Here are numbers that are helpful when using alfalfa and grass height as an indicator of NDF content. In general:

• Begin cutting 100% grass stands should be cut when nearby alfalfa is 14 inches tall to achieve the desired 50% NDF.
• Begin cutting 50/50 mixed alfalfa and grass stands when nearby alfalfa is 22 inches tall for the desired 44% NDF.
• Begin cutting 100% alfalfa stands when alfalfa is 28 inches tall for the desired 40% NDF.

The desired NDF for all grass fields is 50%, 50/50 mixed alfalfa and grass fields is 44%, and pure alfalfa stands is 40%. Predicted days to cut arebased on daily NDF increases for grasses of 1% point, 50/50 mixed stands of .8% points and alfalfa of .5% point. Typically NDF increases about 0.8 to 1.2/day for grasses expecting the lower end of that range in cooler weather and the higher end in warm. Alfalfa NDF increases about 0.4 to 0.7/day again figuring the lower end of that range with cool temperatures and the higher in warm. Predictions are adjusted for the coming week's weather and right now we are assuming faster than normal growth for the alfalfa.

In the tables in the pdf, locations around the region are listed where we have measured alfalfa height. You can use the location and elevation as a guide to conditions that may be similar to your own. Always check your fields to verify your heights and conditions!

Alfalfa height increased considerably since last week sometimes increasing as much as 10 inches in height. Four eastern and lower elevation fields have been cut. NDF predictions at all locations with 100 percent grass and seventy three percent of the 50/50 mixed indicate they should have been cut by now. With the exception of some higher elevation locations many all grass fields are no longer dairy quality and you should move on to higher quality fields.

This will be our last report for 2018 as we expect a majority of fields to be cut by next Tuesday and the rest by the first weekend in June.

Don't forget to get out a yard stick or tape and check your own fields if your alfalfa is later maturing.