what-are-invasive-plants

What Are Invasive Plants?

Jane Marsh - March 17, 2021

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You see plants everywhere. You might plant vegetables in your garden. Maybe there are some weeds around your yard that you pull out or try to mitigate. Plus, in nature, there is a wide and diverse variety of vegetation. 

While most of these plants are likely native to the area or intentionally planted, others are not. Some of the plants you see might be invasive. Invasive plants can spread like wildfire if not taken care of or removed from an ecosystem. 

Whether you’re aware or not, you probably have invasive plants right in your backyard! 

Definition of Invasive Plants 

What are invasive plants anyways? To put it simply, invasive plants are those species that are alien to the environment, grow out of control and eventually disrupt the ecosystem. Invasive plants take over without a care for their surroundings. These can be trees, shrubs, vines, flowers, grasses, roots or any other plant you can think of. 

Invasive plants cause environmental harm and can also cause economic or even social damage. They’re undesirable because they’re challenging to control. Often, they don’t have any predators, prey or other things that can stop them from spreading or harming the environment. In efforts to manage them, a lot of money can be spent, which is where the economic harm comes into play. 

Some invasive species have even been known to harm human health, as a person could have an allergic reaction to them. Most invasive plants come from other countries, but they can travel from state to state. While these plants are introduced to a new region, they’re not always considered invasive.  

Difference Between Invasive and Other Plants

As previously mentioned, not all non-native plants are invasive. Here are some of the defining characteristics of an invasive plant species:

  • They’re not native to their country of origin. 
  • They spread and reproduce by roots, shoots or seeds.
  • They grow and mature at a fast rate. 
  • They can grow in various conditions, whether it be rainy, dry or even a mixture.
  • They tend to colonize an entire ecosystem.

Invasive plants thrive because there are often no animals or other plants that eat them or compete. These are the typical characteristics of invasive plants. 

Just because a plant is non-native doesn’t mean that it is invasive. Many non-native plants grow and thrive in countries all around the world. A non-native plant is introduced, whether by accident or intentionally, to a country or other environment not of its origin. 

Most of the time, non-native plants cannot grow or spread without humans’ help, and they’re not threatening to the ecosystem, economy or humans. Plants that are non-native and don’t need human assistance to spread are considered naturalized. 

Where Do Invasive Plants Come From?

Invasive plants may come from various sources. However, the most common is through human activity. Often, humans bring in plants for ornamental, agricultural or floricultural purposes. 

While these activities are intentional, what’s not intentional is when people dump these into a compost pile or throw seemingly dead plants into a field or the woods. That’s when the invasive species spread.

Additionally, invasive plants may spread through travel and trade. For example, you might go to a foreign country for a vacation or a volunteer trip. One day, you wear your sneakers for a walk. You might brush up against a plant, where little seeds get onto your shoe. You pack your bags, travel home, and the next day, you go for a run in those same sneakers. The seeds might knock off and find soil — and boom, the invasive species begin to grow.

Other sources are more natural ways of spreading. Climate change causes typical patterns of rain or temperatures to allow invasive plants to move locations more easily. 

Impact of Invasive Plants on the Environment

If it wasn’t already obvious, invasive plants have a significant impact on the environment. They degrade the native environment and can deplete their surroundings. This can lead to endangerment or even extinction of native species. 

Biodiversity also decreases. Once invasive plants take over, they may kill native or non-native, unharmful plants. They become somewhat of a mono-crop, which causes the soil to lose integrity and drives down biodiversity.

When invasive plants enter a new ecosystem, the habitat is permanently altered unless the species can be eradicated, which often isn’t the case.

Common Invasive Plants in America

A plant doesn’t have to be from a different country for it to be invasive — it can be from the state right next to yours or even the other side of your own state. Below are some common invasive plants in America that you have likely seen. 

  • Wisteria: This invasive plant is native to China. While it looks beautiful with its purple flowers, it grows vigorously.
  • Japanese Honeysuckle: Japanese honeysuckle often grows large and quickly, preventing other vegetation from receiving light and nutrients. 
  • Common Buckthorn: People coming to America wanted to bring a piece of home with them, so they brought common buckthorn. However, it quickly takes over other shrubs and attracts pests.
  • Giant Hogweed: This plant is both on the invasive species list and on the noxious weed list. Although it was supposed to be an ornamental plant, the sap can cause burns and blindness if you touch it.

These are just a few examples of the many invasive plants in America. Be careful of what you plant to stop the spread of them.

You Can Stop the Spread of Invasive Plants

One of the best ways to slow the spread of invasive plants is to be aware of them. Don’t plant any in your yard or other places, and be careful of your disposal of indoor ornamental plants. If you see invasive plants on your property, remove them immediately and make sure they’re dead so they don’t spread. 

Rather than planting invasives, go for native plants. This will boost biodiversity and will keep your yard free of invasives. 

About the author

Jane Marsh

Jane Marsh is the Editor-in-Chief of Environment.co. She covers topics related to climate policy, sustainability, renewable energy and more.