Principal source: Pacific Islands Ecosystems at Risk, (PIER, 2002)
Compiler: Scott Henderson, Charles Darwin Research Station, Galapagos Islands & IUCN/SSC Invasive Species Specialist Group (ISSG)
Review: Scott Henderson (Charles Darwin Research Station, Galapagos Islands).
Publication date: 2010-08-16
Recommended citation: Global Invasive Species Database (2024) Species profile: Psidium guajava. Downloaded from http://www.iucngisd.org/gisd/speciesname/Psidium+guajava on 02-11-2024.
Physical: Extensive stands of young trees can be controlled through burning, as cutting results in regrowth with multiple stems (Morton 1987). On the other hand, in the Galapagos, burning, manual cutting and even bulldozing have resulted in exacerbated invasion. Regeneration from underground parts by suckering limits the effectiveness of manual control (Cronk and Fuller 2001).
Chemical: Guava is sensitive to foliar applications of triclopyr, dicamba and 2,4-D at 1 lb/acre, and to cut surface applications of concentrates of these herbicides; very sensitive to basal bark treatments of triclopyr ester and 2,4-D ester at 2% and 4% respectively, in diesel or crop oil; very sensitive to soil-applied tebuthiuron at 2 lb/acre. Very sensitive to very-low volume basal bark applications of 20% triclopyr ester product in oil. A small-leafed shrubby form of guava appears to be tolerant of foliar applied herbicides but sensitive to tebuthiuron (PIER).
Biological: Goats and sheep can be used for control, as they graze leaves and strip the bark. Goats have been successfully used in Hawai‘i.