).
This guide is available as a FREE download (in Microsoft PowerPoint Slide Show format) from the Wildflower Field Guides page of this blog. You’ll also find a Quick Read bar code if you wish to easily download the field guide onto a mobile device of your choice – that will enable you to use it as you walk along this trail network.
As are all of my field guides, this one is arranged according to the chronological order of when the selected species begin blooming. Starting in March and continuing into October, the guide features full color photographs of the noted species, including –
From the Veterans Memorial Park guide:
The guide also includes trail maps as well as other information about each plant’s key characteristics to help you identify it. For those species deemed culturally significant, there are links to other online resources with additional information.
For those of you who live near this park or who frequent it, I hope this expanded wildflower field guide adds to the enjoyment of your future visits.
Last Thursday, I took the opportunity to stroll along the Uncle Sam Rail Trail (part of the Uncle Sam Bikeway) in the City of Troy to continue the wildflower inventory that I’m now conducting along it. Much to my surprise, I found a couple of very early blooming specimens: Hairy Bittercress (Cardamine hirsuta) and Whitlow Grass (Draba verna).
Earlier today, I found these additional early bloomers while out and about along a couple of other local trails –
Maria Sibylla Merian was a naturalist and illustrator who was especially influential in shaping our understanding of the metamorphosis of the butterfly and laid the foundation for modern entomology in the 1700s with her book Metamorphosis insectorum Surinamensium.
Butterflies belong to the Order Lepidoptera; Lepidoptera is derived from the Greek lepis meaning “scale” and pteron meaning “wing.” Butterflies have broad wings that are covered with minute overlapping scales and are usually brightly colored. Gaze into a Blue Morpho Butterfly wing.
Suggestions for what to do today:
Visit Dancing Wings Butterfly Garden in Rochester or the Davis Family Butterfly Vivarium in New York City to walk among hundreds of brilliantly colored, free-flying tropical and native butterflies. Or, perhaps visit the Niagara Parks Butterfly Conservatory in Niagara Falls, Ontario, featuring over 2,000 vibrantly colored butterflies fluttering freely throughout winding pathways adorned with lush vegetation and trickling waterfalls.
Watch the documentary Wings of Life, directed by Louie Schwartzberg and narrated by Meryl Streep. It features a super-close look at the world of butterflies (and other pollinators) and their collaboration with flowers on which fully one third of the world’s life-sustaining food supply for us humans depends.
Make plans to establish your own butterfly-friendly garden:
Choosing the right location – sunlight is the key. Begin by finding a garden location that receives at least six to eight hours of sunlight, but also one that is sheltered from the wind. Your spot should also provide nighttime hiding places for butterflies such as small trees or large shrubs, and places for them to attach while in their chrysalis.
Soil is essential; understand what your plants require and, if necessary, supplement your site by adding topsoil or soil amendments.
Choose a variety of native species that will feed larvae as well as adults. Host plants are food to larvae, while nectar plants are important food sources for adults. In addition, select a variety of species that will bloom throughout as much of the growing season as possible; try to offer a continuously overlapping series of blooming plants that extends into autumn so as to offer fuel to those who migrate.
Placement of your selected plants – clump them by species and color to make them easier to see to the visiting butterflies. Primarily, butterflies are attracted to purple, yellow, white, and orange flowers.
Provide a puddling station, which is an area, or simply a dish, filled with rocks for butterflies to perch on and sand or dirt that is kept moist so that butterflies can drink and absorb some much-needed nutrients. Butterflies require essential minerals and salts that are found in soil and water, but not in nectar.
These winged creatures have long been viewed as otherworldly messengers and heralds of good fortune and joy. As masters of metamorphosis, butterflies are significant symbols of transformation, freedom, and rebirth. The color displayed by a butterfly also has symbolic meaning (SOURCE: https://aimeeschreiber.com/blogs/news/butterfly-symbolism#):
Black: mystery, night, potential death, elegance, shadow and protection
Blue: truth, creativity, communication, trust, air, and faith
Green: balance, fertility, love, healing, and life
Indigo: wisdom, intuition, inspiration, authority, and honesty
Orange: youth, curiosity, pleasure, happiness, creativity, and sexuality
Red: courage, passion, the life-death-life cycle, fire, and survival
Violet: spirituality, quietness, dreams, awakening, royalty, and creativity
White: purity, unity, innocence, peace, day and simplicity
Yellow: clarity, confidence, power, enlightenment, energy, and humility
Butterflies have been part of human culture the world over. American Indians considered butterflies a positive symbol and believed they should typically be thought of as comforting.
