Shrub Honeysuckles (Lonicera sp.)

Invader Type: 

Control

Mechanical Control: 

Hand pull: Any time of year when the ground is soft, especially after a rain, hand pull small plants by the base of the stem. Be sure to pull up the entire root system. Hang from a branch to  prevent re-rooting. For larger plants, use a Weed Wrench™. Continue to monitor the area every year for new seedlings.

Cut stump: Cut plants back in the fall or winter. Wrap a few layers of burlap or thick plastic over the stump and tie tightly with twine or rope. Check covered stumps periodically and cut back any new growth.

 

Chemical Control: 

Cut stump:  Cut the plant 4 inches above the ground. Use a drip bottle to apply a 18-21% glyphosate solution to the stump within one hour of cutting. This is best done in late summer through winter when plants are transporting resources to their root systems.

Low volume foliar spray: This method is used for dense populations and best left to a contractor. In the fall, when native plants are losing their leaves, spray a 2% glyphosate or triclopyr solution on the entire leaf surface of the plant. In order to avoid drift to native plants, spray only on calm days

Photos

Photos: 

Description

Identification: 

There are four invasive species of bush honeysuckle that invade Vermont forests. These include Amur honeysuckle (Lonicera maackki), Morrow’s honeysuckle (Loniceria morrowii), Tartanian honeysuckle, (Lonicera tatarica) and Bell’s honeysuckle (Lonicera x bella).  All of them are deciduous shrubs with opposite, egg shaped leaves, fragrant flowers, and red or orange-red berries. They can grow to be 15 feet high.

The four invasive species are difficult to distinguish from one another. The most important thing to know is how to tell it apart from native honeysuckle. All of the invasive honeysuckle species found in Vermont have a hollow pith. Native honeysuckle has a solid white pith and is not typically as robust of a shrub as the invasives.

 

Check out this short video on how to identify honeysuckle in the field

Reproductive Strategy / Lifecycle: 

Shrub honeysuckles reproduce mainly by seed but some vegetative re-sprouting can occur in established populations. Plants mature between 3-5 years of age. Each plant produces thousands of berries as fruit, and each fruit contains 2-6 seeds. Seeds can remain viable for 3-5 years.

Dispersal: 

Seeds are mostly dispersed by birds that eat the berries. Despite providing the bird with feeling full, shrub honeysuckle berries provide little to no nutritional value for birds.

Habitat: 
Shrub honeysuckles can be found in forests, abandoned fields, open woodlands, and along roadsides and forest edges. They can also tolerate wet soils and invade places such as bogs, fens and lake shores. They are relatively shade tolerant but are more vigorous in full sun.
References: 

Photos: (c) C. Evans River to River CWMA; (c) S. Leicht University of Connecticut; (c) L. Mehrhoff Univeristy of Connecticut; (c) M. Frey The Presidio Trust; (c) J. Randall The Nature Conservancy.

Threat

Ecological Threat: 
  • When songbirds build nests in non-native honeysuckle they suffer a higher predation rate than when their nests are built in native shrubs such as arrowwood (Viburnum dentatum). This is because honeysuckle stems are sturdier and closer to the ground — raccoons, skunks and other predators can easily scramble up the stems.
  • Forest regeneration is severely impacted by honeysuckle infestations. The shrubs form dense colonies in the understory, outcompeting native shrubs and trees.
  • Sunlight can no longer reach the forest floor, reducing the diversity and abundance of native wildflower and fern populations.