What is an Invasive?

• Usually Non-native. There can be aggressive native plants.
• No or few predators keep it in check
• Spreads aggressively. Sometimes it chemically suppresses other competing plants.
• Contributes to monoculture as it takes over.
• Reduces diversity.

Why do we care about invasive plants?

• Monoculture is boring.
• Native plants are crucial for biodiversity. (Read about Natives and Keystone plants)
• Native plants are adapted to our conditions (manage in stormwater and drought)

How to remove invasives?‍

1. Pullout as much as possible. Weaken if you cannot remove.
2. Smother.  With cardboard or plastic (solarize).
3. Girdle with knife.
4. Last choice: Limited poison. Cut and paint with Garlon or similar. Or girdle with garlon. Do not spray. Poison kills soil microorganism, good fungi. Vinegar with salt requires constant reapplication and may damage soil.

Nature abhors a vacuum

-Aristotle

Remember to plant or seed after removing invasives. Plant densely to keep out weeds.

‍

Native Alternatives to Invasives

• Invasive: Lesser Celandine. Native Alternatives: Celandine poppy, wild strawberry, common blue violets, Virginia bluebells.
• Invasive: Common or Glossy Buckthorn (especially pull females with berries.) Native Alternatives:  chokecherry, Chokeberry, Hazelnut, Missouri Gooseberry, Wild plum, Blackhaw viburnum or nannyberry.‍

• Invasive: Dames Rocket. Natives: Woodland or Prairie Phlox. (Dames Rocket has 4 petals and the natives have 5 petals.)

• Invasive: Garlic Mustard. Native Alternatives: Poppy mallow, Ohio spiderwort, White turtlehead, Foxglove beardtongue, many summer bloomers.
• Invasives: Mugwort or Motherwort.  Natives: Beebalm, blue vervain, great blue lobelia or cardinal flower.
• Invasive: Multiflora Rose. Natives: native roses, like Illinois or climbing rose (Rosa setigera), Carolina rose (Rosa Carolina), or early rose (Rosa blanda).

• Invasive: Winged burning bush. Native Alternatives: Wahoo, Cherry, chokecherry, Chokeberry, Hazelnut, Blackhaw viburnum or nannyberry

• Invasive: Tree of Heaven or Norway Maple.  Native Alternatives: many native trees, such as oak, hackberry, tuliptree and more.
• Is Lawn an Invasive? Native Alternatives: Pennsylvania, Ivory or James Sedge, or Buffalo grass.

‍