Hay Cutting

Hay cutting takes a standing crop of grass or other forage, cuts it, and dries it in the field until it will store. What comes off feeds stock through a season when nothing grows, or goes onto beds as mulch, or into a compost heap as the dry carbon-rich material a heap needs. Nothing about the work is hard to do; everything is hard to time.

Forage is at its best for a short window as it comes into flower, and quality falls from there while bulk keeps rising. Cutting ten days late can cost around 20 percent of the digestible nutrients and 40 percent of the protein. The cut crop then has to dry where it lies, and every pass of a rake or baler shatters leaf, the most valuable part of the plant, costing 10 to 25 percent. Moisture at stacking is the hard line. Above roughly 22 percent in small bales, or 18 percent in large round ones, a stack can heat itself to 54 to 60 degrees C (130 to 140 F) and catch fire, so a marginal stack is probed daily for two or three weeks. Cutting grass does not take a fire risk off a site; it concentrates it.

Keeping the hay dry afterwards repays more than any improvement to the cut: left outside it loses 15 percent or more of its value to weather, under cover under 5 percent in a year. The practice moves fertility rather than making it. Every tonne carried off takes about 25 kg of nitrogen, 21 kg of potash and 6.5 kg of phosphate with it (50, 42 and 13 lb per ton), so ground that is only ever cut thins out unless something is returned to it. Hay brought in from elsewhere carries its own risk: some broadleaf weedkillers stay active in hay, manure and compost for three or four years, composting does not break them down, and tomatoes, peppers and beans grown in it come up twisted or not at all. Sowing a few peas in a pot of it first is the check. The same timing and moisture limits hold for a scythe over a few beds as for a mower over fields.