Invasiveness
Guava is considered invasive in some regions, which may be due to its allelopathic effects on native species (Smith, 1998). It is potentially detrimental to native forest species in the Galapagos Islands (Mauchamp, 1997; Cronk et al., 1995). It is invasive in acacia forests and grasslands of Hawaii, where it has been proposed to use goats to control it because they feed on guava bark (Adrian et al., 2012; CABI, 2013).
Agro-pastoral and agro-silvo-pastoral systems
Guava has a positive environmental impact in some environments. In Costa Rica, guava is a valuable part of Brachiaria brizantha pastures (Villanueva et al., 2008). In Gujarat (India), guava trees have been planted in association with Leucaena leucocephala, buffel grass (Cenchrus ciliaris) and African stylo (Stylosanthes fruticosa) in agro-silvo-pastoral systems to increase productivity and reclaim eroded, degraded and compacted soils with gullies and rocky parts (Raturi et al., 1993).