ICFR KZN Midlands Regional Interest Group Field Day

Transcription

1 ICFR Midlands Field Day Thursday 20 th November 2014 Wartburg Church & Windy Hill Thanks are extended to Mondi for sponsoring the catering

2 ICFR KZN Midlands Regional Interest Group Field Day Date: 20th November 2014 Venue: Wartburg Lutheran Church, Wartburg Time: 08h30 for 09h00 08h30 Meet for tea and coffee PROGRAMME Indoor Presentations 09h00 Welcome Shaun Henderson Masonite 09h10 Mapping the risk of the myrtle rust Puccinia psidii in South Africa: A bioclimatic approach Ilaria Germishuizen ICFR 09h35 Update on plantation pests and diseases in South Africa Jolanda Roux FABI 10h00 The effect of spacing Eucalyptus dunnii seedlings at different ages and densities Marnie Light ICFR 10h25 A comparison between two hybrid breeding strategies employed in the production of Eucalyptus grandis x Eucalyptus urophylla Gert van den Berg Mondi 10h50 11h30 11h55 12h20 12h50 TEA The development of time study standards for Southern Africa - the benefit to harvesting and silviculture operations Long-term wattle fertiliser trial: Some early 6th rotation results Community involvement in research and small grower projects LUNCH Simon Ackerman Louis Titshall Terry Everson ICFR ICFR UKZN 14h00 Field visit to nutrient depletion trial site Steven Dovey ICFR 15h30 End of Field Day ICFR KwaZulu-Natal Midlands Field Day Page 2

3 Mapping the risk of the myrtle rust Puccinia psidii in South Africa: A bioclimatic approach Ilaria Germishuizen ilaria.germishuizen@icfr.ukzn.ac.za Institute for Commercial Forestry Research, P.O. Box , Scottsville, Pietermaritzburg, 3209 The pathogen Puccinia psidii (Myrtle rust) was first detected in South Africa in May 2013 in the KwaZulu- Natal South Coast. The Myrtle rust represents potentially a serious threat to Eucalyptus plantations and to native species of the family Myrtaceae by causing a rust disease. This presentation focuses on the development of a risk model to identify areas where the environmental conditions required for the establishment of a viable population of P. psidii in South Africa are met, and it is part of a collaborative research project led by Prof Jolanda Roux (FABI) and involving the ICFR (Dr Ilaria Germishuizen and Dr Ryan Nadel) and the Department of Agriculture, Forestry and Fisheries (DAFF) of Australia (Dr Jeoff Pegg). The risk model uses bioclimatic variables as predictors to geographically map the potential distribution of P. psidii. Climatic variables and thresholds were defined based on available literature describing the climatic requirements of the pathogen where viable populations are established (Blum and Dianese, 2001; Booth et al., 2000; Glen et al., 2007; Kriticos et al., 2013; Ruiz et al., 1989). Variable predictors selected for the model were based on 1 minute by 1 minute historical climatic grids (Schulze 2007). Seasonal and annual risk maps were developed showing areas of potential high (RH 80% and Tmin 18 and 22 C) and medium (RH 70% and Tmin 10 C) risk (Figure 1). The potential risk to Eucalyptus plantations was evaluated by overlaying the current areas under forestry to the potential geographic range of P. psidii. Most of the areas currently under forestry (about 80%) are within the geographic range suitable to P. psidii, indicating a potential threat to the health of Eucalytpus plantations in South Africa. The current distribution range of the 4 native species of the family Myrtaceae also broadly overlay with P. psidii suitable range, suggesting a potential threat to the regional biodiversity asset. ICFR KwaZulu-Natal Midlands Field Day Page 3