The Blackfoot believe butterflies bring dreams and inspiration.
The Cherokee, Hopi and Shoshone perform a ceremonial dance called the Butterfly Dance where women use brightly colored shawls to represent butterfly wings. The dance tells the story of tragedy and the eventual rebirth of happiness, as a woman who has lost her love travels the earth with her wings packed away, until her sorrow was finally healed and she was reborn. View the butterfly dance by Hopi dancers.
Butterflies are some of the wildlife spirits that appear in Hopi figurines and pottery, symbolizing transformation and balance.
To the Lakota, butterfly is a symbol of new beginnings, transition and beauty.
The Ojibwe culture believes that butterflies roam the world bringing wonder and laughter to children.
Butterflies have also inspired artists of all kinds over the centuries. View a painting by Vincent van Gogh featuring butterflies. Listen to songs inspired by butterflies. In closing, read a poem about these winged beauties.
Flowering plants have been around for at least 150 million years. National Plant a Flower Day encourages people to plant a flower in honor of the vital role flowers play in our ecosystems, history, religion, traditions and inspiration.
Locally near Clifton Park, the likely last day for a spring frost is May 15. While it is obviously much too soon to plant any flowers outdoors at this time, it would be OK to start seeds indoors that have gone through cold moist stratification and that you intend to keep indoors in small containers until such time that the seedlings are an appropriate size for transplanting after May 15. For other localities, view first and last frost dates by zipcode, provided by The National Gardening Association.
To begin plants indoors after cold/moist stratification of your harvested seeds, press the seeds into the surface of your potting mix. Keep the soil of each container moist until germination occurs. They should not be allowed to dry out. Any time after May 15, you may then transplant the contents of each container into the spots you’ve selected to establish these plants.
What native wildflowers might you want to start indoors at this time in readiness for transplanting them outdoors after mid-May? Here’s a few suggestions for your consideration.
Blue Vervain (Verbena hastata) can be found in moist meadows in floodplain woodlands, soggy thickets, fence rows, and along borders of rivers, ponds, marshes, ditches, and pastures. It is perfect for backyard ponds along pond edges. Once established, Blue Vervain spreads slowly through rhizomes and self-seeding. It begins blooming during the last week of June and continues for approximately six weeks. To learn more about this native wildflower, please view my prior post What Wildflower Begins Blooming This Week? (June week 4), published on 6/26/2021.
Seeds require 1-3 months of cold/moist stratification before planting
Once planted, seeds require 2-4 weeks to germinate
Seed-started plants will likely flower the year after sowing
Boneset (Eupatorium perfoliatum) is a native clump-forming perennial flower that commonly grows in wet soils of woods, prairies, and meadows. Consider using it in a rain garden or a woodland garden setting where the soil is constantly on the wet side. Boneset tolerates partial shade, but it will flower better if you give it full sun. While it will reseed readily if populations are large enough, Boneset mostly spreads via underground rhizomes. So do not plant it in a flower bed that will share space with other plants. It begins blooming during the third week of July.
Seeds require 1-2 months of cold/moist stratification before planting
Once planted, seeds require 1-2 weeks to germinate
Seed-started plants will likely flower 2-3 years after sowing
Enchanter’s Nightshade (Circaea canadensis) can be found in woodland settings with dappled sunlight or medium shade. It can be used in a woodland setting, naturalized area, or shady garden. Once established, it spreads by both seed and rhizomes, often creating small colonies. It begins blooming during the last week of June and continues for approximately one month.
Seeds require 3-5 months of cold/moist stratification before planting
Once planted, seeds require 3-4 weeks to germinate
Seed-started plants will likely flower 2-3 years after sowing
Hairy Beardtongue (Penstemon hirsutus) can be found in forests, glades, forest margins, rocky woodlands, and along roadsides. It is great for borders, cottage gardens, rock gardens, and pollinator gardens. Once established, Hairy Beardtongue will readily self-sow. It begins blooming during the second week of June and continues for approximately 4-6 weeks.
