• Ash dieback in Ireland – A review of European management options and case studies in remedial silviculture

      Short, Ian; Hawe, Jerry; Woodland Trust NI; COFORD; Teagasc (Society of Irish Foresters, 2018)
      Ash dieback, caused by Hymenoscyphus fraxineus, is developing rapidly across the island of Ireland. Ireland’s ash (Fraxinus excelsior L.) woodlands, particularly first rotation plantations, are quite unique and are at particular risk of very rapid decline. Urgent action is required in order to minimise the economic, ecological and social impact of the disease. However, for this to happen forest owners require guidance regarding potential positive management interventions. This article outlines the wider, mainly European, experience of remedial silviculture. It presents three case studies on existing remedial silviculture trials in Ireland. In the absence of silvicultural research data specific to the evolving situation with ash dieback, this article explores the potential benefits of positive practical actions which may minimise the impact of the disease. Despite the seriousness of the situation, such silvicultural activity may even result in a positive economic outcome. It is hoped that by beginning to document potential mitigatory management options, this paper may bring some reassurance to owners and managers of ashdominated woodlands.
    • Coppice-with-standards: An old silvicultural system with new potential?

      Short, Ian; Campion, Jerry; COFORD (Select Media Ltd, 01/03/2014)
      The last two decades have seen a dramatic increase in the area of broadleaf afforestation in Ireland.Some of these plantations are not performing as well as was expected when planted. This article describes the coppice-with-standards silvicultural system. With the increased demand for fuelwood and greater broadleaf plantation area, some of which may require alternative silvicultural management to the conventional due to poor performance, the coppice–with–standards system has the potential to fulfil many objectives.
    • COST E42 Growing Valuable Broadleaves Silviculture Matrix: An Irish example

      Short, Ian; Bulfin, Michael; Radford, Toddy; European Co-Operation in Science and Technology; COFORD (Teagasc, Oak Park, Carlow, Ireland & Coford, Ireland, 2008)
      The purpose of developing the silvicultural matrix in COST E 42 was to provide a vehicle whereby information on silviculture of valuable broadleaved species could be gathered from as many participating countries as possible. The aim of this matrix is to determine what are considered the optimum silvicultural treatments for each of our target species in countries across Europe. In many cases only one or two countries will have experience of a particular species. Also it must be realised that, for many of the larger countries in Europe, there are different climatic regimes and no single matrix can encapsulate the recommendations for that country. In this case a number of climatic regional matrices would be preferable. For this reason, not all countries felt in a position to contribute a matrix and preferred to provide a narrative discussion on various species. As an illustration of how the matrix can provide a guideline for farmers wishing to plant, the example of ash (Fraxinus excelsior L.) in Ireland is taken. Based on the research we carried out, we developed a set of guidelines to assist farmers in making critical decisions. These guidelines now form the basis for government support to farmers.
    • Morphological and physiological responses of Fagus sylvatica and Quercus robur seedlings to light availability

      Sevillano, Ignacio; COFORD; Teagasc Walsh Fellowship Programme (2016-06)
      The need to develop forest management systems other than clearfelling has resulted in a requirement for improved understanding of the potential of continuous cover forestry (CCF). One suggested method for the conversion of forest stands into CCF systems and for bringing under-performing forests into productivity is thinning in conjunction with underplanting. This study was an attempt to provide information on species suitability for underplanting of two important trees in European forestry: pedunculate oak (Quercus robur L.) and European beech (Fagus sylvatica L.). To determine the morphological, physiological and growth responses of these two species to different light conditions, beech and oak seedlings previously grown at full light for two years were covered by shading nets that provide different shade levels (62%, 51% or 28% of full light) or continued to be exposed to full light. The different shade levels were intended to mimic a range of underplanted conditions and the process of acclimation to shade was studied to provide information on the ecology and adaptation of underplanted seedlings. In addition to the controlled-shade experiment another study to determine the physiological responses of beech natural regeneration to shade was conducted under natural light conditions (from open gaps to closed canopy). Both oak and beech displayed similar acclimation in response to shade for most of the traits investigated. At the plant level, seedling acclimation to shade included higher biomass allocation to above than below-ground parts and greater energy investment on height than diameter growth. At the leaf level, seedlings grown under shade reduced their leaf thickness and photosynthetic rates per unit area and increased their specific leaf area. This increase in specific leaf area seems to be one mechanism that allows seedlings to perform well under shade conditions. Another acclimation to low light conditions was to increase the efficiency of the photosystem II under shade. Photosynthetic rates were higher and leaves were retained for longer in seedlings grown at full light than under shade. Hence, this probably led to a greater growth in the full light than under shade. Despite this greater growth at full light, the results of this study suggest that beech and oak seedlings would be able to acclimate and perform well if underplanted below overstories that reduce the available light to as low as 28% of full light without having any significant adverse effect on the quality of the final crop.
    • Physiological Responses of Fagus sylvatica and Quercus robur Seedlings to Light Intensity

