Where our ranch is located, Lincoln County in Eastern Washington State, we get a first cutting (the first crop taken off a field in any given year), a second cutting (the second crop taken off that same field in that given year), and possibly a third cutting (the third crop taken off that same field in that given year), provided Mother Nature complies and gives us enough sunshine, dry days, and warm nights.
Mother Nature is, however, very unpredictable! When harvesting hay, you learn to make hay while the sun shines, as the old saying goes!
The first growth off of a field for the year is the "first cutting". Many people erroneously feel that first cutting hay is not to be considered as good feed. We tend to disagree, provided it is of good quality and was cut when relatively immature (pre-bloom stage), before the plant is allowed to mature to the point where the stem becomes larger and coarser. This is when the lignin (an indigestible part of the fiber component associated with cellulose and hemicellulose in the cell wall) content has become sufficiently high so as to make the hay more unpalatable and indigestible and the nutritive value has declined greatly. This can happen with 1st, 2nd, or any cutting of hay if left growing too long.
In our area of Eastern Washington, depending upon the temperatures of the days and nights, it typically takes 40-45 days for regrowth of alfalfa, 40-45 days for mix hay, 40-45 days for Orchardgrass, and 55-60 days for Timothy. This is termed the "second cutting" which usually has a larger percentage of leaves to stems, has a finer and softer stem, has increased percentages of crude protein and crude fat, and has a lower crude fiber percentage (depending upon the stage of maturity at which it was cut). More nonstructural carbohydrates (starches and sugars) and protein are in the leaves than in the stems. These starches and sugars are very digestible, therefore making the hay higher quality.
If the growing season is long enough on any given year, it may be possible to secure a third cutting. In regions that lie south of our location, the growing season is longer and hotter, making alfalfa the prime hay crop, and often as many as four or five cuttings may be taken from a single field.
Third cutting is typically very soft hay that is primarily leaves with very few small stems. While beautiful to look at, it can be "rich" (higher in nutrients, more digestible, and having a higher intake potential) and can be very low in crude fiber. It is our opinion that third cutting hay is often too high in nutrients and does not contain sufficient fiber content to be the only hay in the diet of many animals. It can, however, be used in conjunction with a higher fiber, good quality, relatively immature 1st or 2nd cutting hay, and creates greater variety and interest in the chewing experience. We suggest that you feed the different hays at different meals so as to eliminate waste.