A Thief in Our Woods: Asian Bush Honeysuckle

Appearances can be deceiving, especially in the plant world. Take the invasive Asian bush honeysuckle for example. With its bright colored berries, fragrant flowers and ability to stay green longer than most native species, Asian bush honeysuckles seem like the perfect plant for any landscape.

Yet, nothing can be further from the truth. This pretty little shrub is nothing but a thief stealing the water, nutrients and light from our native plants.

Asian Bush Honeysuckles

Bush honeysuckles are shrubs that can grow anywhere between 6 and 15 feet tall. The shrub is characterized by paired berries, paired tubular flowers and hollowed branches. They are also hard to miss as bush honeysuckles are the first to leaf out in the spring and the last to lose their dark green leaves in the fall. Although Asian bush honeysuckles are similar, each specie varies in one way or the others.

According to the Invasive Plant Species Assessment Work Group, or IPSAWG, there are four different varieties of Asian bush honeysuckle found in Indiana:

Amur honeysuckle - Lonicera mackii - white tubular flowers; bright red berries; found in 81counties in Indiana; originated from China

Bella's honeysuckle - Lonicera X bella - white to deep red tubular flowers; found in 65 counties (mostly in the northern part of the state)

Morrow's honeysuckle - Lonicera morowii - white tubular flowers; red berries; found in 62 counties in Indiana; originally from Japan

Tatarian honeysuckle - Lonicera tatarica - pink tubular flowers; dark red berries; only found in Henry County; originated from Russia

Location information found on CAPS & 100 Years of Change in the Distribution of Common Indiana Weeds by William & Edith Overlease (2002).

How Did They Get Here and Why We Want Them Gone

As with many invasive plants - like autumn olive and garlic mustard - Asian bush honeysuckles were planted with good intentions. According to Purdue Extension forester, Ron Rathfon, these invasives were planted throughout the state in the 1950's and 1970's. Several state forestry and wildlife agencies promoted bush honeysuckle as a great ornamental in home and urban landscaping. It was also touted as a great way to control erosion, and to create wildlife cover and food sources.

Unfortunately, there were wrong. Asian bush honeysuckles are problematic due to their rampant and aggressive growth behavior. They form dense thickets that block sunlight, and prevent anything from growing underneath it. Thus native plants are pushed out, while new shoots are able to grow due to the bush’s high shade tolerance.

Birds that consume and disperse its berries helped spread the bush as well. Though it was touted as a great food and cover source to wildlife, it did the opposite. Wildlife was left more exposed to predators, and the berries contained no nutritional value to the birds that ate them. Serious bush honeysuckle invasions also impede tree regeneration which allows a limited succession in infested forests. There are even some species that can release chemicals into the soil that are toxic to other plants. These attributes has caused much concern for many state and local agencies, all which are determined to get rid of as much of Asian bush honeysuckles as they can.

Managing and Controlling Asian Bush Honeysuckle

There are several factors you should consider before you take an ax to those Asian bush honeysuckles in your backyard.

For one thing, do not cut down your bush honeysuckles. Cutting down will not kill the plant, but just may encourage more growth as bush honeysuckles sprout quite easily from their roots.

Size of the shrubs and the size of the invasion should be taken into consideration. If the infestation is of seedlings and small plants, then pulling out or removing seeds by hand will work out well. Trying that with a bigger bush will only wear you out.

With larger infestations, IPSAWG recommends herbicide to get rid of bigger Asian bush honeysuckles. A 1% solution of glyphosate (i.e. Roundup) can be sprayed on the foliage or applied by sponge. With well-established stands, cut the bush to ground level and spray or paint the stumps with 20-30% solution of glyphosate or an 8% solution of triclopyr (i.e. OrthnoBrush B-Gon concentrate). As always, make sure to read and follow the label instructions carefully when using herbicides. Also, use a method that would prevent damage to nearby native plants.

For More Information

Invasive Plant Species Assessment Group - IPSAWG - Asian Bush Honeysuckle Fact Sheet

Midwest Invasive Plant Network - MIPN - Their mission: to reduce the impacts of invasive plant species in the Midwest. Print out their Nursery Wallet Cards to mark down what invasive species are being sold in your local nursery or greenhouse.

Cooperative Agricultural Pest Survey - CAPS - a listing of Indiana's "Most Wanted" invasive plant pests including the Asian Bush Honeysuckle

MIPN's Why Should I Care about Invasive Plants brochure

Nature picture credits: Photo © Patrick Breen (Tatarian honeysuckle & Morrow's honeysuckle); Photo © TNC (Asian bush honeysuckle berries).