| | What is yellowfeed?
Yellowfeed is when an annual cereal crop is sprayed with glyphosate at the milk to soft dough stage and allowed to stand until dry. Once dry, it can be cut and baled, and used for forage. Because the plant continues to grow for a period after glyphosate is sprayed, it is important to spray prior to the desired stage, so that the plant will have stopped growing by the time the desired stage is reached.
What are the advantages of yellowfeed?
Because yellowfeed is left standing to dry, rather than laying in windrows, it greatly reduces weathering losses and windrow turning if a rainfall event occurs. The crop should dry faster as air movement is greater through a standing crop rather than windrows. Spraying the crop with glyphosate also provides a means to control perennial weeds. Perhaps the greatest advantage is that it allows for harvesting to be scheduled, since the plant will be held in a suspended state once the glyphosate takes effect.
How long do I have to let the crop stand before it is dry?
When there is little to no rain after the crop has been sprayed, generally the crops were dry enough to be cut and baled after 12-15 days, and generally showed little yield loss up to 30 days after spraying except under very wet conditions. When the weather was wet for an extended period after spraying, the time required for drying was much longer, and in some cases, the crops were still not dry enough for baling after 38 days from spraying.
What is yield and quality of yellowfeed?
Generally, a slight yield increase of about 10-15% occurred after the application of glyphosate. This occurs because the crop continues to grow for a period after the spraying event. If and when yield reductions occurred, it was usually observed after day 15.
Consistently the protein of oat and barley crops declined until 8-22 days post glyphosate application, after which protein then leveled off. This decline in protein ranged from 0.9 to 3.3 percentage points.
The response of total digestible nutrients (TDN) was variable. During dry harvest conditions, TDN either remained constant or increased slightly. However, when wet harvest conditions occurred, TDN either remained constant or decreased.
Reports from producers indicate that the palatability of yellowfeed is good, and is equal or greater to that of regular greenfeed.
Are there differences between crops?
Barley appears to dry about 4-7 days sooner than oats. Barley stands well after spraying, but if left standing after it is dry, the heads curl to the ground, which may cause some losses to quality and yield. Oats tends to lay over, but still stands at a height of 12-18 inches, which will not interfere with cutting. Kernels and leaves of both crops stay attached, even when the crop is left standing 7-10 days after it is dry.
What are some problems associated with yellowfeed?
Currently the spraying of annual crops for yellowfeed is a non-registered use of glyphosate. A high clearance sprayer is required for glyphosate application. Also, there is the added cost of applying glyphosate, and there will be no crop regrowth that could otherwise be used for fall grazing. Yellowfeed must be swathed, as crimping would cause some of the heads and leaves to be lost. Wet harvest conditions may make drying of yellowfeed difficult, and cause losses in yield and quality.
Yellowfeed Trial 2001-2003 (if you google this, the document from Sask Ag should come up to link to)
Yellow-Foragebeef.ca (if you go to Foragebeef.ca, there will be a folder titled Yellowfeed, nestled under the Forage side, in the Hay section. Please click on this folder and link to it)
Prepared by Ag-Info Centre, Alberta Agriculture & Forestry
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