Chinese tallow tree (Triadica sebifera (L.)) has become a threat to Southern United States forestlands because of the rapid colonization. To explore the growth rate of tallow, numerous growth models were constructed with destructive sampling method from oak-gum-cypress (Quercus/Liquidambar styraciflua/Taxodium distichum) and longleaf/slash pine (Pinus taeda/ Pinus echinata) forests in southern Mississippi. Moreover, stem profile was also fitted with segmented profile models: Max and Burkhart (1976), Cao (2009) modified Max and Burkhart, and Clark et al. (1991). Numerous results showed that: 1) diameter at breast height, volume and biomass of tallow grew faster in oak-gum-cypress forest while height grew faster with DBH in Longleaf/Slash pine forest; 2) the stem of tallow was generally sturdy in oak-gum-cypress forest while it was slender in longleaf/slash pine forest; however, there was no significant difference between them. Growth and taper models provide a tool for managers to estimate future stocking of tallow tree.

The coastal plain of the southeastern United States is historically wet pine savannahs, prairie, and hardwoods. However, many exotic species have invaded this area and become a serious threat to native forest ecosystems. Among those exotic species, Chinese tallow (Triadica sebifera) has become one of the most pervasive tree species in the southern coastal states, including Alabama, Mississippi, Louisiana, and Texas. Therefore, to understand the distribution and spread mechanisms has become important in the management and control of Chinese tallow in the southeastern United States. In this research, distribution and spread mechanisms of Chinese tallow were studied at multiple spatial scales, including regional, landscape, and stand. Effects of predisposing (community and landscape features) and inciting (natural disturbance and human activities) factors on Chinese tallow invasion had been evaluated by using a comprehensive data set (field data and Forest Inventory and Analysis data) and spatial statistical models. Results indicated that propagule pressure of Chinese tallow is the main force driving tallow dispersal at different spatial scales. Predisposing and inciting factors such as natural disturbances, anthropogenic disturbances, forest types, forestland ownerships, and landscape features are significantly related to the spread of Chinese tallow at different spatial scales. Regionally, Chinese tallow initially started to spread from southern Texas and Louisiana to the northeastern portion of the Gulf Coastal area. At landscape and stand scales, Chinese tallow has commonly invaded from edges of forests and habitats such as roads and firebreaks. Inciting factors, including hurricanes/storms and prescribed fires, could accelerate the spread of Chinese tallow at different spatial scales, especially in habitats that have previously been invaded. Compared to pine forests, it is easier for Chinese tallow to invade bottomland hardwood forests at the regional scale. The efficient dispersal distance of tallow seeds is 250-300 m, and its distribution is affected by the microtopography in forest stands. Management of Chinese tallow invasion should be focused at selected scales, such as landscape and stand levels, because of variations of site conditions.

Understanding the ecology of invasive species is vital to curb the homogenizing of ecosystems, yet the pollination mechanisms of the Chinese tallow tree (Triadica sebifera) in its introduced habitat remain ambiguous. This study examines self-pollination, wind pollination, and flower-visiting insects of tallow in a bottomland hardwood forest and Longleaf pine savannah in the U.S. Gulf South. These data suggest that self-pollination and airborne pollination are possible, but likely rare occurrences, although the possibility of apoxisis was not investigated. Seed production in exclusion experiments was significantly less than in open-pollinated flowers, and wind dispersal of tallow pollen dropped to essentially zero 8 meters from the source. Results show that tallow is primarily bee pollinated, with external pollen loads of Apis, Melissodes, and halictids visiting at similar rates, and Xylocopa species visiting less frequently. The researchers believe that to date, this is the first study of the pollination mechanisms of T. sebifera in its introduced range and recommend further study to understand the ecology of this destructive invasive species.

Knowledge of sex allocation trade-offs with tree growth in insect-pollinated woody plants is limited, particularly in invasive plants. This study examined patterns of growth and reproductive investment in a North American invasive plant species, Triadica sebifera, I hypothesized that the energy limitations of smaller trees may result in the production of more male reproductive structures that are energetically less costly. Diameter at breast height was a significant predictor of seed and catkin mass and regression can describe these relationships across sites. Seed and catkin mass were positively correlated across sites. The relationship between the seed mass:catkin mass ratio and DBH was not significant, nor was seed mass:catkin mass and total investment. Results showed a significant positive relationship between total reproductive investment and tree size across sites. Seed mass:catkin mass ratio and reproduction investment showed substantial variation among individual trees of similar size within sites.

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