Seeds require 1-2 months of cold/moist stratification before planting
Once planted, seeds require 10-21 days to germinate
Seed-started plants will likely flower 2-3 years after sowing
Hairy White Oldfield Aster (Symphyotrichum pilosum) is found on forest edges, meadows, prairies, or open woodlands and readily pops up in vacant lots, fields, ditches, or anywhere there is bare soil via aggressive self-seeding. In this manner it is not always a great choice for formal flowerbeds, but can be a great addition to wildflower meadows or perennial borders to add some late-season blooms. It begins blooming during the first week of August and continues for approximately six weeks.
Seeds require 3-4 months of cold/moist stratification before planting
Once planted, seeds require 2 weeks to germinate
Seed-started plants may flower in the year that they are sown
Heart-leaved Aster (Symphyotrichum cordifolium) is commonly found in woodlands, meadows, or along stream banks. It can be weedy as it self-seeds very easily and creeps slowly by rhizome as well. In this manner it is not always a great choice for formal flowerbeds, but can be perfect for extending color and interest in the woodland shade garden to add some late-season blooms. It begins blooming during the second week of August and continues for approximately four weeks.
Seeds require 2 months of cold/moist stratification before planting
Once planted, seeds require about 2 weeks to germinate
Seed-started plants may flower in the year that they are sown
Mad-dog Skullcap (Scutellaria lateriflora var. grohii) can be found in moist meadows, openings in floodplain woodlands, soggy thickets, swamps, bogs, seeps and springs, and edges of vernal pools and ponds. It can be used in a woodland garden with a sunny edge and dappled shade and for moist to wet low spots such as stream or pond margins and marshy areas. Once established, it spreads by both seed and rhizomes, often creating small colonies. It begins blooming during the first week of July and continues for approximately 1.5-2 months. To learn more about this native wildflower, please view my prior post What Wildflower Begins Blooming This Week? (July week 1), published on 7/3/2021.
Seeds require 6-8 weeks of cold/moist stratification before planting
Once planted, seeds require about 2 weeks to germinate
Seed-started plants will likely flower 2-3 years after sowing
Tall Goldenrod (Solidago altissima ssp. altissima) is found on old fields, pastures, road banks, and disturbed soil; it clearly does best in dry open areas. Tall Goldenrod often forms dense patches in successional fields and is one of our most common goldenrods. Consider using it in large borders or in a managed meadow. Tall Goldenrod develops many creeping rhizomes that cause the plant to cluster; therefore, it is not recommended for smaller planting areas. It begins blooming during the second week of August.
Seeds require 2 months of cold/moist stratification before planting
Once planted, seeds require about 2 weeks to germinate
Seed-started plants may flower in the year that they are sown
Turtlehead (Chelone glabra) can be found in swamps, marshes, ditches, and wet thickets. This perennial herbaceous plant makes an excellent choice for wetland plantings or the edges of ponds or streams. Once established, Turtlehead spreads slowly over time from short rhizomes and self-seeding. It begins blooming during the first week of September and continues for approximately four weeks. To learn more about this native wildflower, please view my prior post What Wildflower Begins Blooming This Week? (September week 1), published on 9/4/2021.
Seeds require 3-4 months of cold/moist stratification before planting
Once planted, seeds require 3-5 weeks to germinate
Seed-started plants will likely flower two years after sowing
FYI:
Cornell Cooperative Extension Service is conducting a quarterly Sustainable Landscapes Lunch & Learn series in 2024 to promote climate change conscious and regionally-adapted skills for ecological gardening. It focuses on areas of soil health, water management, herbs and vegetables, ornamental perennials, edible perennials, woody plants, sustainable lawn care, and habitat for birds and beneficial insects. Each quarterly webinar will feature three lightning talks on the essential skills for that season.
March 20th, 12:00 – 1:30 pm: Spring Ecological Gardening Practices – Register Here
June 26th, 12:00 – 1:30 pm: Summer Ecological Gardening Practices – Register Here
September 18th, 12:00 – 1:30 pm: Fall Ecological Gardening Practices – Register Here
December 18th, 12:00 – 1:30 pm: Winter Ecological Gardening Practices – Register Here
National Invasive Species Awareness Week, which concludes today, is a national event to raise awareness about invasive species, the threats that they pose, and what can be done to prevent their spread. It is sponsored by the North American Invasive Species Management Association (NAISMA), which supports local, state, tribal, federal, regional, and national organizations to raise awareness of local invasive species concerns to elected officials, agency leadership, and the public.
