Hawaii Invasive Species Council

Miconia calvescens                                           

 

 

Photo credit: DLNR (above) Starr Environmental (below)

 

DESCRIPTION:

• Miconia is a fast growing weedy tree that reaches 13-50′ in height. 
• It has large leaves that average 3′ long and 1′ wide, and are dark green and felty above, with a distinctive “leaf within a leaf” vein pattern. 
• The underside of the leaves are purple.                                                                                                                                                                      
• It produces dark purple fruits that are 1/3″ in diameter and contain hundreds of seeds.

IMPACTS:

• Miconia trees grow quickly and close together, shading out nearly all other forest plants with their large oval leaves. 
• Their shallow root system can cause increased erosion and landslides.
•  Miconia quickly matures, producing fruit after three to four years and flowers and fruits several times a year. 
• Plants produce ten to twenty million seeds a year, which can remain viable for twelve years and possibly longer. 
• Miconia harms our watersheds by forming an umbrella over the canopy, reducing the amount of rainwater that can seep into the ground. 
• Miconia has destroyed 70% of Tahiti’s native forest.                                                                                                                                              
• Miconia destroys habitat for native birds. 

ERADICATION & CONTROL METHODS:

• Physical control methods include removing smaller saplings by hand. Mature trees can be cut back, but will regrow from stumps and must be cut back repeatedly.                                                                                                                                                                    
• As the plant can grow back easily from cuttings, contacting your local invasive species committee about disposal is recommended.
• Pesticides used include oil-based triclopyr products. Always read the label thoroughly before using any pesticide. Ensure you are using the product in accordance with the label to abide by the law. Directions: “The herbicide is dripped in a continuous line around the base of the Miconia trunk. No bark needs to be removed, but it is a good idea to wipe away the moss and any soil that is present.” (BIISC)  
• A potential biocontrol agent is “eulelasia chrysipee.”   It is a small butterfly whose caterpillar feeds on the leaves of the miconia. 
• Miconia calvescens is a KISC Target Species, a OISC Target Species, and a MISC Target Species.

WHAT YOU CAN DO:

•  Decontamination is extremely important to reduce the risk of spreading Miconia. Hikers, biker and any vehicle or construction equipment can easily transport miconia’s long-lived, tiny seeds that are caught in tread, dirt, clothing, and mud. 
• Thoroughly clean all vehicles, boots, clothing, equipment, and anything else exposed to mud before moving out of the Miconia infestation zone. 
• If you spot Miconia on Oʻahu: Do NOT pull or cut down the plant. OISC will properly remove and dispose of the plant to prevent spreading seeds and re-sprouting. Please report miconia to OISC. Send photo and location to [email protected] or text 808-286-4616. You can also call OISCʻs office at 808-266-7994.      
• If you spot Miconia on Kauai: KISC is actively controlling this species. Sightings of this pest should be reported immediately to 643pest.org If you suspect that you have any of KISC target species on your property, KISC will survey and if confirmed, will remove it for free.