Invasive species are found throughout the world
Invasive species are a problem world-wide and there isn't a country or region that hasn't seen harm done by these interlopers. These are non-native plants or animals that cause ecological or economical harm to the land or commerce. They can alter habitats and out-compete natives to the point of extinction. Whether they were introduced accidentally or intentionally, invasives can often take over to the point of crowding out plants and animals that belong. The best experts can tell, there are about 50,000 non-native plant and animal species where they do not belong in this world. That includes reptiles, insects and fish as well. Many of them actually play nice and do no harm, however others are major problems for agriculture and wildlife.
Humans are responsible for most invasive species
As mankind developed the means to travel long distances, there has always been those who wanted to see what was out there. Whether it was explorers charting unknown lands or settlers searching for a better life, they were all responsible for scattering many plants and animals around the world. They all wanted something familiar from home, whether it was seeds or livestock. Some were welcome and adapted just fine. The European honeybee is a prime example. Settlers from Europe brought their beehives with them to new lands and the honeybees have never been problematic. However, the Africanized honeybee is another story. These bees are hybrids created by interbreeding the peaceful European honeybee with the more aggressive east African honeybee, a subspecies that was native to the African continent. It was thought that the hybrid bees would produce more honey in tropical areas, however in 1957, these bees escaped quarantine in Brazil and started interbreeding with the European honeybee already there. These hybrid bees are also known as killer bees, as they are very defensive of their hives and hundreds of them will chase and sting anything that disturbs them for long distances. They have steadily moved north and arrived in Texas in the 1990's and have been responsible for over 1000 deaths.
Many invasive species were intentionally introduced
Examples of intentional introductions with terrible results would be kudzu and Japanese honeysuckle. Kudzu was introduced in the late 19th Century as an ornamental that grew so fast that it quickly covered anything in its path. The thought was to provide quick shade. In the early 20th Century the government even encouraged farmers to plant it to prevent soil erosion and as animal fodder. Thousands of acres were planted across the South during the Depression by the Civilian Conservation Corps. The vine isn't a problem in Asia because there is an insect that keeps it in check. The kudzu bug has finally made its way to North America where it is happily reducing the stranglehold that kudzu has on our southern lands. Unfortunately, this insect is also an invasive species and has added our agricultural crops to its list of preferred foods. Just like the kudzu, Japanese honeysuckle was introduced to North America as an ornamental in the early 20th Century. It was quickly prized for its rapid growth with attractive, fragrant flowers. The twining and twisting vines rapidly cover and choke out less aggressive native plants. Birds scatter the seeds and the plant has the ability to produce roots from every leaf node. It is still commercially sold in nurseries even though it has achieved noxious and invasive status in a number of states. There are a number of articles on the internet with care instructions and very little information on how to control it. The sweet smelling blossoms are attractive to humans, hummingbirds and honeybees alike, so it is tempting to plant some, however it is best to avoid it. There are native options such as the coral honeysuckle that are better choices.
Stinkbugs are agricultural problems and winter pests
Even in this day and age, invasive species are still being introduced. The brown marmorated stinkbug probably hitched a ride on container ships and was first noticed in 1998 in Pennsylvania. It has since spread to 34 states and is a agricultural pest that finds many crops tasty. They do damage to orchards, vineyards, vegetable gardens, soybean and corn crops. Brown marmorated stinkbugs have a high tolerance for cold weather, however they do like to congregate in groups and find their way indoors during the winter. They are not so noticeable in sheds and barns, however they also like the comfy conditions in people's homes. That's where we discover why they are called stinkbugs. If they are disturbed, they emit a foul odor similar to fermented, dirty gym socks. Unfortunately, they are becoming resistant to insecticides, so are harder to control than in the past.
Many common plants and animals are problems out of their home areas
Other invasive species inadvertently introduced are the zebra mussel, released with ship's ballast in the Great Lakes and now plagues most of the eastern waterways. They attack native mussels and reproduce at an alarming rate. Purple loosestrife (seen in the lead image to this article) was also released in ship's ballast and the purple-blooming aquatic plant clogs waterways and chokes out native species. We've all heard about the murder hornets that have been spotted in the Northwest. These insects probably sailed across the Pacific in shipping containers. They take a special delight in attacking honeybee hives and decapitating them. The Asian honeybees have developed a system of sentries that attack and kill the murder hornet scouts before they can make their way back to their home nest. Our honeybees haven't developed this warning system, so they are at risk. Rabbits introduced into Australia have reproduced, well...like rabbits. They are serious agriculture and environmental pests and concentrated efforts to eradicate them have been going on for nearly 200 years with poor results. We've all been horrified when swarms of Japanese beetles invade our gardens. I've picked hundreds off my roses and daylilies into buckets of soapy water. Also here in West Kentucky, our beautiful lakes are swarming with Asian carp. Several species of carp were imported by farmers in the South and escaped captivity from their ponds during floods into the Mississippi River and soon spread to surrounding rivers and lakes. They have no natural predators and have multiplied to the point that our native game fish are endangered. They also harm our recreational visitors' experience by jumping out of the water in huge schools when disturbed. The War on Carp has been declared and millions of dollars are being spent to remove them from waterways from Texas to Canada.
Be vigilant, do your part and don't spread invasive species
Gardeners can do their part in reducing the impact of invasive species. First of all, plant native. Whenever you are planning a new garden, do a little research and learn what native plants have the characteristics you want. Choosing them over non-natives helps prevent invasive spread and also does double duty as butterfly and pollinator habitat. If you already have non-native plants in your garden, remove them. Chances are, there are native plants that have a similar look or habit. Always thoroughly clean your hiking equipment and boots before leaving an area. This will ensure that any seeds or pieces of plants that can take root are left behind. When fishing, wash your boat and equipment before leaving an area and don't dump unused live bait in the water. If your dog goes with you, make sure it doesn't have any seeds in its fur or between its toes before you leave an area. Participate in clean-up days at your local park or nature preserve where they remove invasive plants from their grounds. This week is just to raise awareness and we need to put the words into action all year round. If we all pay attention, educate ourselves and do our part, we can lessen the impact that invasives have on our neighborhoods and environments.