ALIEN INVASIVE SPECIES

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One of the primary purposes of our nature preserves is the protection of native Indiana species of plants and animals.  Many alien species can live alongside our natives.  But some aliens will out-compete or harm our natives.  These are "invasives" and we cannot have them in the preserves.  Depending on the harm caused by a given alien species, all of some invasives must be removed and other invasives from only parts of certain preserves.  Below are alien invasives that we are currently combating"

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PLANTS

 

Autumn Olive - 

From Ohio Division of Natural Areas and Preserves:  Autumn-olive is native to China and Japan. It was introduced to the United States in 1830 and is distributed throughout the state. Russian-olive is originally from Europe and Asia. It was introduced to North America in the early 1900s and is found throughout Ohio. Historically these plants have been used for erosion control, strip mine reclamation, wildlife habitat, and in landscaping.  Autumn-olive and Russian-olive aggressively out-compete native plants and shrubs. They grow rapidly and re-sprout heavily after cutting or burning. Both species are prolific fruit producers, with seed dispersal mostly accomplished by birds.  Hand-pulling seedlings and sprouts is effective in the early spring when the ground is moist and the entire plant and root system can be removed. Other forms of control, such as mowing and burning, without the application of a herbicide usually contribute to a larger number of root sprouts.

Buckthorn -

From Ohio Division of Natural Areas and Preserves:  Glossy buckthorn and common buckthorn were introduced to North America from Eurasia as ornamental shrubs for fence rows and wildlife habitat and are still used in landscaping. These species are distributed throughout the northeast and north central U.S. Both species are frequent in the central and northern part of the state.  Both glossy and common buckthorn have a wide habitat tolerance, rapid growth rates and extensive root systems. Both species produce abundant flowers and fruits throughout the growing season. Seeds are widely dispersed by birds. Once established, these species aggressively invade natural areas and form dense thickets displacing native species. They leaf out very early in the growing season and keep their leaves late into the fall helping to shade out native trees, shrubs and wildflowers.  Prescribed burning has been used to control buckthorns in some natural areas. Fire will top kill stems, however re-sprouting will occur and seed germination may increase. Several years of burning may be necessary to control these species and may not be appropriate in some natural areas. Hand pulling may be successful in small infestations, although several seasons may be required as re-sprouting will occur if part of the root is left behind. This method also disturbs the soil, increasing seed germination. Repeated mowing has been reported effective in maintaining open areas and preventing seedling establishment.

Canada Thistle - 

From Ohio Division of Natural Habitats and Preserves:  Canada thistle occurs in nearly every open habitat within its range and tolerates nearly any soil type that is not waterlogged. In natural areas, it is a particular problem in old fields, prairies, savannas, and early successional forests. It can also be a problem in wet sedge meadows where it invades areas above the waterline.  Despite its name, Canada thistle is not native to Canada or even to North America. It is native to eastern and northern Europe and western Asia, and was introduced to North America in the 1600s. It has spread throughout all of the United States except the southeast. It is found throughout Ohio.  The extensive root system of Canada thistle allows it to out-compete and displace many native species, especially in degraded prairies where native species are not well established. Spreading both by seed and rhizome, Canada thistle can create monocultures covering large areas. The wind-dispersed seeds may remain viable for 20 years or more, allowing it to spread quickly and making it difficult to eradicate. Prescribed burning, especially in the spring, can be effective by reducing thistle density and allowing native species to compete for resources. Mowing will temporarily reduce the amount of Canada thistle, but will not kill it unless mowing is repeated often for many years - which can also harm native plants as well. Hand pulling is usually ineffective since small portions of broken taproot can easily regenerate.

The state of Indiana considers it a detrimental weed: must be destroyed.

 

Crown Vetch - 

 

From Southeast Exotic Pest Plant Council Invasive Plant Manual:  Crown vetch spreads vegetatively by underground roots or rhizomes and by seeds. These perennial roots primarily serve to anchor the plant and as a storage structure. Flowers emerge May through August and seeds will mature by September. Seeds remain viable in the soil for several years requiring consistent post treatment monitoring.  Crown vetch is native to Europe, Asia and Africa. It is widely cultivated as a ground cover and for erosion control in the U. S. since the 1950’s. It has become naturalized in much of the U.S. and southern Canada. In some areas, crown vetch will totally dominate pastures and abandoned fields.  Crown vetch is primarily found along roadsides, fields, and road cuts. It does well rocky dry sites as well as moist well-drained areas. It is intolerant of shade but will tolerate sparse shade along the edge of forested areas.  Hand pulling of mature plants can be effective when controlling small initial infestations. Mowing plants in the flower bud stage for two or three consecutive years may reduce the vigor and control further spread. Plants should be cut before seeds mature and as low to the ground as possible. Impact to adjacent native plants should be minimized as much as possible.