4 Figure 1. Potential Puccinia psidii high (RH 80% and Tmin 18 and 22 C) and medium (RH 70% and Tmin 10 C) risk areas in South Africa. References Blum LEB, Dianese JC Patterns of urediniospores release and development of rose apple rust. Pesquisa Agropecuaria Brasileira 36; Booth TH, Old KM, Jovanovic T A preliminary assessment of high risk areas for Puccinia psidii (Eucalyptus rust) in the Neotropics and Australia. Agriculture Ecosystems & Environment 82: Glen M, Alfenas AC, Zauza EAV, Wingfield MJ, Mohammed C Puccinia psidii: a threat to the Australian environment and economy a review. Australasian Plant Pathology 36; 1-16 Kriticos JD, Morin L, Leriche A, Anderson RC, Caley P Combining a climatic niche model of an invasive fungus with its host species distributions to identify risks to natural assets: Puccinia psidii sensu latu in Australia. Plos 8(5): 13p Ruiz RAR, Alfenas AC, Ferreira FA Effect of temperature, light and inoculum source on teliospore and urediniospore production of Puccinia psidii. Fitopatologia Brasileira 14: Schulze RE South African atlas of climatology and agrohydrology. Water Research Commission, Pretoria, RSA, WRC Report 1489/1/06 ICFR KwaZulu-Natal Midlands Field Day Page 4

5 Update on plantation pests and diseases in South Africa Jolanda Roux*, Alistair McTaggart and Brett Hurley Tree Protection Co-operative Programme (TPCP), Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, South Africa, Pest and disease problems continue to challenge the South African forestry industry. In the past year the industry has seen the appearance of a number of new insect pests in the country, an outbreak of a rust disease of Acacia mearnsii, the appearance of pitch canker disease of Pinus species in the KwaZulu- Natal Midlands and Limpopo Province and the cossid moth in the Karkloof area. In 2012 some farmers in the KZN Midlands became aware of an unknown disease problem on A. mearnsii. This disease (Figure 1) rapidly became a serious concern to the industry, with many farmers experiencing epidemics resulting in tree stunting and in some cases death. The cause of the disease has been confirmed as being a rust fungus in the genus Uromycladium, most closely related to U. alpinum. Research is underway to more accurately identify the fungus to species level in order to gain more information on its possible origin. Together with the ICFR and other stakeholders, studies on the epidemiology of the pathogen will commence in 2015, so as to more accurately apply chemical treatment to reduce the impact of the pathogen. Pitch canker of mature Pinus species, caused by the fungus Fusarium circinatum, was first reported from the Karkloof area in 2012, from a trial planting of P. greggii. These trees were ten years of age and showed typical symptoms of resin exudation (Figure 2e) from the main stems of trees. In 2014 the disease was confirmed in a nearby commercial stand of P. greggii. Most recently, pitch canker disease was confirmed on four and seventeen year-old P. patula trees in the Limpopo Province.The blue gum chalcid, Leptocybe invasa, is continuing to result in significant damage to eucalypt plantings country wide (Figures 2a,b). Infestations are leading to tree stunting and in some cases death. In 2012 a biological control agent, Selitrichoides neseri, was released at more than 400 sites in South Africa. Monitoring of these sites have shown that S. neseri has successfully established at most sites, and have started moving naturally to adjacent areas. For many years the cossid moth, Coryphodema tristis, was known from Eucalyptus nitens, only from the Lothair area. In 2014, this insect was, however, found on E. nitens in the Karkloof. It is specific to E. nitens, resulting in wood loss as a result of the tunnelling action of the larvae of the moth. Great success has been made in developing a pheromone to attract and trap the moth and this is currently being tested extensively under field conditions. Two new incursions of important Eucalyptus insect pests were detected in Gauteng in These are the gall wasp Ophelimus maskeli (Figure 2d) and the psyllid Spondyliaspis sp. (Figure 2c). Currently these insects are only known from Gauteng, but experience with L. invasa and the red gum lerp psyllid, ICFR KwaZulu-Natal Midlands Field Day Page 5

