The perpetuation of the reigning dominants in climax woodland, and the maintenance of species diversity, are discussed by reference to published work: the importance of the regeneration gap is outlined, and seed production and seedling mortality are investigated as being key factors in the establishment of young trees. Beech masting has been studied by an eight-season record of seed production by individual trees in many places, developing a unique series of objective records for England. There appears to be a basic biennial masting pattern, with a requirement for suitable climatic conditions and the proximity of other beech trees for effective cross-pollination. The effects of defoliation upon the growth of young oaks has been investigated by a controlled experiment on 196 saplings in a plot in Wolverhampton. This has contributed data on a larger population for a longer period than has previously been published. The responses of the trees to light defoliation were not marked but, as the level of defoliation increased, greater numbers of growth zones, more leaves and smaller leaves became apparent, together with impaired relative growth rates and abnormal wood structure. Ramets of cloned oak have been established in a unique outdoor plot. Their synchronous phenology permitted further analysis of defoliation responses, including field measurements of photosynthetic rates. Tree shelter tubes were shown to promote earlier second flushes and to lessen fluctuations in temperature and maintain high humidity. Observations have been made in woodlands, especially in the West Midlands where surveys have established that natural regeneration is taking place, at least in the gaps created by fallen trees. The possibility of encouraging natural regeneration of trees and ground flora on land set aside from agriculture is considered. A synthesis is made of the topics investigated, discussing the origin of the intermittent nature of the phenomena of growth spurts and masting.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:383631 |
| Date | January 1988 |
| Creators | Hilton, G. M. |
| Publisher | University of Wolverhampton |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
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