With 16th century logistics, staying in the field for extended periods of time probably requires extensive foraging / raiding. There is an old adage about an army traveling on it's stomach....
Consider this: if it takes 1 lb of food (ignore calories for now) to feed 1 soldier for one day, then feeding 50 soldiers for 20 days is 1000 lbs of food and water. (This is probably a bit light, but it depends on how much water you need to carry, and water is heavy)
In 20 days, soldiers can probably travel 10 miles a day (possibly more, but lets assume no roads but not terribly rough terrain). How are you going to get the 200 lbs of food the 200 miles you have gone? Horses and wagons, probably. But you now have to feed two horses and the teamster for 20 days. Their food has weight, too. Perhaps they eat a collective 5 lbs of food a day (teamster 1, horses 2 each), so they need to carry an additional 100 lbs of food. Just being in the field for 20 days (not very long), and you have to carry 10% more food just to feed the people carrying food!
This isn't taking into account other things like medicine, special equipment, replacement weapons / ammunition, tools, tents, etc. And the further you go, the more you need to carry with you. The more you carry, the more your teamsters and horses eat. And that's just the start of it...
A 16th century army would have cooks, medics, smiths (blacksmiths, gunsmiths, armorsmiths), navigators, engineers (bridges, forts, siege warfare), teamsters, cart wrights, animal handlers, special troops (archers / gunners, pikemen, cavalry, rangers / scouts), artillery, etc. That doesn't even start to consider non-official army personnel, like prostitutes, soldiers family members, and the king's favorite court jester.
Recruiting and supporting and army is a very costly affair. Modern logistics planners have a number they call the 'teeth to tail' ratio. It measures the number of people in an army that actually go out and fight, versus the number of support personnel. It will be pretty low, perhaps 1:10 for ancient armies, to 1:100 or more for advanced modern armies. (Technology takes a lot of support)
I bet you can find estimates of 'teeth to tail' for all sorts of fighting forces through the centuries if you google that phrase.
For your example, if we use my estimates, the troops alone consume 50000 lb a day, and the cavalry horses another 33000 lb of food and water. Your teamsters are going to have their hands full (and their bellies empty) keeping your army in the field for a year.