6 Glycaspis brimblecombii, suggest that they may very rapidly spread countrywide. Through collaborations with researchers in other countries, the TPCP has already accessed biological control agents to manage some of these pests. These are currently being tested in our laboratories in Pretoria. Management of tree pests and diseases requires a team effort and participation by all in the industry. We encourage all farmers and foresters to report any unknown/unusual tree health problems to the TPCP. In this way new problems can be detected in a more timely fashion. We also encourage all in the industry to not move diseased plant material between regions and to only apply insecticides in areas where no biological control agents have been released. For any pest and/or disease information please contact: Jolanda Roux (Extension and Diagnostics): Cellular , jolanda.roux@fabi.up.ac.za, office Izette Greyling (Extension and Diagnostics): Cellular , izette.greyling@fabi.up.ac.za Darryl Herron (Diagnostic Clinic): Work /9, darryl.herron@fabi.up.ac.za Brett Hurley (Insect Biological control): Work /9, brett.hurley@fabi.up.ac.za Jeff Garnas (Entomology): Work /9, jeff.garnas@fabi.up.ac.za ICFR KwaZulu-Natal Midlands Field Day Page 6

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9 The effect of spacing Eucalyptus dunnii seedlings at different ages and densities Marnie Light 1 and Tracy Newmarch 1 marnie.light@icfr.ukzn.ac.za Institute for Commercial Forestry Research, P.O. Box , Scottsville, Pietermaritzburg, 3209 Increasing the growing space for seedlings or cuttings in the nursery has the potential to produce planting stock with slightly different morphological characteristics. Seedlings that are more widely spaced tend to be shorter and have a lower sturdiness ratio than seedlings that are grown closer together. This, in turn, could result in seedlings that are more robust and able to better survive transplanting to the field. To test the effect of spacing seedlings at different ages and different densities, a nursery trial was conducted at Mountain Home Nursery using Eucalyptus dunnii seedlings raised in Unigro-98 containers. Spacing treatments involved spacing the Unigro-98 inserts to 50% (checker-board pattern) at 10 and 14 weeks after sowing. A further treatment involved spacing the seedlings to 50% at 10 weeks, and respacing them to 25% at 17 weeks (summarised in Table 1). Table 1: Summary of treatments used in the nursery trial to investigate the effect of spacing E. dunnii seedlings. Treatment Code First spacing to 50% Second spacing to 25% 1 No spacing wk 10 weeks wk 14 weeks wk-17wk 10 weeks 17 weeks Spacing the seedlings at different ages (Treatments 1-3) resulted in shorter seedlings, with lower sturdiness ratios, compared to the non-spaced control treatment. However, it was noted that the growing media in the containers for the treatments which were spaced was generally dryer than in the non-spaced containers. This may have had a negative impact on the growth of the spaced seedlings and is an aspect that would need to be further investigated to fully understand the impact of spacing on seedling growth. ICFR KwaZulu-Natal Midlands Field Day Page 9

10 A comparison between two hybrid breeding strategies employed in the production of Eucalyptus grandis x Eucalyptus urophylla Gert J van den Berg 1, Steve Verryn, Paxie W Chirwa and Francois van Deventer 1 gert.vandenberg@mondigroup.co.za Mondi Limited, P O Box 12, Hilton, 3245 In order to combine the good survival, disease tolerance and higher wood density of E. urophylla with the rapid early growth of E. grandis, hybrids of the two species have been produced in South Africa. Currently two main hybrid breeding strategies are used to test hybrid material. Both strategies make use of general combining ability (GCA) to select elite parent trees from pure species of main populations. These elite parent trees are then use for controlled pollinations to generate hybrid seed. The seed is then tested either with or without a hybrid seedling testing phase, i.e.: - In a series of hybrid seedling progeny trials from which individuals are selected based on four year growth results and then tested as clones in clonal trials, or - Established in hedges from which cuttings are produced and tested as clones in clonal trials (without going through a seedling testing phase). The purpose of this study is to do a comparative study between these two strategies. The key focus areas of this study are to compare genetic parameters and phenotypic correlations between pure species parents, E. grandis x E. urophylla hybrid seedlings and E. grandis x E. urophylla hybrid clones that derived from these parents and some these results will be presented. Data from a total of seven E. urophylla and nine E. grandis main population trials, seven E. grandis x E. urophylla hybrid seedling progeny trials and 29 E. grandis x E. urophylla clonal trials are included in the analysis. Future work will utilise these results to structure and model an alternative theoretical strategy to optimise genetic gain and production. ICFR KwaZulu-Natal Midlands Field Day Page 10

