Well, pigs eat. Pigs manure. Pigs sleep a lot. Pigs drink and wallow. The best thing pigs do is dig.
This is a post about digging. Pigs dig for fun and to find food. This week we put them in the pasture near the iron pile where they discovered a small pile of odd parts that had been buried in the pasture over time. These are probably things my grandpa dropped out there 20 or more years ago.
Here’s a view of the whole pasture they left. They did more digging further away, less closer and almost none up close.
Looking the other direction I have drawn some lines. The further line is where the fence was. The near line is where they stopped digging. Why did they stop digging?
They did not dig where they manured because pigs are clean animals. They manured near the fence and did not dig in their manure. There is almost no manure anywhere else in the pasture. Just there by the fence.
The pasture will recover quickly where the manure is. The pasture will recover slowly where they dug but, in the long term, the massive disturbance will allow opportunity for plant succession that would not have happened otherwise. There is a seed bank in the soil that will now have a chance to come to life. There will be grass. There will be weeds. It will be great.
When keeping pigs on pasture it is important to leave them enough room to play, to dig, and to take care of business. If you place too many pigs in too small of a space or leave them in one place for too long, the whole area will be defoliated. We try to manage things so when the pigs run out of fresh grass to eat they are moved to a new location. By that measure the pasture has a reasonable chance to recover quickly.
Good luck with your own experiments with pigs, grass and portable fence. Things may work out differently for you.
Chism Heritage Farm 
We have four pigs about three months old. They are still in a pen for now. They poop in the corner only. The two males will pee all around, but the females will only pee in the corner.
You should put some pictures of your pigs on your blog. They are a major remodeling tool and fun at 3 months. Are you using an electric fence? Are you moving them or are you using them for more extensive renovation? What are you using for a shelter?
Right now they are in a pen in the barn. We built them a little house for shelter. We are working on refencing a section of our woods. It will be divided in four sections about a half acre each. We plan to rotate them from paddock to paddock every month or so. We hope/think they will turn the floor of the woods and help make compost when in their pen in the winter and/or early spring, if we decide to keep them over the winter. They’ve already made about six inches of the stuff in their pen between turning the dirt with the sawdust we’ve been adding each day.
Joel Salatin uses nylon rope to hang electric fence from trees in his forest pig pastures. That might be a useful shortcut if your spring is busy. Also, his pigs don’t return to the same soil for a full year.
We are also Salatin fans so were familiar with what you are describing. In double checking with the head farmer here, aka, my husband, we will actually have 8 paddocks so it should get them through the year. We have more woods to use in the future. We are just getting started so I’m sure we will learn as we go. I will post on the pigs soon and be sure to add some pictures.
Pigs also roll in mud for something,Because that’s their job