through and through before composting them. When I have a ton or two
of spoiled hay bales around, I spread them out on the ground in a
single layer and leave them in the rain for an entire winter. Doing
this sprouts most of the grass seed within the bales, thoroughly
moistens the hay, and initiates decomposition. Next summer I pick up
this material, remove the baling twine, and mix it into compost
piles with plenty of more nitrogenous stuff.

One last word about grass and how it works when green manuring. If a
thick stand of grasses is tilled in during spring before seed
formation begins, its high nitrogen content encourages rapid
decomposition. Material containing 2 percent nitrogen and lacking a
lot of tough fiber can be totally rotted and out of the way in two
weeks, leaving the soil ready to plant. This variation on green
manuring works like a charm.

However, if unsettled weather conditions prevent tillage until seed
formation has begun, the grasses will contain much less nitrogen and
will have developed a higher content of resistant lignins. If the
soil does not become dry and large reserves of nitrogen are already
waiting in the soil to balance the high C/N of mature grass, it may
take only a month to decompose But there will be so much
decomposition going on for the first few weeks that even seed
germination is inhibited. Having to wait an unexpected month or six
weeks after wet weather prevented forming an early seed bed may
delay sowing for so long that the season is missed for the entire
year. Obstacles like this must be kept in mind when considering
using green manuring as a soil-building technique. Cutting the grass
close to the soil line and composting the vegetation off the field
eliminates this problem.