Second year in bloom

First year rosette

Spotted Knapweed - AKA Centaurea maculosa, Centaurea steobe

This is a plant I am a bit sorry to see on the outlaw list.  I am sure you have seen it in town and growing in patches along the highways.  The plant produces lots of pretty pink flowers in July often in areas you wouldn't believe anything could possibly grow.  It often frequents neglected areas with sandy gravelly soil, for example our town transfer station, along railroad tracks, sandy roadside ditches, vacant lots, etc.  I used to believe this plant, with its attractive summer blooms, added an aspect of hope to sites otherwise devoid of beauty. At one point I actually thought about adding it to one of my gardens.  Fortunately, I did not.  With its aggressive growth habits, I definitely would have regretted it.  One really shouldn't move plants from the wild to one's own garden until it is known exactly what you are dealing with, or for that matter if it is even legal.  

Spotted knapweed, a member of the aster family, is native to Western, Central, and Eastern Europe where it along with other plants from the Centaurea genus, has an ancient history of medicinal use.  It is considered a biannual forming a short rosette of leaves in its first year.  During its second year it grows to a height of about two feet and produces flowers.  The flowers are a good source of pollen and nectar for our native bees as well as honeybees which are native to 

Europe imported here during the 1600's.  Interestingly honeybees when first introduced were referred to as White Man's flies by Native Americans.  Spotted knapweed is among several plants employed by beekeepers to increase honey yield.  While that may prove profitable in the near term, if invasive species are allowed to take over, the lack of variety of nectar and pollen throughout the season by native plants is guaranteed to have a negative effect on native bees as well as honeybees.  Spotted knapweed is an extremely prolific seeder, with a single healthy plant producing around 1000 seeds.  With that quantity of seed production this plant has the capacity of crowding out native plants, additionally it is yet another invasive plant with allelopathic properties, producing a chemical that discourages other plants from growing near it.  Fortunately, seed production is this plants primary means of spread.  When colonies are growing on sandy riverbanks the likelihood of erosion increases because of this plant's frail root system which does not hold the soil in place very well, especially during heavy water flows.  With its heavy seeding, if in a pasture setting, spotted knapweed has the capacity of rapidly taking over grazing areas providing less diverse food for wildlife and certain livestock.  

 How To Remove

Small colonies can be easily managed by hand pulling with help of a shovel or trowel.  The use of gloves is recommended as some may have a sensitivity to this plant.

Herbicides containing 2,4-D, Triclopyr, or Dicamba are also recommended.  To be most effective and prevent seed spread they should be applied during the time when the plant is in it budding stages, before flowers open.  Monitoring of the area and repeat application will be required as past fallen seeds remain viable for a number of years.

Biological Control

Sheep, goats and cattle will readily consume spotted knapweed in all its growing stages but especially when it is in its bolting stage, the period in mid-July when it begins to form buds and flowers. The plant has a nutrition profile similar to alfalfa when it is in its rosette stage with nutrition declining slightly when the plant is bolting. Repeated grazing will significantly reduce the presence of this invasive plant allowing for more diverse pasturage. 

Over the years several different insects have been introduced as a biological control for spotted knapweed.  Some target the flower or seed heads dramatically reducing the number of seeds the plant sets.  Other insects or their larvae damage the roots. Still others weaken plant by feeding on its leaves. The following list was taken from the USDA:

The sulfur knapweed moth (Agapeta zoegana) larvae feed within the plant's roots. The knapweed peacock fly (Chaetorellia acrolophi) larvae feed on the plant's seeds. The green clearwing fly (Terellia virens) larvae feed on seeds within flowerheads of spotted knapweed. The knapweed root weevil (Cyphocleonus achates) larvae feed within spotted knapweed roots. Larinus minutus, a seedhead weevil, larvae destroy spotted knapweed seed in the seedheads. Larinus obtusus, blunt knapweed flower weevil, larvae feed on seeds within the seedheads and adults feed on leaves. Urophora affinis and Urophora quadrifasciata are seedhead gall flies that are also used as biocontrol agents for spotted knapweeds. It is perfectly legal to move a plant that is infested with any of these insects to an area of plants not yet infested.

