On Aug. 18, Ken from Chenango County emailed me, seeking my advice for the following scenario: “We usually harvest two cuttings of sorghum, in July and August. This year, being dry and then wet all summer, our sorghum and Japanese millet didn’t do as well. We have about six acres of sorghum and three acres of Japanese millet that are finally ready to cut. However, I’m not sure if we will get a second crop in September if we cut now. Do you have any thoughts on whether it is best to let it grow or wait a few weeks and then cut it? We would like to no-till triticale into the sorghum and millet stubble in mid-September.”
Ken and his parents own and operate a grass-fed organic dairy farm. This means that all their forages must be harvested before they set seed and start resembling grains. This is fairly critical with perennials, which just yield higher quality in immature plants. It’s mandatory (according to the National Organic Program (NOP) for grass-fed livestock) for hot climate summer annual (HCSA) crops that form distinct heads like corn, sorghum, sudangrass (and their hybrids) and millet. NOP also mandates that grass-fed organic people avoid seed head formation in winter forages, such as wheat, cereal rye, triticale, speltz and barley. HCSAs harvested with few or no seed heads generally have time to make second cuttings, frost permitting.
I called Ken back on Aug. 21 to find more information about the stands in question. I learned the sorghum and millet were on parcels planted to the same crops in 2022. Prior to last year, both parcels had lain fallow for five years. They had also received decent amounts of liquid manure, compliments of their dairy cattle during 2022 and 2023 – but not during the fallow years. He told me that the sorghum and millet were both about 3.5 to 4 feet tall throughout the majority of the two fields, except for spots where vegetation was shorter and yellower. In those problem areas he said that the soils were shale-heavy and not so deep. Most of the fields are Lordstown and/or Mardin soil type – typical upland materials.
Ken’s family had pretty well charted their cropping course away from corn silage even before converting their dairy to grass-fed. Here are some of the reasons they give for abandoning corn entirely: First, with any shifting weather patterns, not putting all your eggs in one basket (or one crop) could give you a much more stable forage supply. One of those alternative crops is the often-ignored brown mid-rib (BMR) forage sorghum or sorghum-Sudan. It is planted when the soil is warmer than 60º F (preferably 65º) and the forecast is for warmer conditions. This can conveniently take place after most if not all the first cut hay crop is harvested. Taking first cutting followed by sorghum is one way to increase the yield from a runout hayfield.
Second, in the event that they want to plant grain corn as a cash crop, there’s a little-known bonus trait: corn can follow sorghum with no rootworm issues, because the sorghum root’s prussic acid kills the larvae, then the adults look elsewhere to lay the eggs for the next generation. Drilled sorghum in narrow rows protects the soil from erosion and raindrop impact a month or more earlier than corn. In moisture-short conditions – which have been a serious problem at many Northeast locations this year – sorghum will yield 50% – 100% more digestible dry matter than corn on the same water (per University of Texas research).
Additionally, a rapidly growing consideration is that sorghum does not get corn tar spot. It has its own tar spot different from corn, but sorghum agronomists have not seen it in the U.S. For many growers with corn fields devastated last year by tar spot, switching to sorghum was a logical move this year.
Third, although they are growing BMR sorghum this year, they are willing to consider older-style non-BMR sorghum, considering it the premier, economical forage for raising dairy replacements and dry cows. They reason that higher energy corn silage is problematic since its starch contributes to fat deposition rather than body size. The highly digestible BMR sorghum will do the same. Non-BMR forage sorghum species will fill the animal to maximize rumen development and function without getting the animals over-conditioned.
Non-BMR sorghums yield higher than the BMR versions. Many farmers report they are growing better, large-framed replacement animals when they switched from corn and BMR sorghum to non-BMR sorghum as the preferred forage.
Fourth, here’s their reason for planting some Japanese millet: This crop is more forgiving than sorghum and/or sudangrass grown in less-than-ideal soil fertility. A field that tests pH of 5.7, low in phosphorus and is marginally drained will support millet much better than it will the other HCSAs listed above. Though called Japanese, this millet mostly developed in India on subsistence farms, where the main form of plant nutrition was water buffalo manure.
I gave Ken the following recommendations for winter forage seeding rates: 100 lbs./acre of Gainer 154 triticale, 8 lbs./acre of Clifford red clover and 3 lbs./acre of Tetrax meadow fescue. The triticale seed should be placed 1.25 inches down, drilled. If the seed has to be spun on, increase seeding rate by 20% – 25% for all three crops. The red clover should be pre-inoculated. Individual seed dealers may make acceptable substitutions for these varieties.
Once the winter forage is up, fertilizer – based on soil test results – can be top-dressed. Triticale can tolerate total nitrogen of 70 lbs./acre, including manure and granular sources, over winter without threat of lodging.
Folks who are not grass-fed organic dairy farmers should allow their HCSAs to form seed heads, up till the point where vertical whole plant growth has stopped. Past that point the plants divert energy toward fiber formation, away from net energy for lactation.