Windbreak benefit to potato yield in tropical north Australia

A study was conducted on the Atherton Tablelands of tropical north Australia to quantify the benefit of a 18-month-old windbreak to the production of potato (Solanum tuberosum L.). In the leeward side, wind velocity and potato yield were measured at various distances from the windbreak. Wind direction on the study site was also monitored. Non-linear modeling was used to describe the relationship between potato yield and distance from the windbreak. The definite integral was applied to the developed model to calculate the net increase percentage of potato yield. Wind velocity was greatly reduced by the windbreak, and potato yield was increased by 6%. It appears that fitting non-linear models is a useful method to determine an accurate net increase of crops from windbreaks

Preliminary results of a provenance trial of Eucalyptus camaldulensis in a dry tropical area of north Australia

A provenance trial of Eucalyptus camaldulensis was conducted in the Burdekin region of tropical north Queensland, Australia. Six provenances ranging from subtropical south Queensland to tropical north Queensland, each with and without mulch at planting, were assessed for their survival, height and DBH. There was a significant difference in survival, height and DBH among the provenances tested at age three years. However, the effect of mulch on these three parameters was insignificant. It appears that for the harsh environments of dry tropical north Queensland, provenances of tropical origins are more suitable than those from subtropical areas

Suitability of Eucalyptus grandis and E. microcorys as windbreak species in tropical northern Australia

A study was conducted on the Atherton Tablelands of tropical north Australia to compare the suitability of Eucalyptus grandis and E. microcorys for forming windbreaks. Wind speed was measured at various distances from the leeward side of each of the E. grandis and E. microcorys windbreaks, both 13 years old and consisting of five rows of trees. The species were measured for their height, diameter at breast height (DBH), crown length (between the rows) and width (along the row), number of branches per tree, bole length (height to the lowest branch) and windbreak porosity. The E. microcorys windbreak had a uniform porosity both vertically and horizontally while the E. grandis windbreak had uneven porosity with some obvious gaps at the base (up to 8 m from the ground). E. grandis was significantly taller and longer in bole length but lower in number of branches per tree than E. microcorys at age 13 years. Wind speed was reduced more by the E. microcorys windbreak than by the E. grandis windbreak. E. microcorys appears to be a suitable species for windbreaks whereas E. grandis does not

Inventories and significance of the genetic resources of an African mahogany species (Khaya senegalensis (Desr.) A. Juss.) assembled and further developed in Australia.

The forest tree species Khaya senegalensis (Desr.) A. Juss. occurs in a belt across 20 African countries from Senegal-Guinea to Sudan-Uganda where it is a highly important resource. However, it is listed as Vulnerable (IUCN 2015-3). Since introduction in northern Australia around 1959, the species has been planted widely, yielding high-value products. The total area of plantations of the species in Australia exceeds 15,000 ha, mostly planted in the Northern Territory since 2006, and includes substantial areas across 60-70 woodlots and industrial plantations established in north-eastern Queensland since the early-1990s and during 2005-2007 respectively. Collaborative conservation and tree improvement by governments began in the Northern Territory and Queensland in 2001 based on provenance and other trials of the 1960s-1970s. This work has developed a broad base of germplasm in clonal seed orchards, hedge gardens and trials (clone and progeny). Several of the trials were established collaboratively on private land. Since the mid-2000s, commercial growers have introduced large numbers of provenance-bulk and individual-tree seedlots to establish industrial plantations and trials, several of the latter in collaboration with the Queensland Government. Provenance bulks (>140) and families (>400) from 17 African countries are established in Australia, considered the largest genetic base of the species in a single country outside Africa. Recently the annual rate of industrial planting of the species in Australia has declined, and R&D has been suspended by governments and reduced by the private sector. However, new commercial plantings in the Northern Territory and Queensland are proposed. In domesticating a species, the strategic importance of a broad genetic base is well known. The wide range of first- and advanced-generation germplasm of the species established in northern Australia and documented in this paper provides a sound basis for further domestication and industrial plantation and woodlot expansion, when investment conditions are favourabl

An Integrated Assessment of the Horticulture Sector in Northern Australia to Inform Future Development