11 The development of time study standards for southern Africa: The benefit to harvesting and silviculture operations Simon Ackerman Institute for Commercial Forestry Research, P.O. Box , Scottsville, Pietermaritzburg, 3209 The development of Standard Time Study guidelines for the South African Forest industry to bring its operational productivity, productivity control systems and higher-level research in line with international standards. There is a move locally and internationally from traditional manual or motor manual operations to high-tech mechanised systems where planning and productivity are of the utmost importance. Being able to establish sound methods to conduct time studies and develop productivity standards increases the competitiveness of the industry, improves productivity and increases enterprise (contractor) viability. Support for this initiative has been established, and full scale roll out of operation based standard development is being planned and being carried out. ICFR KwaZulu-Natal Midlands Field Day Page 11

12 Long-term wattle fertiliser trial: Some early 6th rotation results Introduction Louis Titshall Institute for Commercial Forestry Research, P.O. Box , Scottsville, Pietermaritzburg, 3209 Project Team: Greg Fuller, Michael Buthelezi, Nkosinathi Kaptein In the late 1940 s a number of factorial fertiliser experiments were implemented to help develop and refine fertiliser application recommendations for wattle production. In most cases combinations of nitrogen, phosphorus, potassium and lime were tested. One of the trials (C2 at Bloemendal) was reimplemented for a further 5 rotations. The 6th rotation was felled in early 2014 and this presentation provides some of the early results of various growth parameters assessed. Experimental overview 34 factorial arranged in a quasi-latin square confounded in nine rows by nine columns. Table 1 presents a summary of historical fertiliser regimes used. Table 1: Overview of fertiliser regimes used for each rotation of the long-term wattle fertiliser trial at Bloemendal. Nitrogen (as Ammonium sulphate) Phosphorus (as Single Super Phosphate) Rotation 1 to 3 Rotation 4 Rotation 5 Rotation 6 kg ha -1 (g tree -1 ) 0, 25, 50 (0, 10.5, 21) None 0, 20, 40 (0, 8, 16) None Potassium (as KCl) 0, 60, 120 (0, 12.5, 25) 0, 30, 60 (0, 6, 12) None Lime Planting notes Dates 0, 5.6, 11.2 (as agricultural lime) Line sowing, thinned to ± 1400 R1: 1951 to 1961 R2: 1961 to 1971 R3:1971 to , 5.6, 11.2 (as dolomitic lime) None Seedling planted in pits, thinned to ± 1500 None Seedling planted in pits, never thinned (± 2400) Variates assessed DBH (converted to basal area), total height, volume, stocking, wet bark yield. Soil samples and bark samples for analysis also collected but not reported here. ICFR KwaZulu-Natal Midlands Field Day Page 12

13 Results No significant residual interaction effects (p > 0.05). No significant main effects of N or K (p > 0.05). Some significant main effects of P and Lime (p < 0.05): o Positive P responses for BA, height, volume. o Negative lime response for BA, volume, stocking and wet bark yield. Some Preliminary Thoughts Liming negatively affects production for extended periods Do not lime wattle plantations. Evidence of residual P may offer opportunity to lower P fertilisation rates in the future. Past and current results do not indicate any benefit to nitrogen fertiliser. Re-application of potassium may be necessary to main nutrient balance. Acknowledgements SAWGU for funding, Gary Behn and staff for land and operational assistance, past and current ICFR staff involved with trial. ICFR KwaZulu-Natal Midlands Field Day Page 13

