Roots, Shoots, Fruits & Flowers: Japanese Clematis, Large Milkweed Bug, & Bacterial Wet Wood


Closeups of Japanese clematis flowers. Photo: Wisconsin Master Gardeners.

Japanese Clematis

Earlier in the month before we had to isolate ourselves from each other, Naomi brought a vine with only its foliage and no bloom to the AgCenter for identification. She enjoys this plant and wanted to know its name.

This is a type of clematis, and it has several different names, Japanese clematis, or sweet autumn clematis, or sweet autumn virgin’s bower. According to the Wisconsin Master Gardener website, “Because Japanese clematis aggressively self-seeds and has escaped cultivation in many parts of the US to invade forest edges, rights-of-way and areas along streams and roads, it is often considered an invasive species – particularly in the East and Midwest – and is no longer recommended as a landscape plant in many states.”

If Japanese clematis is a problem in a landscape, the University of Florida recommends these treatments, “Current chemical-control methods include foliar applications of triclopyr amine (e.g. 2-3% Garlon 3A) and triclopyr ester (e.g. 15% Garlon 4 oil) for basal-bark applications. Either formulation, applied to cut stump, is effective in controlling the plant. Foliar application of glyphosate (e.g. 3% Roundup) provides good, but short-term control. For basal-bark applications, be sure to locate where the vine is rooted. Clematis vines will sometimes grow up one tree, trail back down to the ground, and climb up another tree.”


A large milkweed bug. Photo: Texas A&M University.

Large Milkweed Bug

Carol brought in an insect for identification before the “shelter in place” instructions. This specimen went to the Louisiana State Arthropod Museum (LSAM) from which came this report, “Identification: Oncopeltus fasciatus - large milkweed bug”.

This insect is harmless to people, and it feeds on milkweed seed. Because it feeds on milkweed seed, it has a bitter taste to predators. Its colorful appearance is meant to discourage predators from feeding on this insect.


Pruning wounds with bacterially infected sap and enabling mold to grow. Photo: Keith Hawkins

Bacterial Wet Wood

Steve from Singer asked AHA to make a site visit to examine some fruit trees. After arriving, Steven pointed to an apple tree with pruning wounds and a lot of fungal growth.

The condition affecting this tree is called bacterial wet wood or slime flux according to a page from the LSU AgCenter’s website. Many different types of bacteria can cause this problem in many species of trees. The bacterial rarely kill the tree, but this condition makes for a smelly, unattractive tree and for secondary fungal infections.

“The best way to manage the disease is to protect the tree from environmental stresses including drought, soil compaction, overwatering and mechanical damage. Special care should be taken while mowing and weed eating.” A search of other extension web pages confirms there is no treatment to eliminate this condition.

If you want to contact Roots, Shoots, Fruits and Flowers, please send your questions and pictures to Keith Hawkins, Area Horticulture Agent (AHA), 337-463-7006 or Also, you can be on the “green thumbs” email list by emailing your request to the address above.

“This work has been supported, in part, by the USDA National Institute of Food and Agriculture, Renewable Resources Extension Act Award, Accession Number 1011417.”

3/30/2020 6:49:02 PM
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