Japanese Knotweed

Common Name of Species: Japanese Knotweed

Scientific Name of Species : Fallopia japonica (Houtt.) Ronse Decr.

Where is it native?  What kind of environment is it found in its native habitat?

Japan. In deep shade, high temperatures, high salinity, and drought and near water sources, such as along streams and rivers, in low-lying areas, waste areas, and around old home sites.

What are the effects of this invasive species on the ecosystem?

• spreads quickly to form dense stands and can exclude native vegetation
• alter natural ecosystems by leaving masses of dead stems behind
• leaves river beds vulnerable to erosion and floods

What impacts do you think it will have?

• survival of severe flooding means rapid-reproduction
• crowds out other species and kills off native vegetation
• brings new organisms and forces out the natives

What are the best ways to remove this species?

• continuous mowing for about 2-3 years maybe more
• “carpeting” or covering it with a tarp
• non-stop digging and cutting out the base (like for years and years) to get to the rhizomes
• MUST  remove the roots!!!!!!
• if you choose, pour (CAREFULLY) 5 ml of undiluted herbicide down the stem

Effects of herbicide

• can eventually accumulate in drinking water and food
• when you ingest a certain level, it causes toxic symptoms which can lead to cancer, asthma, endocrine system disruption, and harmful affects on babies
• causes harmful affects to bees and insects

Is it found at EMS?  So far no knotweed has been discovered in our forests.