14 Community involvement in research and small grower projects Terry Everson University of KwaZulu-Natal, Private Bag X01, Scottsville, Pietermaritzburg, 3209 Community based natural resource management (CBNRM) is increasingly seen as an approach to encourage better resource management. Experiences in a rehabilitation project in the Upper Thukela have shown that local communities and stakeholders must play an important part in the process if success is to be achieved. The first step in involving communities in a project is gaining the approval of the relevant tribal authorities in the project area. This is also an opportunity to find out what other projects are taking place and develop partnerships with relevant NGO s, CBO s, government and research organizations. Communication is the key component in this process. Monthly partner s meetings enable communication between organizations on issues such as report backs on project activities and finances, co-ordination of meetings and transport and sharing experiences. By the second year of the project the community members were facilitating the partners meeting, taking minutes and submitting written reports on activities of the various committees. Since the success of CBNRM performance depends on innovative community-based organizations, the next step is to develop institutional capacity of the community to participate in the project. This may entail working with existing committees or developing new committees voted in by the community. Finding committed people is a long term process which is unlikely to be achieved in short term projects of one to two years, but is feasible in the longer term small grower s projects. Selection of community members for project activities is often politically biased if payment is involved. This may be avoided by involving community members in the process and specifying the minimum criteria for selection of project teams. One of the main lessons from the project was that social and technological issues must be integrated when developing solutions to environmental problems. From the start of the project the community were involved in decision making on topics ranging from short term planning (e.g. date of next meeting, catering) to complex issues (e.g. development of land use management plans, selecting work teams, establishing a committee). This has led to the ownership of the project by the community. One of the challenges for small grower projects is making people aware of the benefits over the long term. Building capacity of the participants in project activities (e.g. growth measurements) or involving school groups in education programmes will encourage growers to assume responsibility for the project. ICFR KwaZulu-Natal Midlands Field Day Page 14

15 Multisite nutrient depletion trials Steven Dovey Institute for Commercial Forestry Research, P.O. Box , Scottsville, Pietermaritzburg, 3209 Site nutrient supply must be maintained if the productivity of successive rotations is to be sustained. Nutrients are supplied to trees from soil reserves that are at risk of becoming depleted through continuous nutrient removals associated with harvesting and residue management. The ability of forestry soils to resist and recover from nutrient loss is poorly understood. There is no link between laboratory-determined nutrient pool size estimates, soil supply potential and the ability of trees to take up and efficiently utilise nutrients. The ability of sites to naturally recover or be ameliorated is also poorly understood. A research project was initiated in 2013 that aims to develop knowledge on the nutrient loss that key soils can withstand until tree growth becomes nutrient limited. Nutrient removal is carried out through intensive biomass removal. The aim is to induce nutrient-related growth decline in the tree crop on soils derived from six major parent materials and to relate the decline to laboratory based indicators of soil nutrient supply. A second phase of this project will be to test the ability for soils to recover naturally or through fertilisation. Six research trials were initiated between 2012 and These are situated on soils with properties to create a range in risk of soil fertility decline (Table 1). The studies utilise a combination of high density planting, heavy coppicing and annual harvesting and complete residue/litter (forest floor) removal to induce rapid soil nutrient loss. Nutrient removal through complete tree and residue removal is compared with treatments that retain or replace nutrients (namely residue retention and fertilisation). After the lower nutrient supply limits have been detected or identified, the field trials will be operationally re-planted at conventional spacing to test the ability of each site and soil to recover from nutrient depletion naturally or through fertilisation. A treatment-related growth response has already been detected at the first site (NDS1) after two harvest cycles. A reduction in tree growth and depression of top-soil nutrient status has occurred with residue and litter removal. Fertilisation and residue retention has maintained tree growth rates. ICFR KwaZulu-Natal Midlands Field Day Page 15

16 Table 1: General site and 0-20 cm soil information for the six nutrient depletion study (NDS) sites Trial NDS1 NDS2 NDS3 NDS4 NDS5 NDS6 Apr Planted March 2013 Nov 2012 Jan 2014 Nov 2013 Nov Lithology Aeolian sand Natal Group sandstone Site Dukuduku Windyhill Kwambo (SQF) Aeolian sand Gabbro Granite Shale Glen Eland Glen Eland Region Zululand Midlands Zululand Central Central Midlands Species Egxu Egxu Egxu Egxn Egxn Egxu MAP (mm) MAT ( C) Altitude (m) Silt % nd Clay % nd Sand % nd ph (KCl) nd ph(h 2O) nd N % nd nd P (ppm) nd K + cmol c kg nd Ca 2+ cmol c kg nd Mg 2+ cmol c kg nd Na + cmol c kg nd S-value cmol c kg nd OC (WB) % nd Ex.Acid cmol c kg nd nd = no data (awaiting lab results) Clan ICFR KwaZulu-Natal Midlands Field Day Page 16