The reason why the shoot tips are stuck together is that there are tiny little grubs inside the ball of leaves that have stuck them together to protect themselves from birds such as blue tits and also wasps who spend most of their year searching out caterpillars and grubs to feed to their young.
As the majority of Maple cultivars are grafted plants, simply because it is the only way to guarantee the consistency of the type, there will always be the potential for the understock of the graft to sprout forth and try and take over.
When a previously healthy Maple suddenly collapses into death, dieback or sheds its leaves at an unnatural time of year the probable cause is the obnoxious Vine Weevil.
These insects are quite large at 1/2 inch or so long black and are the classic weevil shape of a rounded body and a long snout and feelers.
