Distance markers

[jfrain2004]

Is there any standard rules for distance markers or are they laid out at the pleasure of the local green keeper?
Are markers on the course usually to the front of the green unless stated on the card and more importantly as I never see it stipulated on a course card, are distances as given on a tee box ALWAYS to the centre of a green?

[Big_M]

sprinkler heads and colored stakes usually indicate distance to the center of the green. I don't think there's any standard rules, but most courses use the red (100), white (150), blue (200) approach. Most courses also have sprinkler heads giving distances to center.

[Brooklyn]

An odd thing I've noticed is that at the country club my folks belong to its near impossible to find a yardage marker(well besides the 150 stakes) and the city course down the street from my house has it labeled on all the sprinklers.