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Once in a while it may become necessary to cut hack bushes 

 severely — to within a foot of the ground if need be — in order to 

 achieve a desired purpose. For example, if a specimen has greatly 

 exceeded the limits of height assigned to it, heavy pruning will 

 bring it to earth; and similar treatment is accorded those hushes 

 which have become scrawny, lopsided, or weakened by insect or 

 fungus attacks. It must he recognized, however, that such severe 

 cutting- hack inevitably results in the loss of a crop of blooms for 

 one year; and, by stimulating excessive vegetative growth, may so 

 upset the plant's balance that no flowers are produced for two or 

 even three years. For these reasons a wise pruning program aims 

 to avoid the necessity for drastic cuts by giving the bushes annual 

 attention. 



Light pruning to promote symmetry can be done as soon as the 

 flowers begin to fade and will do little to decrease flower production 

 the following year. Cutting the flowering branches with long stems 

 for interior decoration is a "killing-two-birds-with-one-stone" proc- 

 ess in that it also is an effective means of preventing a too rapid 

 increase in height. 



We are told that when the flower-clusters have faded they should 

 be cut off to prevent seeds from forming and thus conserve the 

 plant's energies. It can easily be seen that the practice is worth 

 while in the interests of tidiness and good looks, but it is doubtful 

 whether it is an important conservation measure. 



Varieties vary greatly in the number of suckers produced; with 

 some it is a constant battle to keep them from forming a thicket 

 around the base of the bush. They may be cut off at: any con- 

 venient time, but it is well to leave a few as an insurance against 

 the loss of the bush should the presence of borers in the main stems 

 go unnoticed until irreparable damage has been done. 



Once in a while, say every two or three years, or whenever it 

 seems desirable, one or more decrepit branches should be cut off 

 close to the ground to allow strong suckers to take their place and 

 thus rejuvenate the bush. 



Propagation 



Lilacs may be increased by seeds, cuttings, suckers, layers, and 

 bv budding and grafting. 



