Richard,John2025-09-112025-09-112007https://www.suaire.sua.ac.tz/handle/123456789/6980Dissertationa potential invasive plant in Amani Nature Reserve (ANR). In order to provide information toward efforts to combat alien invasive plants in ANR, the research was undertaken to study the abundance and distribution of Castilla elastica in the Reserve. To locate definite plots in the Amani Botanical Garden originally planted with Castilla, reports The point-centred quarter method was used for the determination of the relative abundance of Castilla and other constituent species of the canopy in the study area. Furthermore, the population characteristics of Castilla were studied and its Weed Risk Assessment (WRA) was carried out. The distribution of Castilla in the reserve falls within the altitudinal range of 380 significant difference (F3.16 = 28.2, P< 0.001) in density of Castilla between the four levels of forest disturbance in the study area. The density of Castilla in areas of high disturbance was approximately 192 stems/ha, 98 stems/ha in moderately disturbed, 63 stems/ha in plantation forest and 26 stems/ha in areas of low disturbance. The diameter distribution of Castilla suggests an expanding population with 55% seedlings, 30% saplings, 10% juveniles, 3% young trees, and 2% mature trees. The individuals in a population does not significantly (Z-test, P 0.05) influence the number of regenerants produced. The total score obtained from the WRA of Castilla in ANR is 11 and this shows that Castilla has a risk of becoming invasive in the on the botanical survey in ANR by Greenway (1934) and Hones (1963) were used. sex ratio of Castilla in ANR is female-biased and presence or absence of male Castilla elastica an exotic tree species to Tanzania was reported as m to just over 600 m asl. There was reserve. Therefore, this calls for close monitoring and control of its population growth in ANR.enAlien plantPanama rubber (castilla elastica)Amani Nature ReserveTree speciesThesis