      Sevillano, Ignacio; Short, Ian; O'Reilly, Conor; Grant, Olga M.; COFORD (FESPB/EPSO, 22/06/2014)
      Broadleaf planting has become increasingly important in Ireland over the recent years and light is recognised as one of the main environmental factors affecting stand development, but to date there has been little research on broadleaf responses to light intensity, particularly in Ireland. Continuous cover forestry (CCF) is increasing as an alternative to clear-cutting and uses the control of light to produce plantation benefits. The physiological responses of beech (Fagus sylvatica) and oak (Quercus robur) seedlings to four different shade environments (100%, 62%, 51% and 28% of incident photosynthetically active radiation, PAR) were studied in a shadehouse experiment during the summer of 2013. Light-response curves (only measured in the extreme treatments) differed between beech seedlings of the Control treatment (PAR=100%) and those of the heavy shade treatment (PAR=28%) when PAR > 100 μmol m-2 s-1, while there was little difference for oak between both treatments. Light-response curves generally showed maximum photosynthetic rates (Amax) at 1500 μmol m-2 s-1 in both treatments, and this PAR value was used while measuring stomatal conductance (gs) and water use efficiency (WUE). Significantly higher values of Amax and gs were found in oak than in beech in the 62%, 51% and 28% treatments. There were no significant differences between oak and beech for Amax and gs in the Control treatment or for WUE in the four treatments.
    • Poor performance of broadleaf plantations and possible remedial silvicultural systems - a review

      Hawe, Jerry; Short, Ian; COFORD (Society of Irish Foresters, 2012-12)
      Over the last two decades planting of broadleaves has been part of forest policy. In addition to the provision of a range of ecosystem services, it is intended that this resource will have a direct economic stimulus through the supply of quality hardwood. A number of challenges must be met in order to achieve this objective, particularly as current observations would indicate that many first rotation broadleaf plantations comprise a relatively high proportion of poor quality stems. A literature review has been carried out on the probable causes of poor performance in broadleaf crops. Silvicultural systems to rehabilitate poor quality stands are discussed. Subsequent papers will deal with these silvicultural systems in more detail.
    • Possible silvicultural systems for use in the rehabilitation of poorly performing pole-stage broadleaf stands - Coppice-with-standards

      Short, Ian; Hawe, Jerry; COFORD (Society of Irish Foresters, 2012-12)
      This paper is a review of the coppice-with-standards system, a system that may have potential for the rehabilitation of some poorly performing pole-stage broadleaf stands. The system was once a very common system throughout Europe, producing much needed fuelwood and sawlog. Its decline in Ireland, the UK and elsewhere was primarily due to market forces. This review was conducted because the system may have potential once again due to the recent increased demand for firewood. Coppice-with-standards can provide material of various sizes to supply local demand for fuelwood, pulpwood, fencing material and sawlog. The system also has nonmarket benefits such as amenity and biodiversity values. One disadvantage of the system is that it requires greater silvicultural skill to manage to a high standard. The coppice-with-standards system is being trialled as a means to rehabilitate a poorly performing 19-year-old stand of ash:oak mixture.
    • The potential for using a free-growth system in the rehabilitation of poorly performing pole-stage broadleaf stands

