![]() However, for maximum dwarfing, trees should be pruned when seasonal growth of shoots is almost completed (from late spring to mid summer). Heavy pruning of shade trees usually is done late in the dormant season. Removal of broken, dead, or weak branches has a negligible dwarfing effect on trees irrespective of the time when done. Light prunings can be made at any time of the year. The time to prune depends on the plant species and objectives. ![]() Shade trees are routinely pruned with several objectives in mind, such as eliminating dead, injured, diseased, broken, and crowded branches training for topiary, espalier, or bonsai forms reducing tree size to prevent crowding, avoid street wires, facilitate spraying, and prevent obstruction of views influencing flowering and fruiting invigorating trees and decreasing water loss from the crowns of transplanted trees ( Harris, 1992). Pallardy, in Growth Control in Woody Plants, 1997 Ornamental Trees Nevertheless, it is clear that a diversified food-and-cash-crop livelihood strategy is possible ( Tscharntke et al., 2011). In conclusion, the multifunctional role of shade trees for agriculture and biodiversity conservation is now recognized, but their important role in risk avoidance from insect pest outbreaks is inadequately understood. Removal of shade trees has been found to lower the abundance and richness of birds of most guilds, including insectivorous species ( Philpott and Bichier, 2012) conversely, the abundance of insectivorous birds was greatest when the canopy cover was dense and species-rich, and there was some dead vegetation. In addition, shade trees also provide breeding sites for beneficial insects, such as midges, which are pollinators of cocoa ( Young, 1982, 1983 Young, 1982 Young, 1983). In another study, disease and insect attacks were more prevalent under single species tree canopies than under mixed canopies, supporting the hypothesis that tree diversity minimizes the risks of pest outbreaks ( Bos et al., 2007a,b Bos et al., 2007a Bos et al., 2007b,c). Predation of insect pests by canopy birds is greatest when the canopy is not intensively managed, with the richness of shade trees explaining much of the variation in bird diversity ( van Bael et al., 2007a,b van Bael et al., 2007a van Bael et al., 2007b). Shade has been found to be more beneficial in the dry season and should be reduced by pruning in the wet season ( Staver et al., 2001). Likewise, in coffee plantations, shade trees can be managed to provide optimal light conditions to minimize the risks from pests and maximize conditions for beneficial fauna and microflora, even in areas with different soils and climate. In cocoa, this shade can be controlled to manage the incidence of diseases, such as frosty pod rot, which is caused by the fungus Moniliophthora roreri ( Krauss and Soberanis, 2001 ). Tree shade is important to provide the best growing environment for some crops, especially those originating from the forest understory. Leakey, in Multifunctional Agriculture, 2017 Shade Modification
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