 

                                CYPRESS SPURGE AKA Euphorbia cyparissias

During the 1860's Cypress spurge was imported from Eurasia for its decorative appeal. Likely because of its low maintenance nature, it was frequently planted in graveyards, so much so that one of its common names is graveyard weed. Cypress spurge is a groundcover with fine narrow leaves growing in alternate pairs along the stem that eventually form whorls along the upper portion.  When in bloom, the plant is loaded with an abundance of small pretty yellow flower clusters giving it a very attractive appearance. Another of the plants characteristics is the milky substance that is exuded from the stem or root when either are broken.  This toxic lactic substance can cause contact dermatitis in some people. Originally intended as an ornamental groundcover, the plant readily escaped cultivation and has now achieved its present outlaw status. The plant is considered potentially toxic to horses and cattle, though most grazing animals will instinctively avoid it.  When I started one of my gardens, shortly after moving here, I noticed this volunteer plant growing along the back edge.  I welcomed it and encouraged it to grow.  Quickly realizing that it did not need any encouragement, my intentions changed, and I began trying to eradicate it.  It has been over 20 years now and I have yet to become successful in that endeavor.  The plant has a trailing rhizome type of root system that can reach up to ten feet.  The root readily breaks off as you pull it and new plants form from lateral buds all along the remaining root segments; so, it continues to grow in the back of my garden along the tree line right next to the poison ivy adding another level to my exasperation. As you can imagine the plants abundant flowers eventually produce abundant seeds, up to three seeds to a capsule, and to make matters even worse, the mature seed pods explode propelling the seeds up to 16 feet away!  Take my advice DO NOT ENCOURAGE THIS INVASIVE VINE!  As is true of all invasive non-native plants, the aggressive growth of Cypress spurge crowds out native species.  Because of the lactic substance exuded it is not considered a grazing plant, in fact this plant not considered beneficial for any of our native wildlife.

HOW TO REMOVE

If this plant is growing in your garden, you can attempt its eradication by pulling it. You can contain the spread this way but if you don't pull out the entire root the plant will continue to exist in your garden.  Though I have not had an issue with contact dermatitis, I suggest wearing gloves to prevent possible a possible occurrence from contact with the sap.  The most effective control method is to apply an herbicide such as glyphosate.  You will likely need to repeat application during the growing season.  If Cypress spurge is growing in your lawn or in a horse or cow pasture, the recommendation is repeated mowing every 21 days after the first bloom.  It is important to continue the 21 day mowing process as mowing encourages new growth.  If the plant is already in seed mow around it so as not to encourage further spread of the seed.  Eventually consistent mowing during the plant's growing season should deplete the plant of its growth energy.  Another herbicide you might consider is 2,4-D amine.  The first application should be at early bud stage.  A second application will be needed during the plant's growing season.  This can be a difficult plant to eradicate in a livestock pasture setting.

Biologic control

There are at least two insects that will help to limit growth of the plant.  The brown dot leafy spurge beetle Aphthona cyparissiae, and the black leafy spurge flea beetle Aphthona lacertosa.  These insects lay their eggs at the root base of the plants.  The larvae feed on the roots and the adult beetles feed on the foliage.  Actually, there have been 11 species of European insects released in North America to help control this plant.  It seems none have found the Cypress spurge in the back of my garden, at least not yet!

