To mow or not to mow (annually)? Great question! You're right to hold off mowing until fall to avoid disturbing nesting birds. Based on this it sounds like you value birds and other wildlife so my advice is to divide your field into quarters and establish even longer rotational mowing intervals like 5 years or more. This will allow shrub and sapling growth to establish. This type of habitat is also known as young forest and it can be incredibly rare in our landscapes and very valuable to all sorts of wildlife. Here's a link to a blog I wrote about young forest - Old Fields, Young Woods. There's also a great website called Youngforest.org with information about how to establish and maintain young forest. We also recently had a MyWoodlot forum thread that discusses brush hogging so you may find that interesting too. I could go on and on about young forests so let me know if you have more questions!

You've made a couple of good points here: Leaving vegetation up over the winter: This provides winter habitat for many species of wildlife. The dead stalks of field vegetation serve as nesting cavities for pollinators including bees and wasps. And maybe not surprisingly, this vegetation also captures garbage that tends to get blown around during the winter and often enters waterways. So leaving it up, and then doing a spring trash pickup can be a good combination. Rotation Length: I like rotations. Pavlesich made the case for it in his post, and I agree with his points. Another factor here is cost. If you do not own the equipment, then it does cost more to have an increased number of visits to mow increasingly smaller field sections.