How often should you grease a tractor for light duty?

[Reddogs]

Or I'd say the closest estimate of that usage.
Some zerks would be more critical, like the front axle pivot.
In winter I mainly plow and blow so my front axle pivot is the only one that works hard so I do it often.
FEL simply idles.

I am the opposite, my FEL does most of the work and I seldom use the PTO or BackHoe.