Posts Tagged Asiatic Hawksbeard

Invasive Exotic Species: The Ongoing Battle

Chinese wisteria strangling a forest edge.

Chinese wisteria strangling a forest edge.

If you’ve read this blog much, you’ve read about my feelings regarding invasive exotic species. These plants/animals/diseases are not native to the region, which means they have no natural predators. They move in, spread aggressively, and permanently alter the composition and health of our native forests.

The problem is world-wide. Ecologists everywhere consider invasive species to be the second biggest threat to the remaining biodiversity on our planet. Only outright habitat destruction due to urbanization poses a greater threat to the health of our ecosystems.

Of the alien plant invaders I hate the most on my five acres of North Carolina piedmont, I think the Most Evil prize must go to Japanese Stiltgrass (Microstegium vimineum). This invading grass has transformed creeks and wetlands throughout my region into big ugly messes, and the wildflowers and ferns that once flourished there are disappearing rapidly.

Winter-killed Microstegium vimineum still manages to overwhelm a native holly along the creek.

Winter-killed Microstegium vimineum still manages to overwhelm a native holly along the creek.

Number Two on my alien invader hate list is Japanese Honeysuckle (Lonicera japonica). Except during the coldest of winters, this evil vine remains green all year. Like Chinese Wisteria, Japanese Honeysuckle spreads from tree to tree in our forests, creating a dense tangle of vegetation that impairs the health of trees and provides access highways for predators of our native birds attempting to nest in the trees.

This tangle of Japanese Honeysuckle among the trees makes it easy for snakes, raccoons, and other predators to raid bird nests.

This tangle of Japanese Honeysuckle among the trees makes it easy for snakes, raccoons, and other predators to raid bird nests.

A lot of folks don’t realize that English Ivy is also invading our native forests. Like Japanese Honeysuckle, English Ivy produces berries beloved by birds. They spread the seeds through our forests, and the evergreen ivy starts its takeover. The weight of these non-native vines on our native trees causes them to be more easily pulled down by strong winds and ice storms. And from a purely aesthetic point of view, vines strangling forests are quite ugly.

A native dogwood being devoured by invading English Ivy.

A native dogwood being devoured by invading English Ivy.

My yard is also plagued by one of the invading species of Elaeagnus. More of a problem in piedmont uplands than floodplains, I’m finding it all over my yard now, thanks to bird-aided seed deposition.

The flowers of Elaeagnus are suffocatingly sweet.

The flowers of Elaeagnus are suffocatingly sweet.

Much scarier to me are invading evergreen privet shrubs on my floodplain. I see near-solid coverage of this shrub in wet woodlands throughout my region. They outcompete every native plant on the forest floor.

I am always on the lookout for invading privet. They pop up everywhere thanks to the birds that love their fruits.

I am always on the lookout for invading privet. They pop up everywhere thanks to the birds that love their fruits.

The newest invader on my “I hate it!” list is Asiatic Hawksbeard (Youngia japonica). This astonishingly aggressive low-growing plant is outcompeting even the crabgrass in my lawn! Wonder Spouse is planning an attack with a propane-powered weeder that burns the aggressors into cinders. I don’t want to think about what happens if that plan doesn’t work.

Terrifyingly invasive Asiatic Hawksbeard

Terrifyingly invasive Asiatic Hawksbeard

Under the “misery loves company” heading, I’m not alone in my battle against invading exotic species. Every government agency charged with protecting our native wild lands and animals is involved in this fight. Anyone caring for a park, farming, growing timber, or any other related activity is battling invasive species perpetually.

If you live in North Carolina and you have the time and discretionary funds to do so, you might want to attend the North Carolina Invasive Plant Council’s (NCICP) upcoming meeting on Feb. 11-12. They hold the meetings in different parts of the state each year. This year, the meeting is in Asheboro, NC at the NC Zoo. This year’s presentation topics include:

  • Invasive plant control in Mecklenburg County parks
  • Monitoring and mapping invasive insects and pathogens
  • Weed bio-control within a regulatory agency
  • Birds and invasive plant dispersal
  • Invasive plant challenges facing the Uwharries
  • Invasive aquatic vegetation and arteriovenous malformation disease
  • Invasive plants knocking at our door
  • Weed identification workshop

A field trip on the second afternoon will feature the NC Zoo’s greenhouse and composting operations, as well as demonstrations of how they handle invasive species on their grounds.

I’ve been to a number of these meetings, and I always learn much. For example, it was at one of these meetings that I learned about the Weed Wrench, still Wonder Spouse’s favorite weed eradication weapon.