 

              Common Reed - Phragmites australis australis

This plant was unintentionally introduced from Europe in the late 1700's or early 1800's.  The seed likely hitched a ride either among ship's ballast, or from reeds used as protective packing material when fragile items were shipped. As with many invasives, the plant is not all bad. Most parts of the plant are edible with young shoots said to be similar in taste and texture to bamboo shoots.  If common reed is growing in a marsh, livestock will graze on it.  The plant can even be used as a construction material.  In parts of Europe this is one of the plants used for thatching roofs.  Additionally, the extensive root system is able to help filter out impurities from polluted water.  So, what is so bad about this plant?  Our native species of Phragmites called Phragmites australis americanus is diminutive in comparison. The native Phragmites, along with other native wetlands or bog plants, all of which are called helophytes, are rapidly being crowded out by the invasive behemoth Phragmites australis australis.  The invasive version, which has essentially conquered the world, has an incredibly aggressive growth pattern. It reaches an approximate height of 19 feet shading and crowding out our 6 1/2-foot native Phragmites, as well as any other native helophytes desiring an opportunity to grow.  Invasive common reed grows from seed as well as from rapidly spreading rhizomes (horizontal underground roots) and stolons (above ground horizontal shoots).  The rhizomes can grow 6 feet per year, so you can see how quickly Common Reed can spread forming a monoculture. You often see Invasive Common Reed growing in wetland habitats around ponds, drainage ditches, rivers, streams, and even in brackish water estuaries along Connecticut's beaches.  This plant is not terribly particular about where it will take root.  It will grow just about anywhere if the ground is soggy.  In Scotland, if you travel along Rt. 97 from the center of town toward Baltic you will notice an attractive little marsh and pond on the left just a little past The Highland Campground.  Phragmites australis australis has established a sizable colony there.  It looks quite lovely with its frothy plumes blowing in the summer breeze however left to its own devices for too long it may eventually guzzle down the entire the pond!  Seriously, it really does have the capacity of lowering a water table, and it can also alter water flow in areas along brooks or streams, but the main problem, as with all the other invasive plants we have been discussing, is that Common Reed is displacing native plants as well as the animals that require native plants for their survival. This plant's aggressive growth habits easily keep native species, both plants and animals, from growing and thriving in its midst. 

How To Remove

I guess another of the reasons this plant has inherently conquered the world is, once it gains a foothold, its removal is a task involving some significant labor.  A way to remove Phragmites australis australis without using herbicides is a marvelously murderous sounding method that could be the title of a pulp murder mystery called "Cut to Drown".  This method involves hand cutting the plant to a level six inches below the water level. As a less physically taxing alternative to hand cutting, one might try a gas-powered aquatic vegetation cutter.  A simple internet search will bring up several to peruse.  These cutters are specifically designed for the task of cutting vegetation under the water level in lakes and ponds. Cutting below the water level starves the plant of the oxygen it requires to survive.  Cutting should be done from mid spring to mid fall.  The plant should not be cut when it is in its dormant stage from mid fall to early spring.  When cutting, every piece of greenery needs to be cut below the water surface because, believe it or not, the plant can "snorkel" and will survive if any piece of leaf or stem remains above water.  The cut canes should be placed in a tarp, as you are cutting them, for removal.  All cut canes need to be removed from the area.  Proper disposal method is bag and burn. The area will need to be monitored, and this process may need to be repeated periodically as new growth forms.

A slightly different option requires a controlled burn.  With all required permits and a trained team in place, a prescribed burn can be done ahead of the cut to drown procedure.  This will eliminate the bulk of the reeds requiring removal and disposal. The burn should be done when the plant is in its dormant and dry stage during late fall to early spring.  When considering a controlled burn, great care needs to be taken to avoid loss of wildlife and native plants.  A burn will only remove the portion of the plant that is above water.  It will not kill the rhizomes, stolons, or any portion of the plant below the water line.  It will make the task of cut to drown procedure a little easier once the plant is back in its growing cycle as there will be significantly less biomass to remove.

