Crop Comments: Dry conditions point to sorghum

This morning (Tuesday) Frank, one of my crop program advisees, called to tell me that he had finished first cutting. This Central New York farmer crops about 150 acres of mixed mostly grass hay baleage; most of that land is rented. He raises a few beef cattle, and works some off-farm at a machinery dealership. He said the hay just harvested appears to be very high quality, but that the quantity was down, compared to last year. In 2017, because of the almost non-stop rainfall in June, most haymakers in the Northeast produced plenty of first cutting baleage. Quantity wasn’t the problem… quality, however, was. During 2017’s first cutting, making decent small square bales for most growers was extremely challenging. This year I’m seeing a lot more first cutting square bales coming off the meadows.
Frank told me that this year’s first cutting dried down very rapidly to baleage moisture: standing hay swathed one morning was ready to be round-baled the following morning, once the dew was off. Two days back-to-back with mostly clear skies and temperatures peaking in the upper 70s is what made that possible. But another factor that enhanced dry down was lower ground moisture. I’ve noticed that most fields where I take soil samples the soil doesn’t really stick too well to the flighting on the augur. I have to pull the probe out of the ground very carefully. When I have taken the samples… prior to meticulously screening them… I let them air-dry on newspaper, a process which doesn’t take very long now.
With hay drying conditions being better than average… and significantly better than 12 months ago… I asked Frank if he would consider planting a crop that doesn’t need more moisture, namely sorghum, Sudangrass, their hybrids, or possibly millet, preferably Japanese. I asked him if he would consider growing a sorghum-Sudangrass hybrid, and/or some Japanese millet. I told him that if there are some meadows where the second cutting appears to come on in a less than robust fashion… due to moisture lack… he should consider planting one of these moisture miser summer annuals just mentioned. I had earlier explained to Frank the benefits these summer annuals as more than just emergency crops.
But I’m going to review them for our readers. Sorghum, particularly the BMR (brown midrib) varieties, has been shown by reputable peer-reviewed research to support milk production equally as well as good quality corn silage.
The ability of BMR sorghum (and Sudangrass) to support milk production as well as corn silage is particularly important for several reasons. First, as more and more folks have begun making baleage with their perennial feeds, being able to harvest an annual “energy” crop with the same equipment has increased appeal to folks whose corn chopper is on its last wheels. Secondly, sorghum (along with millet and Sudangrasses) does a pretty good job of suppressing weeds… unless the soil fertility is terrible. This means no need for herbicides nor row cultivator weed control.
Thirdly, sorghum, Sudangrass, and millets have fibrous root systems. This means they stop degrading soil organic matter, a claim that corn and soybeans cannot boast. Fourthly, when the heavenly spigots slow down to a trickle (or stop entirely), sorghum, Sudangrass, and millets need half as much water to produce a pound of forage dry matter as does corn. And fifthly, dairy folks whose farms are certified grass-fed organic are very fortunate to have these three crops to choose from as a prime forage energy source. In fact the pioneer grass-fed organic milk marketer in the Northeast has the motto: “No Corn, No Grain, Just Grass”.
These five points made up my sales pitch to Frank. Then I told him that I had another crop program advisee who was very land-challenged, and wanted someone to grow him a hundred bales of organic sorghum-Sudangrass baleage. Frank’s reply was: “I’m in. Get the seed lined up.” I cautioned Frank that these crops need to have soil warm up to 60 degrees Fahrenheit demanded by this hot climate summer annual. I also always point out that sorghum originated in sub-Saharan Africa, where moisture is very lacking during the early part of the growing season. Average annual rainfall in that part of Africa is only nine inches.
This super-arid background for sorghum, Sudangrass, their hybrids, and millets brings up a sixth factor: all four of these plant types are C-4s. C-4 means that its carbon building blocks are crafted with four carbon modules. Without getting too technical, this means that the ability of the plant to retain moisture… as regulated by stomates (openings on leaf surfaces)… is much more efficient than is the case for non-C-4 plants. The C-4 class boasts such members as these just cited, plus sugarcane, and the amaranth family (particularly the nuisance Palmer’s amaranth).
Wondering about the apparent lack of moisture that many Northeast areas are experiencing, I called my neighbor one township away, who is a well-trained seasoned weather observer. She said that April’s precipitation totaled 3.1 inches, while May’s was 3.36 inches (both somewhat lower than normal), and that the first 10 days of June were running a little in the red rain-wise. A lot of brooks are running pretty low already; some are even dry.
Just a few points in closing. Be sure soil potassium levels are adequate. That element regulates the opening and closing mechanism of stomates on leaf surfaces; properly performing stomates maximize moisture retention. Try to round-bale both perennial forages and hot climate summer annuals with moisture levels around 30 percent. For this the wrapping job must really be good. By my observation, lower moisture baleage (and haylage for that matter) tend to produce lower protein solubilities. And when soil fertility is lacking (such as pH being uncomfortably below 6.0), millet will outperform sorghum.

Leave A Comment