I’m planning to attend this year, and I’ll report the highlights here. If you live in another southeastern state, consider contacting and joining that state’s chapter of the Southeast Exotic Pest Plant Council. I checked the links to each state, and it looks like the Alabama, Florida, and North Carolina chapters are the most active, holding annual meetings. If you live in Georgia, Kentucky, Mississippi, or South Carolina, I would encourage you to contact those chapters through the above link and ask them why their site is inactive. I can promise you it is not because they aren’t fighting invasive alien species in those states too.

If we stand any chance at all of preserving healthy native ecosystems in our parks, national forests, not to mention our own back yards, we all need to know as much as we can about invasive alien species. Forget about invaders from outer space. The invaders we need to worry about are already here.

2014 is the Year of the Lepidoptera!

To end on a happier note, I thought I’d let my fellow North Carolinians know that our state park system has decided to highlight our native butterflies and moths this year. All of our NC parks will be offering walks and family-focused events throughout the year that will educate folks about these important insects. To find a list of events near you, go here.

 

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For Earth Day: Love the natives; hate the invaders.

A new (for us) extraordinary native find on our floodplain yesterday.

A new (for us) and extraordinary native find on our floodplain yesterday.

I’m reasonably certain that’s a Spring Beauty (Claytonia virginica). This early-blooming spring ephemeral wildflower usually starts blooming just a day or two before the American trout-lilies in a moist woodland at the NC Botanical Garden in Chapel Hill. I’ve always thought them to be exquisitely delicate and lovely, and they were on my “Add Someday” list for our five acres of Piedmont chaos. No longer.

Yesterday, Wonder Spouse and I stumbled across two tiny blooming specimens in the middle of our currently moist floodplain. We haven’t mowed there yet, because we’re still picking up fallen limbs from winter storms, which is probably why it managed to push out flowers in time for us to notice. The Spring Beauties at the NC Botanical Garden grow in what becomes deep shade as the floodplain canopy trees above them leaf out. Our volunteers are in a sunnier locale, near a large pine, perhaps enough to give them afternoon summer shade. From this difference, I conclude that Spring Beauties require moisture more than shade.

Our volunteers likely found their way via floodwaters from our little creek, which is only about ten feet from their growing site, in an area that overflows whenever the creek waters escape their banks. We could not be happier to have this native join us: another native to love.

Wonder Spouse and I spent several hours wandering the floodplain/wetland habitats of our yard yesterday, because this is the time of year when their health is demonstrated by the ecological diversity of the beautiful native plants that thrive in the muck. Indeed, there is much to love in a healthy native wetland. There’s also much to worry about: invaders. Non-native, alien species remain the number two threat to healthy native environments world-wide (after outright destruction), and in my yard, we battle invaders constantly.

From Beauties to Bullies

Some battles are nearly hopeless. Japanese Honeysuckle and Japanese Stiltgrass are so aggressively pervasive in our North Carolina woodlands and backyards that the best most of us can do is to try to keep them out of selected areas — a favorite flowerbed perhaps, or a beloved tree, in the case of Japanese Honeysuckle.

Battles Still Worth Fighting

In my wetland/floodplain areas, the invader we are still fighting — so far, successfully <knock wood> is Chinese privet. This evergreen, common hedge shrub of older homes produces blue-purple berries that birds adore. They distribute seeds everywhere, but the privets are most dangerous to floodplain/wetland environments. In some areas in eastern North Carolina, the understory composition of vast acres of wetlands has been completely overtaken by invading privet. Because these non-natives are evergreen, they outcompete wildflowers, shrubs, and tree seedlings for light and other resources. Eastern North Carolina wetlands are becoming biological deserts, consisting of nothing but privet beneath canopy trees. When those trees die, no seedling trees will replace them, because they can’t compete successfully with privet. Eventually, our eastern wetland landscape will consist of miles and miles of nothing but privet.

Plant invaders are overlooked by most folks, because their progress is slower than, say, invading Emerald Ash Borers or Sudden Oak Death. To the untrained eye, green is green. But native animals and plants know how critical the differences are. If you love your southeastern Piedmont landscape, you should know too.

Whenever Wonder Spouse and I walk around our yard, we keep a sharp eye out for Chinese privets (Ligustrum sinense). Seedlings appear constantly, typically beneath trees, where birds deposit the seeds after feasting on privet fruits elsewhere. Yesterday, we spotted several larger shrubs that we had somehow overlooked previously. Greens blend together, and in crowded thicket areas (left for animal nesting habitat), a privet sometimes escapes our notice — for a while.  I am especially vigilant in my hunt for this species in my wetland and along the edges of my creek. These areas are most vulnerable to this devastating invader.