The term “invasive” is used for non-native species of plants and animals that grow and reproduce rapidly, displace native species, and cause major disturbance to the areas in which they are present. However, invasive species also include non-native pathogens. Invasive species can be found on land or in water. Once they become established in areas outside their normal habitat range, they are capable of causing severe damage, including harming the economy, the environment, or human health.
This week, we’ve explored:
a brief history of the arrival of invasive species,
how invasive species spread,
why they are harmful,
types of invasive species (animals, insects, pathogens, and plants),
how invading species are now being detected, and
ongoing research efforts about invasive species.
Today, we’ll conclude this week-long series of articles about invasive species by exploring various methods employed to control or eradicate invasive species.
The most economical and safest way to manage invasive species is by prevention. Early detection and rapid response of invasive species is much more effective than trying to control a widespread infestation.
Once invasive species are discovered, a variety of methods are used for their control and management. Those include:
biological,
chemical,
cultural,
manual, and
mechanical.
You can also use a combination of control methods for an integrated approach using Integrated Pest Management (IPM). The IPM approach does not refer to a specific management technique, rather it uses a multi-strategic approach with compatible techniques and methods to maintain pest populations below levels that will cause significant economic and environmental damage.
Biologicalcontrol is the intentional manipulation of biocontrol agents by humans for the purpose of reducing the population of a targeted invasive species. Agents selected and typically used are the natural enemies of the targeted species and may involve different organisms, such as insects, mites, nematodes, and pathogens. In North America, most biological control agents of invasive plants are plant-feeding insects, of which beetles, flies, and moths are among the most commonly used. Biological control agents also include imported fish, and other organisms that eat or infect the targeted species. Further, biological control may involve the release of genetically modified organisms.
Genetic biocontrol can be defined as the release of organisms with genetic methods designed to disrupt the reproduction of invasive populations. Different approaches of genetic biocontrol for invasive species include:
sterile insect technique,
YY males (trojan Y chromosome),
trojan female technique, and
gene drive.
Sterile insect technique produces large numbers of sterile individuals that are then distributed within a target population in order to suppress reproduction. YY males (trojan Y chromosome) reverses the sex of a captive population of males via use of sex hormones to produce genetically all-YY males whose progeny are then released into a target wild population where they increase in the population over time at the expense of females until females are eventually eliminated, causing the population to collapse. Trojan female technique involves the steady release of modified females that carry mitochondrial DNA (mtDNA) mutations that cause reductions to male, but not female, fertility, and, over time, causes the population to collapse. Gene drive is gene editing technology to introduce desired genetic traits (such as genes designed to reduce populations by skewing sex ratios) into a captive population that, when they are released, will be inherited by the targeted wild population. (SOURCE: Teem John L., Alphey Luke, Descamps Sarah, Edgington Matt P., Edwards Owain, Gemmell Neil, Harvey-Samuel Tim, Melnick Rachel L., Oh Kevin P., Piaggio Antoinette J., Saah J. Royden, Schill Dan, Thomas Paul, Smith Trevor, Roberts Andrew, Genetic Biocontrol for Invasive Species, Frontiers in Bioengineering and Biotechnology, 25 May 2020, Volume 8, https://doi.org/10.3389/fbioe.2020.00452)
The aim of biological control is not to eradicate the targeted invasive species, but to control it in a way that it becomes manageable. In other words, the method uses nature’s own mechanisms to help ensure equilibrium within the population of the invading species.
Biological control involves much research and testing to make sure the prey targets only the invasive species intended. Successful examples include:
Chemicalcontrol includes the use of herbicides, fungicides, and insecticides. Although chemical use can be very effective, they can be dangerous to other species or to the ecosystem in general. Pesticides must always be applied in accordance with the label. Please refer to How to Read a Pesticide Product Label Infographic.
A systemic herbicide is applied to and absorbed by the leaves or other portions of a plant so that it is translocated throughout the plant, including the roots. This generally results in the death of the entire plant, rather than just the portions directly treated with the herbicide. Contrastingly, a contact herbicide is a chemical that kills only the portion of the plant to which it is applied. Herbicides of this type do not kill the roots of a plant, but may be effective in controlling annual weeds or seedlings that do not have a well-developed root system.
