"Nick Maclaren" suggested:

...remove them and plant a more manageable hedge.
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Consider Bamboo. OK, so there are a few that are not well behaved, giving
the rest a bad name. The ones that *are* well behaved make ideal plants for
boundary hedges or screens. Buy young non invasive plants as larger plants
can be expensive. Fargesia robusta or Phyllostachys nigra, the Black Bamboo,
are two of the best. P. nigra is usually compact and takes a year or so
before the stems turn black. However, the end result is worth waiting for.

MikeCT