The colonisation of freshly sawn Corsican pine lumber by sapstain and mould fungi was investigated at a sawmill in Hampshire, UK. Three repeat trials encompassing the different seasons of the year were carried out over two years. Results show that fungal colonisation of sawn lumber is dependent on the effect of time of year. Sawlogs were stored for different intervals up to 16 weeks before conversion to boards. Boards were then stored for up to 12 weeks after milling and sampled every 4 weeks to determine the effect of timber ageing on fungal colonisation up to 28 weeks after felling. The metabolic activity of wood cells over the period after felling of the original tree was also measured. It was evident that the defacement of boards reached maximum levels after 12 weeks exposure irrespective of seasonal influences. Initial levels of fungal growth on lumber were reduced if the boards were milled from logs stored for a period prior to conversion. Investigations into the metabolic activity of the wood cells revealed significant levels of respiration taking place up to 28 weeks after felling of the original tree including 12 weeks post-conversion into boards. Boards were used to make a nested stack arrangement allowing plastic tanks top be placed in the centre. The tanks contained a sub-sample of the full-size boards in order to investigate insect activity and effects of gammairradiation. A total of 115 insect species representing 16 of the 34 British orders were collected during the trials. Seventy-two percent of these insects were collected from within the stacks of lumber and investigations using sealed tanks containing boards showed that the insects could influence the fungal colonisation of sawn lumber. Despite the relatively short length of the trials, a succession of insect colonisation from fungivores through to predators and detritivores was recorded. Boards, which were sterilised by gamma-irradiation, were preferentially colonised by mould fungi and subsequent internal staining was confined to the outer surface. Trials with short-length billets allowed the wood-colonising ability of selected sapstain fungi to be investigated under controlled conditions following sterilisation by gamma-irradiation or autoclaving, and storage at 30°C and 20°C. Lesion formation in gamma-irradiated tissue was solely due to the fungus potentially conditioning the wood for colonisation. Colonisation studies also revealed that different fungi exhibit different strategies enabling them to infect timber. Pathogenic species demonstrated a relatively fast initial growth rate to establish themselves before triggering any host anti-fungal responses in the wood. The characteristic lesions created in the billets were investigated using light and electron microscopy to reveal hyphal invasion and or/ wood cell modifications. Respiratory activity of the lesions was elucidated using radioactively labelled glucose allowing the metabolic pathways to be ascertained and demonstrated that wood tissue in the apparently healthy regions adjacent to the lesions reacted as if infected. Future work considers the possibility of biocontrol, using insects in combination with gamma-irradiation of sawn lumber and also further investigations into the reaction zones produced by the fungus growing in the wood.

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Η εργασία αυτή αποτελεί μελέτη του δάσους της Στροφιλιάς (Αχαϊας) με σκοπό την εξαγωγή συμπερασμάτων για τη δυνατότητα, τους τρόπους και τη χρησιμότητα της τεχνητής αναδάσωσης. Επίσης, διερευνώνται οι αλλαγές που είναι πιθανόν να προκαλέσει μια εκτεταμένη αναδάσωση στο οικοσύστημα. Παράλληλα θα αναφερθούν οι παράγοντες που υποβαθμίζουν το οικοσύστημα, οι κίνδυνοι που αντιμετωπίζει και με πιο τρόπο οι αναδασώσεις μπορούν να ωφελήσουν την περιοχή, αλλά και οι πιθανές δυσμενείς επιπτώσεις από λανθασμένες αναδασωτικές πρακτικές. Για το λόγο αυτό γίνεται αναφορά τόσο στις θεωρητικές αρχές που διέπουν τις αναδασώσεις όσο και στον τεχνικό τρόπο που αυτές οι αρχές θα εφαρμοστούν στην πράξη, προσαρμοζόμενες στις ιδιαιτερότητες της περιοχής. / This work constitutes study of forest of [Strofilias] of (Achaia) aiming at the export of conclusions on the possibility, the ways and the usefulness of artificial reforestation. Also, are investigated the changes that it is likely to cause a extensive reforestation in the ecosystem. At the same time will be reported the factors that downgrade the ecosystem, the dangers that faces also with more way the reforestations can profit the region, but also the likely unfavourable repercussions from erroneous [anadasotikes] practices. For this reason it is mentioned the theoretical aspects that condition the reforestations andin the technical way that these conditions will be applied into practice, adapted in the particularities of region.

Terminal Report submitted to Regional Forester, U.S. Forest Service, Ogden, Utah / In accordance with a cooperative agreement between the Forest Service and the Laboratory of Tree-Ring Research at University of Arizona for a joint inventory and dendrochronological study of bristlecone pine. / In the Administrative Study Plan, as set forth 10 August 1966 and approved 16 August 1966, it was proposed that a joint inventory and dendrochronological study of bristlecone pine, Pinus aristata Engelm., be conducted by the Forest Service and the University of Arizona on the Snake, Mt. Moriah, Ward Mountain, and the Schell Creek divisions of the Humboldt National Forest in Nevada. Through a closely integrated inventory and dendrochronological program designed to take full advantage of the unique scientific resources available at the University of Arizona, the proposed study was expected to yield maximum information on the age, volume, growth, extent, and area of bristlecone pine and to provide authoritative data for interpretive and future planning uses. Dr. J. O. Klemmedson of the Department of Watershed Management, for the inventory phase, and Dr. C. W. Ferguson of the Laboratory of Tree -Ring Research, for the dendrochronological phase, were co- investigators of the project.

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