Yet another method- Please don't shoot the messenger! I know nobody wants to hear this, but the most common method used to eliminate this plant, and many other invasive helophytes, involves the use of herbicides.  While none of us like the thought of using herbicides in our ponds lakes or waterways, keep in mind any aquatic environment filled with invasive weeds is not good for native wildlife or plant life either, so here goes- There is a Glyphosate solution specifically created for aquatic use, and there are other herbicide solutions specifically designed for pond and lake use that contain various other active ingredients besides Glyphosate as well, with each targeting a different plant.   Of course, all herbicides need to be applied using great precision and care so as not to damage any native plants or aquatic wildlife.  A chart which detailing herbicide application for this plant can be viewed at the Michigan's Citizens Guide by copying and pasting or clicking on the following link.  

https://www.greatlakesphragmites.net/files/HerbicideQuickGuide.pdf .  

The entire website, which you should be able to access from the above link, has lots of information on the control of this plant.  I promise this site is not all about using herbicides!  Michigan has approximately 11,000 lakes of all sizes so they might be considered experts on the topic of eradicating invasive plants from waterways!

The link below to the Connecticut Agricultural Experiment Station provides clear photos showing the various differences between native and non-native Phragmites.  You may need to copy and paste the below link to get it to open.

https://portal.ct.gov/-/media/caes/documents/publications/fact_sheets/plant_pathology_and_ecology/phragmitesfactsheetpdf.pdf

 

Burning Bush AKA Winged Euonymus, Euonymus alatus

This plant is native to central and northern China, Japan and Korea where it is used in traditional Chinese and Korean medicine.  Burning bush was introduced to the United States as an ornamental in the 1860's. It was considered desirable for its colorful berries and bright red or pinkish red foliage displayed during the autumn season. Winged euonymus gets the "winged" portion of one of its common names from the unusual appearance of its branches which have distinctive thin corky ridges along opposing edges that resemble wings.  Because of this shrub's hardiness and its attractive fall foliage, it was frequently selected as a decorative hedge planting along interstate highways. The plant is not especially fussy about where it lives.  It will grow in sun or shade, and it is adaptable to most soil types.  Wherever it grows it produces abundant seeds that birds and small mammals relish.  Though that seems a good thing, unfortunately as the seeds pass through the digestive tract of these birds and mammals they remain fertile and are deposited far from the original feeding site.  In this new site seeds germinate and form new colonies.  Like several other shrubs considered invasive, burning bush can also take root from any branches that contact the ground.  This is called vegetative propagation.  Over the years this plant, like many other invasives, has escaped cultivation and has naturalized in our woodlands where it chokes out native plants.  Given its aggressive growth habits this shrub will continue to spread. Some studies suggest that it will even out compete other invasive plants!  In much of New England, including Connecticut, it is not legal to purchase, propagate, or transport this shrub or any of its cultivars. Having an awareness of the impact this shrub can have on our woodlands and open fields; you might want to seriously consider its removal should it be an ornamental shrub presently growing on your property.  There are many alternative plantings that make attractive replacements.  Inserting a native planting in place of this shrub will also help to discourage regrowth of Burning Bush from any remaining seeds that germinate after the plant's removal.  There are many to consider such as maple leaf viburnum, American holly, or winterberry.

HOW TO REMOVE

The shrub's "winged" branches make it easily identifiable no matter the season.  If you happen to spot young specimens of this plant growing in the forest, you may want to take a few minutes to remove them.  Small plants around 2 feet high or less can be quite easily pulled.  You can leave them hanging in nearby shrubs where they will dry out.  Larger specimens will require a shovel or fork to disengage the root from the soil.  It is easier to gain access to the lower part of the shrub if you first lop off most of the branches.  If you are unable to remove this shrub from the soil, another recommended option is to cut off all branches and the main trunk during its growing season and follow up with an application to the cut areas with a concentrated herbicide such as Glyphosate or Triclopyr.  To eradicate a very large infestation of this shrub, the recommendation is foliar spray of Glyphosate or Triclopyr applied during the summer growing season.  Keep in mind Glyphosate is a non-specific herbicide killing both broad leaf plants and grasses.  Triclopyr kills only broad leaf plants and will not harm grasses.