Pruning

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In microeconomics, pruning taken as a metaphor from gardening, refers to the removal of "excess" items from a budget.

Pruning (Algorithm) is a term in mathematics and informatics which describes a method of simplification of a decision tree.

An example of very bad pruning on some birches, with removal of most of the crown, resulting in a high probability of decay and early death of the trees

In gardening, pruning is the practice of removing diseased, overmature, or otherwise unwanted portions from a woody plant. Pinching back herbaceous plants, such as chrysanthemums to encourage denser growth or more profuse or delayed flowering, is a form of pruning. So, on an even smaller scale, is the garden practice of "deadheading", or removing spent flowers before they begin to set seed, in order to concentrate a plant's energy on continued flower production.

Correct pruning of a branch. First cut a notch on the underside at cut '1', then remove the bulk of the weight of the branch with a cut at '2'. This stops the weight of the branch tearing the bark if done with just one cut. Then locate the branch collar, a strip of rough bark running down from the topside of the branch at its junction with the stem. Cut '3' should start just outside this, and angle outwards such that angle 'a' is equal to angle 'b', leaving a slight stub, wider at the bottom than the top.

Pruning small branches can be done at any time of year. Large branches, with more than 5-10% of the plant's crown, can be pruned either during dormancy in winter, or in mid summer just after flowering, for species where winter frost can harm a recently-pruned plant. Autumn should be avoided, as the spores of disease and decay fungi are abundant at this time of year.

Some woody plants that tend to bleed profusely from cuts, such as maples, or which callous over slowly, such as magnolias, are better pruned in summer or at the onset of dormancy instead. Woody plants that flower early in the season, on spurs that form on wood that has matured the year before, such as apples, should be pruned right after flowering, as later pruning will sacrifice flowers the following season.

Pruning: dense growth after shearing

Shearing to form hedges or topiary is also a form of pruning, in which most of the growing points are tipped back, to produce artificially dense growth. Proponents of pruning, both gardeners and orchardists, often argue that it is an art, and that it improves the health of the plant and makes sturdier structure, often referred to as the "scaffold"; opponents believe that pruning harms plants' "natural" forms.

Pruning

See also