Tree surgery operations have to be scheduled with regard to the season and with due care to the legal protection afforded to nesting birds and bats.
Complete tree removal can be carried out at anytime of year, only it may not be possible due to nesting birds or the presence of bats. This is particularly so for densley growing species, such as conifers and trees with lots of ivy, and old trees with nest holes.
Overall Reductions should not be carried out in early spring, just before bud burst and during flowering, or in early autumn, just before leaf fall. At these times the trees are in a growth process that renders them particularly weak to pruning. Reductions can be carried out during the winter or ideally summer, when the tree is in full growth and is better able to respond to wounding.
Crown thinning can be carried out at anytime of year, although it is better to avoid early spring, just before bud burst and during flowering, or in early autumn, just before leaf fall, particularly if it is a relatively heavy crown thin.
Hedges - Hedge pruning and hedge reductions are frequently put on hold during the bird nesting season, in particular leylandii and laurel hedge reductions. Wild birds are legally protected and they love dense hedges. Wild bird nests are almost impossible to detect prior to work. For this reason it is better to schedule hedge pruning work outside nesting season.
Pollarding is traditionally carried out in the winter months, as long as it is not left too late. Pollarding in early spring when the buds are starting to swell, or after the leaves have started to appear, is particularly detrimental to the trees health.
Coppicing, like pollarding, is also traditionally carried out in the winter months, as long as it is not left too late. Pollarding in early spring when the buds are starting to swell, or after the leaves have started to appear, is particularly detrimental to the trees health.
Prunus Species - Trees of the Rosaceae family, particularly the genus Prunus, are very susceptible to a widespread and common fungal disease known as Silver leaf (Chondrostereum purpureum). The fungal spores enter through wounds including pruning cuts. Once established (in Prunus) it proves to be almost always fatal. The time of year that pruning is carried out is a very important factor preventing this disease and dramatically reduces the risk. They should be pruned in the summer (usually between June and August) when there is little risk of infection.
The genus Prunus includes plum, cherry, damson, gage, peach, apricot & almond
Weather does also have an effect on what can take place. During heavy periods of wet weather on clay soils, the soil can become compacted in areas around retained trees. Where possible tree work should be rescheduled until conditions improve. Also for health and safety reasons it could be dangerous to climb beech trees in very cold winter weather as the branches can be brittle.