 

Dame's Rocket -

 

 

 

Garlic Mustard -

From Ohio Division of Natural Areas and Preserves:  Garlic mustard originated in Europe and was introduced to the United States for herbal and medicinal purposes. It was first recorded in the United States in 1868 in Long Island, New York. By 1991, garlic mustard had invaded 28 Midwestern and northeastern states. Garlic mustard can be found throughout the state of Ohio.  Garlic mustard aggressively out-competes native species in the understory of forests and woodlands. This plant begins growth in early spring and ends growth later in the season than most native species. As a result, garlic mustard shades out native wildflowers and out-competes native seedlings. Garlic mustard grows in dense clusters and can displace most herbaceous native plants within 10 years. Large quantities of seed are produced and can remain viable in the soil for up to 7 years. The seeds are dispersed by wind, water and transported by animals and humans.  Mechanical controls of garlic mustard include hand-pulling and cutting, and are most effective on smaller infestations. Hand-pulling of plants can be very effective, although labor intensive. Care must be taken to insure that the entire plant is removed and that all plant materials are bagged and moved off-site. A plant can continue to mature and produce seeds even if it has been pulled up. Hand-pulling and removal must continue until the seed bank is exhausted (at least 7 years).  Cuttng populations of garlic mustard is effective for medium to large concentrations of plants. Stems may be cut by mowing, brush-cutting, or by hand when the plants are in flower. This can result in total mortality of the plants, however it does not affect the seed bank. Cutting must continue every year until the seed bank is exhausted. Prescribed fire can be an effective control agent in controlling garlic mustard given the proper location and fire intensity. Repeated, effective burns over several years are necessary.

Honeysuckle -

 

From Indiana DNR:  Bush honeysuckles have been widely used for many years as ornamental bushes, for wildlife habitat and for erosion control. These plants out-compete and displace native plants, altering natural habitats by decreasing light availability and depleting soil moisture and nutrients. While readily eaten by migrating birds, bush honeysuckle berries are carbohydrate-rich and do not provide the high fat content needed for long flights. 

From Ohio Division of Natural Areas and Preserves:  Amur, Morrow and Tatarian honeysuckles are native to China, Korea and Japan. Introduced into the United States in 1846 as ornamental plants, they have escaped cultivation due to high seed production and to the fact their seeds are readily eaten and dispersed by birds. These honeysuckles are distributed throughout Ohio with Amur being more problematic in southwestern Ohio, Morrow in northern Ohio, and Tatarian throughout the state.  These vigorous shrubs shade out native vegetation, particularly in the woodland understory. They are able to out-compete native wildflowers for light and other resources. Bush honeysuckles green up earlier in the spring than most other plants, giving them an advantage over other species. Each produces abundant amounts of seed which are spread by birds and other animals.  The bush honeysuckles in less dense populations can be pulled, making sure that all the roots have been removed. Any remaining roots in the ground are likely to re-sprout. A pulaski, Weed Wrench, or other similar tool may be used to remove the plant from the ground.

Kudzu -

 

From Indiana DNR:  Kudzu, brought to the U.S. from Asia in 1876, was widely planted as an ornamental plant, as forage for livestock and as erosion control. The plant adapted well to the climate of the southeastern U.S., and can be seen covering trees, utility poles and even buildings. The U.S. Department of Agriculture declared it a weed in 1972.

 

Multiflora Rose -

 

From Plant Invaders of Mid-Atlantic Natural Areas:  Multiflora rose was introduced to the eastern United States in 1866 as rootstock for ornamental roses. Beginning in the 1930s, the U.S. Soil Conservation Service promoted it for use in erosion control and as "living fences" to confine livestock. State conservation departments recommended multiflora rose as cover for wildlife. More recently, multiflora rose has been planted in highway median strips to serve as crash barriers and to reduce automobile headlight glare. Its tenacious growth habit was eventually recognized as a problem on pastures and unplowed lands, where it disrupted cattle grazing, and, more recently, as a pest of natural ecosystems. It is designated a noxious weed in several states, including Iowa, Ohio, New Jersey, Pennsylvania and West Virginia.

From Ohio Division of Natural Areas and Preserves:  Multiflora rose was introduced from Japan, Korea and eastern China in the 1860s as rootstock for ornamental roses. In the 1930s, it was widely promoted as a "living fence" for soil conservation and in wildlife programs. It is found throughout the United States with the exception of the Rocky Mountains, southeastern coastal plains and western desert areas. In Ohio, multiflora rose has a widespread distribution in pastures, woodlots and noncrop lands.  Thickets of multiflora rose can successfully displace native plant species. Multiflora rose reproduces from seed and by rooting from the arching stems. It has been estimated that an average plant produces a million seeds per year, which may remain viable in the soil for up to twenty years.  Light multiflora rose infestations can be eradicated using a shovel, provided the entire root system is removed. For control of more severe invasions, mowing or cutting several times per growing season for 2-4 years can be effective. In some situations, a prescribed burn during the early growing season may be an appropriate method for controlling severe infestations.

The state of Indiana prohibits the planting of multiflora rose without a permit.

