 |
|
|
 |
|
|
|
|
|
Psidium cattleianum (tree, shrub)  |
|
|
Management Information
Preventative measures: A Risk Assessment of Psidium cattleianum for Hawai‘i and other Pacific islands was prepared by Dr. Curtis Daehler (UH Botany) with funding from the Kaulunani Urban Forestry Program and US Forest Service. The alien plant screening system is derived from Pheloung et al. (1999) with minor modifications for use in Pacific islands (Daehler et al. 2004). The result is a score of 18 and a recommendation of: "Likely to cause significant ecological or economic harm in Hawai‘i and on other Pacific Islands as determined by a high WRA score, which is based on published sources describing species biology and behaviour in Hawai‘i and/or other parts of the world."
Physical: Because of the huge quantities of seed that are dispersed by feral pigs, and other exotic invasive species, feral species management is a practical and necessary first step in strawberry guava management. Manual and mechanical control measures work reasonably well and are recommended where practical. Seedlings and saplings originating from seed can be uprooted. Uprooted plants may resprout or re-root in areas with greater than 2000mm of rain/year or drier areas after prolonged rain, especially if the plants are set on the ground. Manual and mechanical methods are less effective on root sprouts.
Chemical: A number of effective chemical control measures have been developed. Strawberry guava is sensitive to picloram, dicamba, glyphosate, and triclopyr. It has been shown that undiluted picloram (Tordon 22K) is highly effective on strawberry guava as a cut stump treatment. Tordon 22K was used at Hawai‘i Volcanoes but discontinued because of unfavourable effects on non-target plants. It was replaced by Tordon RTU, which was nearly as effective, but less harmful to surrounding vegetation. Undiluted dicamba (Banvel) proved to be highly effective in a cut surface treatment. Additionally, undiluted glyphosate (Roundup) has proven to be effective using a ""hack and squirt"" method. Resource Managers in Hawai‘i found undiluted triclopyr ester (Garlon 4) to be effective as a cut-stump treatment, with 80% of plants dead and 90% of treated plants without resprouts after 21 months. A frill application of undiluted triclopyr amine (Garlon 3A) was somewhat less effective, with 11 of 20 stems dead and all trees defoliated after 21 months. Fifty percent Garlon 4 and 3A were about 50% effective. A major drawback of cut-stump treatment methods in very wet areas (>5000mm rainfall/yr) was resprouting of slash from cut stump and wood fragments from felling larger trees. Garlon is recommended because of its lack of mobility and relatively short half-life, 4-6 weeks. In addition, the research is more thorough and definitive on control methods for Garlon than other herbicides.
Biological: Biological control is the only feasible long-term management strategy for strawberry guava. However, until recently, biological control has been perceived as unfeasible because common guava, grown commercially in Hawai‘i, is a congener of strawberry guava. Biological control is being reexamined. Several insects defoliate strawberry guava in its natural range, it is possible that insect biological control agents could be found that do not attack common guava. Memoranda of agreement has been concluded between the University of Hawai‘i and two Brazilian Universities to locate species attacking strawberry guava and not common guava. It is thought that highly specific insect pests can be found because common guava and strawberry guava are sympatric in their natural range.
