I recall discussing with the Course Chairman at Boat of Garten (Scottish Highland course) the maintenance challenges. They have a mixture of silver birch, heather and birch, plus longer grasses to contend with.
As I recall, if the silver birch is not 'managed' then the heather is lost. And, they prefer heather to silver birch. And, they are on a small acreage so genuine out of play areas are less common. Consequently, they also have gorse removal programs. A lot of Boat of Garten's maintenance was dedicated to maintaing that 'ideal maintenance meld' balance of heather, silver birch and gorse.
I also understand that The Old Course has implemented a 10 year cutting cycle on their gorse, aimed at 'peaking' at the times of Open Championships but also ensuring the ingress of gorse into playing lines is managed.
Perhaps Gorse is Scotland's equivalent of Augusta's azaleas - it looks fantastic behind greens and generally outside the area of play. Royal Melbourne doesn't have gorse, but it has some high grass areas (out of play generally) where you wouldn't want to go, and you wouldn't want to have your ball found!
James B