The horticulture sector in northern Australia, covering north of Western Australia (WA), Northern Territory (NT), and north Queensland (QLD), contributes $1.6 billion/year to the Australian economy by supplying diverse food commodities to meet domestic and international demand. To date, the Australian Government has funded several studies on developing the north’s agriculture sector, but these primarily focused on land and water resources and omitted an integrated, on-ground feasibility analysis for including farmers’/growers’ perspectives. This study is the first of its kind in the north for offering a detailed integrated assessment, highlighting farmers’ perspectives on the current state of the north’s horticulture sector, and related challenges and opportunities. For this, we applied a bottom-up approach to inform future agriculture development in the region, involving a detailed literature review and conducting several focus group workshops with growers and experts from government organisations, growers’ associations, and regional development agencies. We identified several key local issues pertaining to crop production, availability of, and secure access to, land and water resources, and workforce and marketing arrangements (i.e., transport or processing facilities, export opportunities, biosecurity protocols, and the role of the retailers/supermarkets) that affect the economic viability and future expansion of the sector across the region. For example, the availability of the workforce (skilled and general) has been a challenge across the north since the start of the COVID-19 pandemic in 2020. Similarly, long-distance travel for farm produce due to a lack of processing and export facilities in the north restricts future farm developments. Any major investment should be aligned with growers’ interests. This research highlights the importance of understanding and incorporating local growers’ and researchers’ perspectives, applying a bottom-up approach, when planning policies and programs for future development, especially for the horticulture sector in northern Australia and other similar regions across the globe where policy makers’ perspectives may differ from farmers

Estimation of Fruit Load in Australian Mango Orchards Using Machine Vision

The performance of a multi-view machine vision method was documented at an orchard level, relative to packhouse count. High repeatability was achieved in night-time imaging, with an absolute percentage error of 2% or less. Canopy architecture impacted performance, with reasonable estimates achieved on hedge, single leader and conventional systems (3.4, 5.0, and 8.2 average percentage error, respectively) while fruit load of trellised orchards was over-estimated (at 25.2 average percentage error). Yield estimations were made for multiple orchards via: (i) human count of fruit load on ~5% of trees (FARM), (ii) human count of 18 trees randomly selected within three NDVI stratifications (CAL), (iii) multi-view counts (MV-Raw) and (iv) multi-view corrected for occluded fruit using manual counts of CAL trees (MV-CAL). Across the nine orchards for which results for all methods were available, the FARM, CAL, MV-Raw and MV-CAL methods achieved an average percentage error on packhouse counts of 26, 13, 11 and 17%, with SD of 11, 8, 11 and 9%, respectively, in the 2019–2020 season. The absolute percentage error of the MV-Raw estimates was 10% or less in 15 of the 20 orchards assessed. Greater error in load estimation occurred in the 2020–2021 season due to the time-spread of flowering. Use cases for the tree level data on fruit load was explored in context of fruit load density maps to inform early harvesting and to interpret crop damage, and tree frequency distributions based on fruit load per tree

1962

Turf on the Launching Pad (page 1) Turf management Club News (3) Education, Experience and Attitude (4) A Blade of Grass (5) Picture - Professor Lawrence S. Dickinson (6) Picture - Thomas Mascaro - Banquet Speaker (7) Planting Trees on the Golf Course (8) Two-Way Radios (8) Greens Mowing Procedure (9) Watering and Topdressing as Related to Poa annua Infestations (10) Picture - Stockbridge Majors in Turf Management (12) Picture - Graduates of Winter School for Turf Managers - 1962 (13) Review of Season\u27s Pests by Joseph Troll (A-1) Today\u27s Trends in Golf Course Development by Col. Harry C. Eckoff (A-3) Breeding and Selection of Fine Turf Grasses by Dr. B. R. Anderson Penncross Bentgrass by J. Dutch(A-13) Poa annua by Alexander Radko (A-16) Velvet Bent by Jesse DeFrance (A-19) Vegetative Creeping Bentgrasses by Fred Grau (A-21) Modification of SOils for Green Construction & Top Dressing by Prof. H. B. Musser (A-27) Soil COmpaction by Donald Waddington (A-32) Irrigation Practices and the Need of Basic Research by Prof. Edward PIra (A-36) Water Sources by Z. Mills (A-39) Athletic Field Maintenance by Thomas Mascaro (A-41) Planning the Landscape Around the House by Prof. Harold Mosher (A-43

Small Scattered Fragments Do Not a Dwarf Make: Biological and Archaeological Data Indicate that Prehistoric Inhabitants of Palau Were Normal Sized

Current archaeological evidence from Palau in western Micronesia indicates that the archipelago was settled around 3000–3300 BP by normal sized populations; contrary to recent claims, they did not succumb to insular dwarfism