While hunting privet yesterday, I was disturbed to discover that some of the Autumn Olives (Elaeagnus umbellata) invading the top of our hill have made it to the floodplain and wetlands. This pernicious invader has taken over many acres of upland environments, such as ridge tops, in my part of the southeastern Piedmont. This species and its close cousins (E. angustifolia and E. pungens) are all non-native shrub species. All are very bad news for the local environment, despite the berries that birds eat with gusto.

Wonder Spouse grabbed his trusty Weed Wrench and went to work on the invading Elaeagnus shrubs, pulling out long-rooted invaders from mucky ground, accompanied by a rather satisfying sucking sound.

Note the flowers just opening on this newly wrenched specimen.

Newly wrenched.

Note the flowers just opening on this one:

Their perfume is cloyingly sweet -- nausea-inducing, if you ask me.

Their perfume is cloyingly sweet — nausea-inducing, if you ask me.

This was a larger one that put up considerable resistance before Wonder Spouse prevailed:

Die, monster, die!

Die, monster, die!

A New Enemy

And, there’s more bad news for my little patch of Piedmont: Asiatic Hawksbeard (Youngia japonica). This relatively recent annual invader was introduced by the nursery trade. It was probably inevitable, given the number of plants from nurseries that I’ve added over the decades, that this horrifyingly aggressive invader would appear on our property.

It may not look like much, but...

It may not look like much, but…

To the casual eye, the basal rosette of jagged leaves of Youngia looks quite like that of a Dandelion. But if you look a little more closely, the dangerous differences become evident. It sends up clusters of small yellow flowers on bloom stalks. Dandelions only produce one, much larger yellow flower per stalk. Seeds of Asiatic Hawksbeard look somewhat like those of a Dandelion; they are both attached to white tufts that allow them to float far on breezes. But Hawskbeard seed tufts, like its flowers, are much smaller — and uglier — than those of Dandelions.

Compare this relatively polite Dandelion ...

Compare this relatively polite Dandelion …

With the Hawksbeards on either side of this Dandelion. Yes, they are even crowding out the Dandelions!

With the Hawksbeards on either side of this Dandelion. Yes, they are even crowding out the Dandelions!

I know you’re thinking this is just one more lawn weed, right? Not really. Unlike our common non-native weeds — Dandelion, Henbit, Chickweed, Lambs Quarters — Asiatic Hawksbeard spreads much, much more aggressively. Its basal rosettes are dangerously easy to overlook, and now the experts tell me that they are moving into our dwindling natural areas. In these diminishing patches of native forest, Asiastic Hawksbeard is joining Japanese Stiltgrass, Japanese Honeysuckle, and larger invaders in displacing native wildflowers and other small native plants. Every new invading plant means more competition for food, light, and water for our natives. With no natural predators to slow them down here, their eventual takeover seems a near certainty.

Asiatic Hawksbeard has a taproot similar to that of a Dandelion, and if you don’t get it all when you pull it, the plant will regenerate. Also, you can’t just toss pulled Hawksbeards onto your compost pile. Flowers and even nearly-open flower buds finish their cycle and release seeds into the environment even after they’re pulled. Knowing this, I spent many, many hours last year carefully digging out this new invader from my yard wherever I found it. Every plant went immediately into a trash bag, which I tied and left in the hot sun to fry before adding it to my trash can. Despite my efforts, the Youngia is much more pervasive now that it was last year. And I’m seeing it in all parts of my yard now, whereas, last year, it was confined to only certain areas. The basal rosettes have a distinctive yellow cast, and the leaves are slightly fuzzy. I’ve become quite adept at spotting them. Next winter, whenever we spot one, Wonder Spouse and I are planning to resort to treating them with Round-up. Wonder Spouse and I are ridiculously outnumbered, and this is a war we don’t want to lose.

Reasons to Keep Fighting

And there is so very much to lose. On this Earth Day, let me leave you with a few positive images from our still-healthy wetland, where the wildflowers and other plants are wakening to warming weather with enthusiasm for another growing season.

Our ever-widening stand of Mayapples is blooming profusely.

Our ever-widening stand of Mayapples is blooming profusely.

Cinnamon ferns sport spice-colored fruiting fronds while nearby Atamasco Lilies begin to flaunt flowers.

Cinnamon ferns sport spice-colored fruiting fronds while nearby Atamasco Lilies begin to flaunt flowers.

Jack-in-the-Pulpits are preaching to all who will listen about the importance of healthy wetlands.

Jack-in-the-Pulpits preach to all who will listen about the importance of healthy wetlands.

On this Earth Day — and every day — I will continue to love the diverse and beautiful native species that bless my property. And I will battle non-native invaders as long as I can breathe. Clean water and air can’t exist without the help of healthy native environments — especially wetlands. Do your part today and every day by eradicating invaders in your yard. To learn more about invaders in Southeastern North America, start here.

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