      Short, Ian; COFORD (Society of Irish Foresters, 2013-12)
      This paper is a literature review of the free-growth system, which may have potential for the rehabilitation of some poorly-performing pole-stage broadleaf stands. It involves releasing of a selected number of good quality stems from crown competition as a basis for the final crop. Generally, only stems with crowns adjacent to the potential final crop trees are removed. The aim is to increase diameter growth of the selected stems and thereby shorten the rotation length needed to achieve a given diameter. The treatment may result in a greater incidence of epicormic shoots, particularly in oak (Quercus spp.). To maintain stem quality, epicormics may need to be removed, which may make the free-growth system uneconomic. There is, however, some evidence to believe that this may not be the case. In addition, the free-growth system may also be applicable in species less prone to epicormics, such as ash (Fraxinus excelsior L.) and sycamore (Acer pseudoplatanus L.). The free-growth system may prove to be a useful system for the rehabilitation of poorly performing pole-stage broadleaf stands and, with the advent of Chalara ash dieback (caused by Hymenoscyphus pseudoalbidus V. Queloz et al.) in Ireland, may gain greater use for its ability to reduce rotation lengths.
    • A review of stumping back and case study of its use in the rehabilitation of poorly performing pole-stage sycamore

      Short, Ian; Hawe, Jerry; Campion, Jerry; Byrne, Ricky; COFORD (Society of Irish Foresters, 2015-12)
      First rotation broadleaf plantations present a range of inherent challenges to the achievement of good form and vigour. Where biotic and/or abiotic factors compromise early growth and stem quality, appropriate management interventions to improve these are required. An historical review of “stumping back” literature is presented together with a case-study. The B-SilvRD broadleaf silviculture research project includes a “rehabilitation” strand, whereby innovative measures to improve poorly performing stands of commercial broadleaves are being trialled. One such pilot trial involves a 17year-old sycamore (Acer pseudoplatanus L.) plantation, which had not performed well and required significant intervention to improve its silvicultural and economic viability. This paper reviews the literature on stumping back and presents a case-study with results of three different line thinning/stumping back treatments, including analysis of different light regimes and the impact of light levels on coppice regrowth.
    • Silvicultural Guidelines for the Tending and Thinning of Broadleaves

      Short, Ian; Radford, Toddy; COFORD (Teagasc, Oak Park, Carlow, Ireland & Coford, Ireland, 2008-12)
      This publication provides guidelines for the tending and thinning of ash, alder, sycamore, Norway maple, oak and beech. Some silvicultural procedures to follow during these operations are also provided.
    • Soil carbon stocks in a Sitka spruce chronosequence following afforestation

      Reidy, Brian; Bolger, Thomas; COFORD (Society of Irish Foresters, 2013)
      Increasing concentrations ofCO2 and other greenhouse gases in the atmosphere are leading to concern worldwide due to their contribution to the greenhouse effect. As the body of evidence supporting the need for change from a carbon rich economy/society becomes stronger, international mitigation agreements require high quality and precise information. Following the Kyoto Protocol and EU agreements to reduce carbon production, countries could utilise default values or comparable international data to calculate their carbon budgets. Initially, approximations were successful for generating a guide to a national carbon stock for reporting GHG inventories to the UNFCCC (Tier 1 ). However, now that the second phase of the Kyoto protocol is running until 2020, greater accuracy is essential and, where possible, nationally specific information is increasingly required (Tier 3, UNFCCC). Forestry and forest soils are seen as a key component in the carbon cycle and depending on their management, can mitigate or contribute to GHG emissions. Litter and soil organic matter (SOM) are two of the major carbon pools required for reporting under LULUCF. In this study, stocks of SOM and litter were recorded along a chronosequence of Sitka spruce (Picea sitchensis (Bong.) Carr.) on wet mineral gley soil. Over a 47-year period, the rate of soil carbon sequestration was found to be 1 .83 t C ha−1 yr−1 . Soil microbial biomass was used to estimate highly active SOM. The mineral soils were also fractionated in a density separation procedure to identify light and heavy SOM pools. These estimates can now be used to model carbon budgets of this most common soil type currently under forestry in Ireland.
    • Tending and thinning of broadleaves: A simple guide to selecting quality trees.

      Short, Ian; COFORD (Select Media Ltd, 2011-11)
      This article describes a simple procedure that can be used to ensure that the correct trees are selected in broadleaf woodland before tending / thinning is carried out, and follows best practice based on the latest Teagasc Forestry research.