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Coastal Swamp Oak Forests (CSOF) dominated by the species Casuarina glauca are an Endangered Ecological Community under state and Commonwealth legislation in Australia. These forests have suffered significant historic declines due to changes in land use and hydrological modification. Although they have a limited contemporary extent (~320 to over 500 km 2 ) along the east coast of Australia, CSOF represent part of a much larger range of supratidal forested wetlands in Australia, which include wetlands vegetated by the more broadly distributed genus Melaleuca . For the first time, in this chapter we estimated aboveground and 1 m-depth belowground organic carbon (C org ) stocks in CSOF (mean ± SD: 143 ± 61 Mg C org /ha and 241 ± 136 Mg C org /ha, respectively) across six study sites in temperate and subtropical Australia. Variations in aboveground C org stock are explained by differences in the stature and structure of forests, while belowground C org stocks appear more reflective of within- and among-estuary variations in geomorphic evolution. These early findings show that C org stocks in CSOF are within the range of values reported for mangrove, saltmarsh and seagrass ecosystems. Our data provide a foundation for future research efforts to determine the carbon sequestration potential of CSOF, and their amenability to management interventions which seek to reverse past losses and contribute to climate change mitigation.

In 1935, cassiterite was discovered on the Melaleuca plain and the deposits were exploited by a succession of small-scale operations. In 1941, the lease was purchased by Charles King who worked the deposit alone until 1945 when he was joined by his son Deny King. In the summer of 1973, Peter and Barbara Willson and their young family sailed into Port Davey for a holiday and returned to Hobart having purchased part of the King lease and other leases in the area. As a qualified mining engineer, Peter and Barbara used modern alluvial mining, processing and smelting techniques to produce tin from the peat soils of Melaleuca. Peter started mining at Melaleuca in 1974 with just a pan, pick, shovel and wheelbarrow. The mining operation was gradually expanded with purchases of heavy machinery: a backhoe, excavator and dump trucks. At Melaleuca, cassiterite is found in the gravel sands that lie between bedrock and the overlying peat topsoil. Strip mining proved to be the most economic and practical method of winning the cassiterite-bearing coarse gravel sands. The processing plant used a gravity circuit to separate the cassiterite from the gravel sands and was designed and built entirely by Peter. He also designed and built his first smelter, a blast furnace in 1992 and constructed the reverberatory furnace in 1997. The smelter product still contained some impurities. To improve the quality of the product, two separate refining processes were undertaken. The mine workings encompass a large part of the Melaleuca plain but only a small percentage is still visible from the ground or air due to diligent rehabilitation. In 2011, Peter and Barbara agreed to relinquish the majority of their mining leases to the Tasmanian Wilderness World Heritage Area., In 1935, cassiterite was discovered on the Melaleuca plain and the deposits were exploited by a succession of small-scale operations. In 1941, the lease was purchased by Charles King who worked the deposit alone until 1945 when he was joined by his son Deny King. In the summer of 1973, Peter and Barbara Willson and their young family sailed into Port Davey for a holiday and returned to Hobart having purchased part of the King lease and other leases in the area. As a qualified mining engineer, Peter and Barbara used modern alluvial mining, processing and smelting techniques to produce tin from the peat soils of Melaleuca. Peter started mining at Melaleuca in 1974 with just a pan, pick, shovel and wheelbarrow. The mining operation was gradually expanded with purchases of heavy machinery: a backhoe, excavator and dump trucks. At Melaleuca, cassiterite is found in the gravel sands that lie between bedrock and the overlying peat topsoil. Strip mining proved to be the most economic and practical method of winning the cassiterite-bearing coarse gravel sands. The processing plant used a gravity circuit to separate the cassiterite from the gravel sands and was designed and built entirely by Peter. He also designed and built his first smelter, a blast furnace in 1992 and constructed the reverberatory furnace in 1997. The smelter product still contained some impurities. To improve the quality of the product, two separate refining processes were undertaken. The mine workings encompass a large part of the Melaleuca plain but only a small percentage is still visible from the ground or air due to diligent rehabilitation. In 2011, Peter and Barbara agreed to relinquish the majority of their mining leases to the Tasmanian Wilderness World Heritage Area.

Australian tea tree oil (TTO) and its extract terpinen-4-ol (T4O) are found to be effective in moderating demodex-related diseases. Their possible effects are lowering the mite counts, relieving the demodex-related symptoms and modulating the immune system especially the inflammatory response. This review summarizes the topical treatments of TTO and T4O in human demodicosis, their possible mechanism of actions, side-effects and potential resistance in treating this condition. Although current treatments other than TTO and T4O are relatively effective in controlling the demodex mite population and the related symptoms, more research on the efficacy and drug delivery technology is needed in order to assess its potential as an alternative treatment with minimal side-effect profile, low toxicity and low risk of demodex resistance.Copyright © Cambridge University Press 2018.

Australian tea tree oil (TTO) and its extract terpinen-4-ol (T4O) are found to be effective in moderating demodex-related diseases. Their possible effects are lowering the mite counts, relieving the demodex-related symptoms and modulating the immune system especially the inflammatory response. This review summarizes the topical treatments of TTO and T4O in human demodicosis, their possible mechanism of actions, side-effects and potential resistance in treating this condition. Although current treatments other than TTO and T4O are relatively effective in controlling the demodex mite population and the related symptoms, more research on the efficacy and drug delivery technology is needed in order to assess its potential as an alternative treatment with minimal side-effect profile, low toxicity and low risk of demodex resistance.Copyright © Cambridge University Press 2018.

