I'm going to apologize right now. Sorry for writing a post that only three or four of you dear readers will truly enjoy. But since my face lights up when the conversation shifts to grazing and winter feed budgeting, I'm going for it.
The ne plus ultra of being a grazier (one who manages grazing animals) is to take a herd through an entire calendar year on pasture alone, with the animals doing 100% of the work of harvesting. Accomplishing this feat is easier said than done, particularly in my climate. Everyone I know feeds hay through the winter, some less than others, but everyone does it. The metric we graziers use is "days on hay" because it approximates "money out of pocket". Winter feed is the single largest expense when it comes to keeping cows. Every day not feeding hay means more money in my pocket.
In many parts of the mid-west and plains there are producers who routinely carry their herds through with only a few days of hay feeding, or none at all. In the upper mid-west (like the Dakotas, and Canadian prairie provinces) there is an intermediate practice called "swath grazing" where a field is mowed into windrows, and these swaths are then left in the field. With portable electric fence the swaths can be doled out for the cattle to eat in the field. Even in a deep snow year the cows will learn to dig to the swath for dinner and the thick layer of grass makes their effort pay off. If the grass is spread evenly over the whole field the return on investment for digging effort is much lower for the hungry animal. The benefits to the farmer accrue in his or her pocketbook because swathing a field is much less expensive than taking it several steps further into finished bales.
Nobody I know swath grazes because it is so much wetter here (avg precip is 45 inches vs +/- 20 for much of North Dakota). The swaths would need to be cut in October and the risk is high that of most of the feed value in the cut grass would leach out before solid freezes stop the degradation process.
Some grasses maintain reasonably good feed value as long as they're still attached to their roots and the snow doesn't make them inaccessible to grazers. But I get a lot of snow, and it is routine for the conditions here to make grazing a losing proposition for a cow. One of the gurus of year-round grazing, Jim Gerrish, literally wrote the book on it. He cut his chops in Missouri, and has since emigrated to Idaho. In his book he says the Great Lakes states and the Northeast are the two most difficult parts of North America to graze year-round. The freeze-thaw cycles and regular deep snows play havoc with forage quality and livestocks' ability to get at it in those two bioregions. I suppose the Pacific Northwest climate presents major diffculties to the would be year-round grazier too. The constant wet for 2/3 of the year without much, if any, solid freezing makes for soft ground. Heavy hoofed animals will damage swards of grass if they spend much time on soggy spots. If the whole farm is sodden for more than half the year, that is a real challenge. The 'normal' solution is to make hay and haul it to the animals for the part of the year when pasture is unavailable, no matter the reason.
I don't have an answer for constant mud, but a possible, and I want to emphasize possible, solution to the snow problem is a forage that will stand up tall and retain some feed value. Several years ago while brainstorming on the topic of winter grazing Garth thought of bamboo. It's a grass. It's routinely fed to animals all over the place in Asia. Panda bears, which by all accounts are horrible at digesting roughage, survive on it through snow filled winters. Genius that Garth is, he was not the first American to consider bamboo as a possible crop. There are not a lot of academic papers on it circulating the web, but there are a few. Most of the interesting papers I dug up were pretty dated - like from the 1950s - which in some respects encouraged me further because the move to Management intensive Grazing by beef producers really only got legs in the 1980s. It seems likely that nobody has gotten around to trying bamboo as a stockpiled forage because of the challenges I'll now enummerate -
1. Establishment costs for bamboo groves are very high. Purchasing enough rhizomes to plant an acre of ground could easily cost thousands of dollars (Seed for pasture/hay mixes is an order of magnitude less).
2. Insufficient research on the feed value of standing bamboo is available to make informed decisions.
3. Non-existant information about how best to manage livestock to harvest bamboo.
4. Unknown whether a stand of bamboo will tolerate yearly defoliation and still remain the dominant plant in a given area (this is probably location and climate dependent).
5. Unknown how much hoof traffic a bamboo grove will tolerate before culms are damaged and the stand suffers (this is probably type of bamboo, time of year, size of animal, and type of soil dependent).
6. Unknown possible yield of forage/acre (this is location and bamboo species dependent).
7. Unknown fertility requirements (type, amount, and timing of fertilizer application to optimize quality and yield).
That many 'unknowns' means there is a lot of room for experimentation and also a lot of room for 'failure' of concept. Any one of the unknowns I listed could derail the project, at least under my climate and soil conditions. Failure here would not necessarily mean bamboo is worthless everywhere. It might be a great forage to stockpile in Missouri or Arkansas as a drought buffer since their milder winters allow more than one year's worth of leaves to accumulate. Standing forage yield per acre could potentially be quite high...
But I live in New York and dream of grazing my cattle during February, even if I can't actually make it all the way to May 1st when the regular pasture species are tall enough to graze. I purchased four types of cold hardy bamboo, but only one has truly thrived - Phyllostachus bissetii. I also dug three unidentified types in Pennsylvania and two of them have done pretty well. I have not pampered my plantings because I wanted to see how well they'd tolerate competing with the grasses and forbs that dominate my land "naturally". Now that I'm satisfied the bamboo is capable of holding its own against other plants I've decided to give it a helping hand with some mulch and fertilizer. The mulch is apparent in the leading photo. This will accelerate the growth of my bamboo grove and allow me to test the bullet points I listed above. I also plan to propagate the thriving types more widely. Otherwise it spreads only by runners and makes it about 6 ft per year.