Invasive Honeysuckle

Lonicera spp.

Characteristics

Invasive honeysuckle, a woody shrub/small tree in the Caprifoliaceae family, is an understory invasive that produces large amounts of seeds and outcompetes many native species. It’s also sun- and shade-tolerant and can live in many different soil, moisture, and habitat conditions. There are three invasive honeysuckles in our area: Morrow’s honeysuckle (Lonicera morrowii), Tatarian honeysuckle (Lonicera tatarica), and Bell’s honeysuckle (Lonicera x bella). Honeysuckles are often planted as ornamentals but have a tendency to escape into natural habitats. Common identification characteristics are:

• Grows to heights of 12 feet
• Leaves are opposite, elliptic to oval or oblong in shape, 3-6 centimeters long, gray-green in color
• Multiple branching stems, gray-tan bark, pith is brown and hollow
• Flowers are small and tubular, paired and borne on stalks arising from the leaf axils, can be white (Morrow’s), white-pink-red (Tatarian), or just pink (Bell’s), blooms May-June
• Fruits are red-orange and paired

Note: These plants can be confused with the native American fly honeysuckle (Lonicera canadensis). To differentiate between native and invasive, a section of the stem is clipped off and observed; native honeysuckle will not have a hollow pith through the middle of the stem, while invasive honeysuckles will.

KISMA Management Practices

Invasive honeysuckle is a highly aggressive species that produces copious amounts of seeds and saplings and can quickly take over an understory. Here at KISMA, invasive honeysuckle is another major invasive species that we have at multiple sites. It’s important to revisit sites as honeysuckle seeds are viable in the ground for multiple years, and removing all seedlings is critical. KISMA prioritizes the removal of seed trees and satellite populations first to prevent the further spread of invasive honeysuckle. Steps to remove them include:

1. hand-pull small seedlings and saplings
2. for stems too large to hand-pull, use a weed wrench to loosen the roots. After the roots are loosened, the tree should be easy to remove with hand pulling.
3. if the tree is too large for the weed wrench, cut the tree a few inches above the ground and cover it with a thick trash bag. To secure the bag to the stump, use a zip tie, spread the bag over the soil around the stump, and weigh the bag down with rocks or wood. Leave the bag in place for two growing seasons. This smothering technique will prevent stump sprout regeneration and kill the root mass.

Note: It's very important to remove seeds and seed-bearing trees first, as this is the main reproduction strategy of invasive honeysuckles.

Native Alternatives

Great native alternatives to invasive honeysuckles include native cherries, such as pin cherry (Prunus pensylvanica) and chokecherry (Prunus virginiana). Serviceberry (Amelanchier sp.) is also a wonderful alternative providing a well-needed food source to native wildlife. Other species like highbush cranberry (Viburnum trilobum) and other native shrub species are also great.

KISMA Area Images of the Species

Native Lookalikes

A native lookalike for invasive honeysuckles is American fly honeysuckle (Lonicera canadensis). American fly honeysuckle is one of our earliest flowering understory shrubs with pale yellow flowers that hang down. Notably, American fly honeysuckle has stems that are not hollow, unlike the invasive species of honeysuckle listed above.