First Cutting Updates – Utilizing Alfalfa Heights as a Predictor for Quality

The SCNY team is monitoring alfalfa heights again this spring to help predict quality and %NDF for first cutting hay crop.  Alfalfa height has been proven to be a reliable indicator of NDF values in the field for alfalfa, alfalfa/grass mixed and all grass stands.  Results will be compiled and emailed on a weekly basis – please feel free to forward on.  To be included on the weekly email, or to be removed from the email, please contact Betsy Hicks, bjh246@cornell.edu.

UPDATES FOR THE WEEK OF MAY 22nd, 2017:

Mowing for all hay stands is well underway across the region.  Some farms took advantage of the bit of nice weather and have finished up their first crop for their milking herd.
Points for the last week:
•    Growth of alfalfa across the region reached anywhere from over 3” to almost 10” where there was ample sunlight and minimal rain/cloud activity.
•    A weather event late last weekend that included hail damaged some alfalfa stands north and east of Cortland – fields were harvested soon after.
•    In alfalfa, everything is either early bud or mid bud stage.  The breaking point for mid-bud is about 30”.
•    There are some fields in the southern portion of our region that are dealing with alfalfa weevil and fields have been damaged.
•    Heavy grass fields that have some alfalfa mixed with them seem to have alfalfa that is struggling.  Orchard grass especially in mixed fields was towering over alfalfa.
Weather forecast looks like rain Thursday/Friday and Sunday/Monday.  Slight chances of rain for next week every day (20%) but I’m sure there will be hay weather to be had.

Thoughts on pure grass fields that are past peak quality:  If you are able to segregate your first cutting, you may want to leave your fields that are past peak quality and save them for dry cow or heifer feed and focus on getting your mixed fields in at peak quality.  Certainly, field conditions will play a role, but yield can be a factor to take into account as well.

Please let us know conditions you observe while harvesting, and any comments back about the alfalfa height project are appreciated!  We also welcome any sample results you would like to share, so forward them on me, bjh246@cornell.edu.  You can also post harvest pictures on our team’s Facebook page – https://www.facebook.com/SCNYDairyandFieldCropsTeam/ and use the hashtag #harvest2017.

Thank you, and stay safe!
Betsy

Additional Information:

The numbers that are indicators for using alfalfa heights for NDF content are as follows:
•    100% grass stands should be cut when nearby alfalfa is 14 inches tall, to achieve 50% NDF
•    50/50 mixed alfalfa/grass stands should be cut when nearby alfalfa is 22 inches tall, to achieve 44% NDF
•    100% alfalfa stands should be cut when alfalfa is 28 inches tall, to achieve 40% NDF

Predicted days to cut are based on daily NDF increases for grasses of 1.0% point, 50/50 mixed alfalfa/grass stands of 0.8% points, and alfalfa of 0.5% points and are adjusted for the coming week’s weather.  Typically NDF increases about 0.8 to 1.2 per day for grasses, with cooler weather being the lower end of the range and warmer weather being the higher end.  For alfalfa, NDF increases about 0.4 to 0.7 per day, also dependent upon warm/cool weather.

The weekly email for the month of May will have a table of the locations around the region where we have measured the alfalfa height, as well as the elevation.  Even if your fields aren’t measured, you can use the location and elevation as a guide to conditions that may be similar to your own.  We now cover six counties throughout South Central NY, including Tioga, Chemung, Broome, Tompkins, Cortland and Onondaga.  Other teams and associations throughout the state are also measuring fields.  For more information, contact that county’s association to find out if fields are being measured there.

Betsy J Hicks
Area Dairy Specialist
South Central New York Dairy & Field Crops Team
Cornell Cooperative Extension
60 Central Ave
Room 140
Cortland, NY 13045
518.428.2064 cell
607.391.2673 office
607.391.2680 fax
bjh246@cornell.edu
http://scnydfc.cce.cornell.edu/
https://www.facebook.com/SCNYDairyandFieldCropsTeam/