The family Myrtaceae is known for its high foliar terpene concentrations as well as significant qualitative and quantitative variation in foliar terpenes between taxa, populations and individuals. To date, few studies have investigated the genetic and biochemical processes, which underlie this variation, much of which is known to be under genetic control. Differences in yield are both ecologically and commercially important and a better understanding of its basis will allow a greater understanding of Australian ecosystems as well as improve commercial viability of essential oil industries. Over the past decade a good understanding of the genes involved in terpene biosynthesis has developed in other species and several important regulatory steps have been identified. Much of this work has been done in transgenic plants, so our understanding at a molecular level is strong. Nonetheless, it remains unclear if these processes are transferrable to wild populations, or indeed how ecologically important quantitative variation in terpenoids arise and are maintained in natural ecosystems. In this review we will summarize what is known about terpene biosynthesis and the control of flux through the terpene biosynthetic pathways. We will then argue that this platform of work provides a great resource for Myrtaceae, as well as other plants, to identify candidate genes that control flux through the biosynthetic pathways and how this will inform further studies into the ecological implications of quantitative variation of terpenes. Work into terpene biosynthesis would also provide a framework to improve the profitability of essential oil crops.

Medicinal tea tree (Melaleuca alternifolia) leaves contain large amounts of an essential oil, dominated by monoterpenes. Several enzymes of the chloroplastic methylerythritol phosphate (MEP) pathway are hypothesised to act as bottlenecks to the production of monoterpenes. We investigated, whether transcript abundance of genes encoding for enzymes of the MEP pathway were correlated with foliar terpenes in M. alternifolia using a population of 48 individuals that ranged in their oil concentration from 39 -122 mg x g DM(-1). Our study shows that most genes in the MEP pathway are co-regulated and that the expression of multiple genes within the MEP pathway is correlated with oil yield. Using multiple regression analysis, variation in expression of MEP pathway genes explained 87% of variation in foliar monoterpene concentrations. The data also suggest that sesquiterpenes in M. alternifolia are synthesised, at least in part, from isopentenyl pyrophosphate originating from the plastid via the MEP pathway.

Melaleuca ferruginea is newly described, M. nervosa subsp. crosslandiana is reduced to M. nervosa, and an amended identification key is provided for the M. leucadendra species group.

Melaleuca ferruginea is newly described, M. nervosa subsp. crosslandiana is reduced to M. nervosa, and an amended identification key is provided for the M. leucadendra species group.

Riparian vegetation varies according to hydrogeomorphic processes operating across different scales over two didmensions: transversely (across-stream) and longitudinally (parallel to stream). We tested the hypothesis that vegetation patterns reveal the scale and direction of underlying processes. We correlated patterns of dominant woody vegetation with environmental variables at 28 sites located within four geomorphologically distinct regions along the length of the South Alligator River catchment of Kakadu National Park, northern Australia. Across the catchment there existed a strong transverse boundary between upland savanna vegetation and two zones of riparian vegetation: Melaleuca-spp.-dominated closed-forest vegetation along stream channels and mixed open-woodland vegetation adjacent to closed forest. We surmise that there is hierarchic constraint on smaller-scale catchment processes due to fire incursion into the riparian zone and access to water during the dry season. Within the closed-forest zone, vegetation did not vary transversely, but did longitudinally. Riparian woodlands also varied longitudinally, but in the upper reaches varied independently of stream variables. By contrast, in the lower reaches woodland was strongly correlated with stream variables. The observed pattern of weak transverse linkages in headwaters but strong linkages in lower reaches is analogous to models developed for in-stream patterns and processes, particularly the river continuum and flood-pulse concepts.

Melaleuca quinquenervia (Cav.) Blake, common names melaleuca, cajeput, or punk tree, is native to the Australian region. Trees were first planted in Southern Florida early in the 20th century. Starting in the late 1940s, melaleuca was planted by U.S. Army Engineer personnel at Lake Okeechobee, Florida, to serve as wind barriers and to provide protection for the levees surrounding the lake. The trees have now spread to wetland habitats and were found by a 1979 survey to grow along 88.5 km (53.1 miles) of the 175km (105 miles) of levee road and to cover approximately 96.8 ha (242 acres) in these perimeter stands (Stocker l982a). Additionally, Stocker found that 'in the lake proper, melaleuca is found in approximately 420 ha (1,050 acres), where it offers as isolated individuals and as dense colonies (heads) up to 0.6 ha (1.5 acres) in size.' This distribution of trees was approximately 0.3 percent of the lake acreage.

Adame, M. F., Reef, R., Wong, V. N., Balcombe, S. R., Turschwell, M. P., Kavehei, E., ... & Ronan, M. (2020). Carbon and nitrogen sequestration of Melaleuca floodplain wetlands in tropical Australia. Ecosystems, 23(2), 454-466. https://doi.org/10.1007/s10021-019-00414-5

No species or common name noted. See WA Herbarium's Florabase (florabase.calm.wa.gov.au), A listing of the entire Rica Erickson archive (MN 1740) is available by clicking on the link above.