Thinking about enhancing your garden's aesthetic while promoting local biodiversity? The solution lies in swapping out invasive plants for native alternatives. Discover how you can make a sustainable impact on your landscape this spring!
Invasives such as Callery pear and Burning bush were introduced to North America for their ornamental appeal but have since wreaked havoc on local ecosystems. These invasive species have outcompeted native flora, diminishing biodiversity and disrupting local wildlife habitats. It’s crucial for every gardener to understand the implications of these plants and consider native replacements that offer beauty and ecological benefits. Here’s a guide on Five of Pennsylvania’s Worst Invasive Trees and Shrubs and their native replacements.
^^1. Callery Pear (Pyrus calleryana)
The Callery pear, often referred to as Bradford pear, boasts early spring blooms and vibrant fall colors, making it a popular choice for landscaping. However, this tree produces a foul odor when in bloom and has weak wood prone to breaking in storms. Additionally, it provides little to no support for local wildlife as a host plant for caterpillars, a crucial food source for many bird species.
Replace with: Serviceberry (Amelanchier spp). This native shrub offers clusters of white flowers in spring, followed by dark purple, edible berries in summer. Moreover, the Serviceberry has striking fall foliage, showcasing oranges and reds, and supports various pollinators, including butterflies and bees. Reaching heights of up to 25 feet, it thrives in sunny environments, making it ideal for gardens needing vertical interest.
^^2. Burning Bush (Euonymus alatus)
With its bright pink-red leaves in fall, Burning bush has been a sought-after ornamental shrub for many homes. However, it’s known to create dense undergrowth, crowding out native plant species while being susceptible to numerous pests and diseases. Birds may eat its berries, but the plant ultimately disrupts local ecosystems.
Replace with: Highbush Blueberry (Vaccinium corymbosum). This native plant not only provides attractive spring blossoms but also yields delicious, nutritious berries enjoyed by both humans and wildlife. The Highbush Blueberry features captivating fall foliage in shades of red, orange, and purple and grows well in moist, acidic soils. Additionally, it stands between 6 to 12 feet tall, adding height and attractiveness to any landscape.
^^3. Japanese Barberry (Berberis thunbergii)
Japanese barberry adds a pop of color with its yellow spring flowers and striking fall foliage. However, it poses significant risks as it can create a monoculture in forest understories, increase soil pH, and directly contribute to tick populations by providing humidity and cover.
Replace with: Virginia Sweetspire (Itea virginica). This native shrub features showy white flower spikes that attract butterflies and bees, while its fall color transitions into beautiful shades of red and yellow. Preferring moist conditions and thriving in filtered sunlight, Virginia Sweetspire can grow up to 10 feet tall, and dwarf varieties offer options for smaller spaces.
^^4. Butterfly Bush (Buddleia davidii)
While the Butterfly bush serves as a nectar source for adult butterflies, it does not support caterpillars, which are essential for nurturing butterfly populations. Furthermore, it produces thousands of seeds that disperse widely, often inongly ecosystems.
Replace with: Summersweet (Clethra alnifolia). This alternative blooms in mid-summer with fragrant, showy flowers that attract not only butterflies but also bees and hummingbirds. Known for its adaptability to moist soils, Summersweet features stunning yellow and gold leaves in fall, achieving heights of around 6 feet, making it suitable for rain gardens and varied landscapes.
^^5. Norway Maple (Acer platanoides)
The Norway maple was initially hailed for its large leaves and shade, making it a favored city tree. Despite its appeal, it tends to grow in colonies, significantly shading out other plant life and monopolizing moisture due to its shallow roots.
Replace with: Sugar Maple (Acer saccharum). Popular for its spectacular, multicolored fall foliage, the Sugar maple can reach impressive heights of 60-80 feet and supports a plethora of forest wildlife, including the imperial moth and other caterpillars. This native treasure thrives best in well-drained soils while requiring full to partial sunlight.
^^A New Initiative for Biodiversity
Pennsylvania is actively working to reduce the impact of invasive species with the 2025 Pennsylvania Invasive Replace-ive Program, which incentivizes landowners to remove invasive plants and replace them with native species. Registered participants can receive up to five free native trees as replacements if they provide proof of removal of specific highly invasive species.
This endeavor aims to enhance local biodiversity and promote healthier ecosystems. While the registration for this year may be full, there are waitlists available at the distribution points that allow interested individuals to reserve their trees for the following distribution opportunities.
Taking steps toward creating a more sustainable garden not only benefits the environment but also enhances your landscape's beauty. By making wise choices today—for yourself, the local wildlife, and future generations—you pave the way for a thriving ecosystem. Consider these native replacements and join the movement to restore Pennsylvania’s rich plant diversity!