Most of the commonly known invasive plants can be treated using only two herbicides: glyphosate and triclopyr. Glyphosate (the active ingredient in Roundup™ and Rodeo™) is non-selective, meaning it kills everything it contacts. Triclopyr (the active ingredient in Brush-BGone™ and Garlon™) is selective and does not injure monocots (grasses, orchids, lilies, etc.).
Herbicides are applied by one of the following methods:
Foliar mist (or “spraying”) is one of the most common techniques of herbicide application. This technique uses a mist blower or sprayer to apply a low concentration of herbicide onto the surface of living leaves where it is absorbed into the plant. This technique is best used when the foliage of the plant is relatively accessible, and wherever the target invasive species has effectively become a monoculture with a high density of stems. Conversely, individual invasive plants may be easily targeted by foliar application with a small handheld spray bottle. Large infestations will likely require a backpack sprayer or a sprayer mounted on an all-terrain vehicle that can travel across the treatment site. Spraying works best when plants are actively growing, the mist completely wets the leaves, and the spraying is conducted on a day with little wind and no rain in the forecast.
Basal bark treatment involves applying a low volume of herbicide solution sprayed at the base of the stem of a woody plant. This is a common technique used on small- or medium-sized shrubs and trees where overhead foliage is not easily accessible. The herbicide solution includes a surfactant or an oil carrier that allows for the herbicide to be absorbed through the bark into the plant. This technique can be used during the growing season and well into the fall or early winter. Basal bark treatment is best for small- and medium-sized stems.
Cut-stem treatment involves cutting the woody plant stem completely or partially and applying a more concentrated herbicide solution to the freshly exposed wood. The herbicide solution is painted on the cut stump using a brush or sponge, or it is injected using a special tool. Herbicides should be applied to the exposed wood immediately following cutting so to avoid dry-out before treatment. A colored dye is often added to the herbicide solution to track which stems have been treated. Cut-stem treatments are most effective when applied in late summer and fall and they are best for large stems.
Successful examples of chemical control of invasive species include:
Culturalcontrol measures are aimed at changing human behavior to address the issue of spreading invasives — using opportunities to educate people about practices to increase awareness about how to prevent the spread of invasives. Cultural practices include mulching, soil solarization with plastic film, thermal weed control (e.g., flaming, hot water, and steam), prescribed burning, water manipulation, and prescribed grazing using cattle, goats, horses, and sheep.
Successful examples of cultural control of invasive species include:
Manual control involves physical activities such as hand-pulling, digging, flooding, de-watering, dredging, mulching, manual destruction or removal of nests, egg masses, or other life stages, or shading to control invasive plants. Methods generally include the removal or destruction of an invasive species by hand. Manual control is often labor-intensive, costly, and may only provide temporary relief.
Successful examples of manual control of invasive species include:
Mechanicalcontrol techniques include mowing, hoeing, tilling, girdling, chopping, and constructing barriers using tools or machines to “harvest” invasive plants by removing and collecting them, and transporting elsewhere and allowing them to decompose in place. Mechanical treatments complement chemical control and, especially when combined with chemical control, can be very effective and efficient in reducing the presence of invasive species.
Successful examples of mechanical control of invasive species include:
Integrated Pest Management (IPM) is an ecosystem-based strategy and a process for planning and managing the land that focuses on long-term prevention of invasive species or their damage through a combination of techniques. A key principle is that it is necessary to take action only when infestations warrant it, not as a routine measure. This might even require changing your activities on your own property or, if on public lands, changing the activities of visitors, such as restricting the use of recreational vehicles, to prevent disturbance that often leads to invasive plant invasion. Within an IPM framework, pesticides are used only after monitoring indicates they are needed according to established guidelines, and treatments are made with the goal of removing only the target organism. Pesticides are then selected and applied in a manner that minimizes risks to human health, beneficial and nontarget organisms, and the environment.
The principles of IPM include:
identify invasive species, their hosts, and beneficial organisms also present within the treatment area before taking action,
establish monitoring guidelines for each invasive species,
evaluate and implement control tactics, and
monitor, evaluate, and document the results.
Successful examples of an IPM approach to the control of invasive species include:
I hope this series of posts over this past week has helped you to learn more about invasive species and that they will inspire you to join efforts to help reduce their impacts. Thank you!
Curious By Nature 
