Harvesting
Deciding When to Cut
For optimum quality legume hay, cut around every 28 days or when one out of ten plants has a bloom. This is generally when the plants are at their peak nutritionally and the stems tend to be softer and more palatable. If the crop is left standing past this point, the protein in the leaves start to be used to produce lignin which is what gives the stem of the plant strength. Hay that is cut at a more mature stage will look more like sticks or twigs in a bale and will be more of a brown color. Alfalfa is known for its high protein content, so letting it grow past the optimum maturity level is like letting good food go to waste. However, some animals do not need the amount of protein that is provided from a diet of perfect, leafy, 1/10 bloom alfalfa. In this instance, growers will allow their crop to continue to grow and mature. This allows more hay volume per cutting.
The optimum feed value in most grass crops is determined by how mature the boot or head of the plant is. For example Timothy should be harvested in the mid to late boot stage. This is the point where the head has begun to mature and small green buds have been formed inside the sheath of the head. At this point the plant has not matured enough to begin to lose moisture and become brown.
Evaluating Hay Quality- From the University of Maryland
| Alfalfa | 1st cutting: Bud stage. (Green buds where flowers will form.) Subsequent cuttings should be cut at 1/10 bloom. If cutting a new spring seeding, allow the crop to reach full bloom before cutting |
| Clovers | Cut at early bloom to 1/2 bloom. |
| Bermuda Grass | 10-15 inch height for the first cutting, and then again every four weeks. |
| Wheat, Ryegrass, Oats, Barley and Timothy | Boot to early head stage. Green buds inside sheath of head. |
| Sudangrass, Sourghum Hybrids, Pearl Millet, and Johnsongrass | Cut when the crop gets to a height of 40 inches or early boot stage, whichever comes first. |
Figure 1. Effect of plant maturity on forage intake and digestability.
Source: Adapted from Blaser, R.,R.C. Hammes, Jr., J.P. Fontenot, H.T.Bryant, C.E. Polan, D.D. Wolf, F. S. McClaugherty, R.G. Klein and J.S. Moore. 1986. Forage-animal management systems. Viginia Polytechnic Institute, Bulletin 86-7.
