PDF《Invasive plant species on Kosrae,》

i and French Polynesia, respectively. Cinnamomum verum (cinnamon), found to be very invasive in American Samoa and elsewhere. It is present on Pohnpei. Clidemia hirta (Koster'

s curse), a serious problem species in Hawai'

i and in other locations. In Micronesia it is only present in Palau, but would be a serious problem if introduced as it grows well in the shade of closed forests. Coccinia grandis (ivy or scarlet gourd), a smothering vine that is showing potential for serious damage to the forests of Saipan. The vines climb over trees and form such dense cover that the forest underneath is completely shaded out and destroyed. It is also invasive in Guam and Hawai'

i and a horticultural variety is present on Pohnpei. The proximity of the plant on Pohnpei and Guam poses a threat to Kosrae.

3 Two rubber trees, Funtumia elastica (African rubber tree) and Castilla elastica (Panama rubber tree), species that have proven very invasive in Samoa. While not known to be present in Micronesia (Castilla elastica is present in Hawai'

i) and thus posing a lesser threat, their invasive nature makes these species prime candidates for prompt eradication if found. Eichhornia crassipes (water hyacinth), present on Guam and Pohnpei and a threat to Kosrae'

s rivers and wetlands. The Hyptis species, H. capitata, H. pectinata and H. suaveolens. Kosrae is presently free of these invasive plants. H. capitata is present on Pohnpei, though, and could pose a threat to Kosrae. Miconia calvescens (the purple plague), which has caused serious damage to the ecosystem of Tahiti and had spread to several other islands in French Polynesia. It has also escaped in Hawaii and is the subject of an intensive and costly eradication effort there. Recently it was discovered in Queensland, Australia. It is an attractive garden plant and might be introduced this way or as tiny seeds on shoes or used equipment. A number of grass species, including: ? Melinis minutiflora (molasses grass), a species that is both invasive and causes a serious fire hazard. It has fostered the establishment of fire regimes on many islands where it has been introduced. It is present on Guam, and is thus a threat to other Micronesian islands. ? Pennisetum setaceum (fountain grass), another grass that is a major problem in Hawai'

i. It is also present on Guam. ? Imperata cylindrica (cogon grass), known as a very invasive species and reported to be present on Guam. ? A number of other grass species of various degrees of invasiveness, including Andropogon gayanus, Andropogon glomeratus, Andropogon virginicus, Brachiaria mutica, Brachiaria subquadripara, Cenchrus brownii, Cenchrus ciliaris, Chloris barbata, Cynodon dactylon, Digitaria insularis, Digitaria violascens, Echinochloa polystachya, Hymenachne amplex- icaulis, Hyparrhenia rufa, Ischaemum rugosum, Ischaemum timorense, Panicum maximum, Panicum repens, Paspalum dilatatum, Paspalum fimbriatum, Paspalum paniculatum, Paspalum urvillei, Pennisetum clandestinum, Rhynchelytrum [Melinis] repens, Schizachyrium condensatum, Setaria pallide-fusca, Setaria palmifolia and Sorghum halepense. Grasses are easily introduced as contaminants in imported seed, imported sand and gravel or on used machinery. Mimosa invisa (giant sensitive plant) and Mimosa pudica (sensitive plant) are both absent from Kosrae but present on Pohnpei and Guam. Mimosa invisa is a particularly nasty plant as it is covered with thorns and forms dense tangles that are difficult to walk through. Mimosa pudica, a smaller plant with only small prickles, can form dense mats. Kosrae is at high risk for invasion by both these plants.