Location Specific Management InformationFrench Polynesia (Polynésie Française) 
Decree No. 65 CM of January 23, 2006 presents a list of 35 invasive plants declared to be "Species that threaten biodiversity", one of which is Psidium cattleianum. These plants are subject to a ban on new imports, propagation and planting, and prohibition of transfer from one island to another of any whole plant, fragment of plant, cutting, fruit or seed. Raoul Is. (New Zealand)
This species has been subject to an eradication programme on Raoul Island since 1973, and is ranked Category A(i) - known to have the potential to significantly alter the vegetation of Raoul Island. Raoul Island has been divided into 13 weeding blocks for the purpose of controlling and eradicating alien plants since 1972, which make up 64% of the vascular plant flora on Raoul Island. These are divided into active plots which are searched at least twice a year, and null plots which are searched at least once every two years. Grid searching is used to examine the areas with easier access, while steep cliffs are searched using binoculars or a telescope. This is carried out when plants such as Caesalpinia decapetala are in flower (June-November). Aerial surveillance is carried out periodically which has been useful in identifying flowering trees such as Senna septemtrionalis, mature vines of Passiflora edulis or trees of Olea europaea ssp. cuspidata. The initial knockdown phase involved for most species the cutting of mature individuals and painting of stumps with herbicides, or scattering herbicide granules around them. Blanket spraying was used to treat dense, inaccessible infestations. Subsequent searches involve the removal of any seedlings or young plants found. If a mature plant is found, the fruit is removed for burning, the stem is cut and herbicide applied. Information regarding the eradication programme is stored on an Access database. More than 250 Psidium cattleianum individuals were removed between1997 and 2000. The importation of alien plants to Raoul Island is prohibited.
Management Resources/Links
2. Daehler, C.C; Denslow, J.S; Ansari, S and Huang-Chi, K., 2004. A Risk-Assessment System for Screening Out Invasive Pest Plants from Hawaii and Other Pacific Islands. Conservation Biology Volume 18 Issue 2 Page 360.
Summary: A study on the use of a screening system to assess proposed plant introductions to Hawaii or other Pacific Islands and to identify high-risk species used in horticulture and forestry which would greatly reduce future pest-plant problems and allow entry of most nonpests. 3. Fleischmann, K., Edwards, P.J., Ramseier, D. and Kollmann, J. 2005. Stand structure, species diversity and regeneration of an endemic palm forest on the Seychelles, African Journal of Ecology 43(4). 4. Hivert, J. 2003. Plantes exotiques envahissantes - Etat des méthodes de lutte mise en oeuvre par l'Office National des Forêts à La Réunion. ONF Réunion.
Summary: Synthèse des méthodes de lutte employées par l'ONF à la Réunion contre une vingtaine de plantes exotiques envahissantes. 5. Huenneke, L.F., Vitousek, P.M. 1990. Seedling and clonal recruitment of the invasive tree Psidium cattleianum: Implications for management of native Hawaiian forests, Biological Conservation 53(3): 199-211. 7. Kueffer, C. and Mauremootoo, J., 2004. Case Studies on the Status of Invasive Woody Plant Species in the Western Indian Ocean. 3. Mauritius (Islands of Mauritius and Rodrigues). Forest Health & Biosecurity Working Papers FBS/4-3E. Forestry Department, Food and Agriculture Organization of the United Nations, Rome, Italy. 9. Mauremootoo, J. R. unpublished. CBD case study - guava in Mauritius.
Summary: This article reviews the status of Psidium in Mauritius, its impact on native biodiversity, the efforts being made to control the species and possible future avenues for management. 11. Normand, F. 2002. The Strawberry Guava: a new Fruit Species for Humid Areas in Reunion Island,ISHS Acta Horticulturae 575. 13. Stone, C. P., Smith, C. W. and Tunison, J. T. 1992. Alien Plant Invasions in Native Ecosystems of Hawaii. Management and Research. University of Hawaii Cooperative Park Studies Unit: 1-887.
Summary: This large and comprehensive volume covers general features of invasive species biology, case studies of invasive species management in the US, the pest status & autecology of some of the major invasives in Hawaii, methods used for the control. 14. Strahm, W. A. 1999. Invasive species in Mauritius: examining the past and charting the future. In Invasive Species and Biodiversity Management. Kluwer Academic Publishers: 325-347.
Summary: This article reviews the history of introduced animals and plant in Mauritius and their effects on the indigenous flora & fauna. Management measures are reviewed & illustrated with case studies. Future prospects for invasive species management are discuss Results Page: 1
|
|
|
|
 |
|