 

Periwinkle (Myrtle) -

Plant Invaders of Mid-Atlantic Natural Areas:  Common periwinkle is a vine or subshrub in the dogbane family (Apocynaceae) that is native to Europe and was introduced for ornamental purposes many decades ago. It occurs throughout the United States in at least 36 states, has escaped cultivation and is invading natural areas. Common periwinkle poses a threat to native plants and communities because it grows vigorously, forming a dense monotypic evergreen groundcover that displaces and excludes most other plants, including native wildflowers. It spreads by vegetative means only.  Periwinkle can be removed by digging, raising the runners with a rake, and mowing the plants. All of the plant must be removed.

Purple Loosestrife -

 

From Ohio Division of Natural Areas and Preserves:  Purple loosestrife was introduced to North America from Europe and Asia in the early 1800s as a contaminant in ship ballast, as well as a medicinal herb and garden plant. It escaped and became a pioneer species of newly constructed waterways and canals. Purple loosestrife occurs throughout the United States with its heaviest concentrations in the northeast. Although Lythrum salicaria is currently no longer available to purchase, cultivars continue to be distributed. In Ohio, this plant can be found throughout the state, although it is more established in the northern half.  Purple loosestrife adapts readily to natural and disturbed wetlands. As it establishes and expands, it out-competes and replaces native grasses, sedges, and other flowering plants that provide a higher quality source of nutrition for wildlife. Purple loosestrife forms dense, homogeneous stands that restrict native wetland plant species and reduces habitat for waterfowl. Seed production is as prolific as the vegetative growth. Seeds are widely distributed by animals, machinery and people and in waterways.  Small infestations of purple loosestrife can be removed by hand. The entire root system must be removed from the ground. All plant material should be bagged and removed from the area to eliminate re-sprouting. Larger populations are harder to control using mechanical means. Mowing should not be used because it can increase the spread of the population by dispersing seeds and exposing the seed bank.

 

The state of Indiana prohibits the planting of purple loosestrife without a permit.

 

Tree of Heaven -

 

From Indiana DNR:  Ailanthus altissima, also called Tree of Heaven or Stinkwood, is a native of China and was introduced to the U.S. in 1784. The tree was planted as an ornamental tree in urban areas because of its ability to thrive in disturbed and polluted areas where nothing else will grow. One tree can produce up to 350,000 seeds per year, which accounts for its invasion into natural forests, where it can be found in nearly any habitat except wetlands.

From Ohio Division of Natural Areas and Preserves:  Tree-of-heaven can be found in nearly any habitat except wetlands. It thrives in disturbed soils in both urban and natural areas. In natural areas, tree-of-heaven invades fencerows, roadsides, woodland edges, successional forests, and open forest thickets. Tree-of-heaven thrives in poor soils and tolerates pollution well, a reason why it is often planted in urban areas.  Tree-of-heaven was introduced to the United States from China. It was first brought to Philadelphia as a garden plant in 1784. By the mid 1800s, it was well established as a nursery tree because of its ability to grow nearly anywhere. Chinese immigrants that came to the United States to work in the gold mines also introduced it to California as a medicinal plant. Absent only from the northern plains of the United States, tree-of-heaven is found throughout Ohio. It poses the greatest threat to successional forest areas of Ohio.  One mature tree-of-heaven can produce up to 350,000 seeds per year. These seeds are easily airborne and can be transported by water and birds as well. Germination of seeds is quite high. Mature trees also reproduce extensively by sending up root suckers and sprouts from cut stumps. Sapling growth can reach 3-4 feet a year and can outgrow nearly any native tree, outcompeting natives for light. The roots give off a toxin that acts as a herbicide that can kill or inhibit the growth of other plants. Tree-of-heaven is somewhat shade-tolerant and can grow quickly when released by gaps in the forest canopy caused by windfalls, logging or defoliation due to insect pests such as gypsy moth.  Young seedlings may be successfully hand-pulled if the entire root system is removed. If small portions of the root system are left, regeneration is likely. Cutting alone is usually not effective since this merely stimulates aggressive root suckering and stump sprouting. However, cutting large trees can help control its spread by removing seed-producing trees.  It is of utmost importance to kill the entire root system.

ANIMALS

 

Emerald Ash Borer - From www.emeralashborer.info:  Emerald ash borer (EAB), Agrilus planipennis Fairmaire, is an exotic beetle that was discovered in southeastern Michigan near Detroit in the summer of 2002. The adult beetles nibble on ash foliage but cause little damage. The larvae (the immature stage) feed on the inner bark of ash trees, disrupting the tree's ability to transport water and nutrients. Emerald ash borer probably arrived in the United States on solid wood packing material carried in cargo ships or airplanes originating in its native Asia. Emerald ash borer is also established in Windsor, Ontario, was found in Ohio in 2003 and northern Indiana in 2004.  Learn more at http://www.entm.purdue.edu/EAB/

 

 
House Sparrow - aggressive cavity-nesting bird that is displacing the native bluebirds.  They not only nest in the same type of place, but they will destroy bluebird eggs and nests as well.