Non-native plants present serious management problems in many preserves. Strawberry guava Psidium cattleianum (Myrtaceae), a small tree and aggressive invader of tropical areas, is rapidly spreading through many Hawaiian forests including those of the two US national parks in Hawaii. Feral pigs and non-native birds disperse Psidium seeds; pigs also create soil disturbances that may enhance the tree's spread. Our study of guava's reproductive biology focussed on its dependence on non-native animals. We found that the abundantly produced seed germinated rapidly under a wide range of conditions, without scarification. Psidium seedlings occur on the same substrates as do native seedlings, usually on undisturbed sites. Both seedlings and clonally produced suckers are common, but suckers contribute greater leaf areas. Guava's clonal growth may partially explain its success in dominating native forests. Apparently germination and establishment do not depend on animal dispersal, or on disturbances created by pigs; thus, control of the plant cannot rest entirely on control of non-native animals.
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics
- Nature and Landscape Conservation