{"id":1037,"date":"2026-06-02T08:36:58","date_gmt":"2026-06-02T08:36:58","guid":{"rendered":"https:\/\/foragebaler.com\/?p=1037"},"modified":"2026-06-02T08:36:58","modified_gmt":"2026-06-02T08:36:58","slug":"sorghum-sudangrass-hay-production-guide","status":"publish","type":"post","link":"https:\/\/foragebaler.com\/pt\/sorghum-sudangrass-hay-production-guide\/","title":{"rendered":"Feno de sorgo-sud\u00e3o: \u00e1cido pr\u00fassico, metabolismo basal e guia de enfardamento"},"content":{"rendered":"
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<\/div>\n
Summer Annual Hay \u2014 Safety and BMR Production<\/span><\/p>\n

Feno de sorgo-sud\u00e3o: \u00e1cido pr\u00fassico, metabolismo basal e guia de enfardamento<\/h1>\n

Sorghum sudangrass produces 4\u20138 tons per acre in one summer season and, in BMR form, delivers digestibility values that dairy nutritionists specifically request. It is also the hay crop with the most serious safety hazard in U.S. production \u2014 prussic acid. This guide covers the safety science producers must know, the BMR vs conventional quality difference, cutting timing, and the baler settings that thick sorghum stems require.<\/p>\n

See Prussic Acid Safety Guide<\/a><\/p>\n<\/div>\n<\/div>\n

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Why Sorghum Sudangrass Hay Is More Complex \u2014 and More Valuable \u2014 Than Most Summer Annuals<\/h2>\n

Sorghum sudangrass (Sorghum bicolor<\/em> \u00d7 S. bicolor<\/em> var. drummondii<\/em>) was developed specifically to combine the high biomass yield of grain sorghum with the fine stems and rapid regrowth of sudangrass. The resulting hybrid occupies a production niche that no other warm-season annual hay crop fills: it establishes in a single growing season, tolerates drought and heat stress that would limit bermudagrass yield, produces 4\u20138 tons per acre across 2\u20133 cuttings, and in BMR form delivers digestibility values competitive with good-quality alfalfa. It demands more from the producer \u2014 in safety management, in baling equipment, and in seasonal timing precision \u2014 than any other hay crop in common production.<\/p>\n

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4\u20138 T\/acre<\/div>\n
Total season yield across 2\u20133 cuttings, surpassing most perennial warm-season grasses in the first production year without the multi-year establishment investment<\/div>\n<\/div>\n
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58\u201372% NDFD<\/div>\n
48-hour neutral detergent fiber digestibility for BMR sorghum sudangrass \u2014 the digestibility metric dairy nutritionists use to optimize milk production per ton of forage consumed<\/div>\n<\/div>\n
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18 polegadas<\/div>\n
Minimum plant height below which sorghum sudangrass hay and grazing carry elevated prussic acid risk \u2014 the single most important safety rule in sorghum forage management<\/div>\n<\/div>\n<\/div>\n
Where sorghum sudangrass hay fits in a production system:<\/strong> It is primarily a supplemental or transitional hay crop rather than a perennial foundation crop. Operations that use it most successfully are those with an established perennial hay base (alfalfa, bermudagrass) who need to bridge a drought or cover a field rotation year, dairy operations that want a high-digestibility summer annual specifically for silage or hay to complement perennial forages, and dryland producers in the southern and central plains where summer annual forages produce more reliably than alfalfa in drought years. It is not a replacement for perennial hay systems \u2014 it is a high-yield, high-risk, high-return single-season tool.<\/div>\n<\/div>\n
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Prussic Acid (HCN): The Safety Science Every Sorghum Hay Producer Must Know<\/h2>\n

\"mowing<\/p>\n

Prussic acid (hydrocyanic acid, HCN) is produced in sorghum species from a plant compound called dhurrin, a cyanogenic glycoside stored in the plant’s vacuoles. Under normal cellular conditions, dhurrin and the enzyme that breaks it down are physically separated. When plant cells are damaged \u2014 by frost, drought stress, wilting, mechanical injury, or even rapid growth \u2014 the vacuole structure breaks down and dhurrin contacts the enzyme, releasing free HCN within the plant tissue. Livestock that consume this material absorb HCN through the rumen wall at rates that can exceed the body’s detoxification capacity, causing cellular asphyxiation within minutes at sufficient dose.<\/p>\n

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\u26a0 HIGH-RISK SITUATION 1: Plants below 18\u201324 inches<\/div>\n

Young sorghum plants have a higher dhurrin concentration per unit of dry matter than mature plants \u2014 specifically, the first 12 inches of growth contain the highest dhurrin levels of any stage in the plant’s lifecycle. The 18-inch minimum height rule is not an arbitrary guideline; it reflects the point at which total plant mass has diluted the dhurrin to a level that poses much lower risk to cattle under normal consumption conditions. Do not cut, graze, or allow livestock to access sorghum sudangrass below 18 inches under any circumstances.<\/p>\n<\/div>\n

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\u26a0 HIGH-RISK SITUATION 2: Post-frost plant and regrowth<\/div>\n

A killing frost is the most dangerous event in sorghum sudangrass management. The cellular damage from freezing temperatures breaks down the vacuole separation of dhurrin and its enzyme throughout the plant simultaneously, producing high HCN levels within hours of the frost event. The risk persists until the plant has completely dried \u2014 typically 5\u20137 days after a hard frost in dry conditions. Do not cut or allow access to frost-killed sorghum material until it is completely dry and brown. Regrowth shoots that emerge from the crown after frost are even higher in dhurrin than the original plant at equivalent height \u2014 the 18-inch rule applies with additional caution to post-frost regrowth.<\/p>\n<\/div>\n

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\u26a0 ELEVATED-RISK SITUATION 3: Drought-stressed plants<\/div>\n

Drought stress concentrates dhurrin in sorghum tissue through two mechanisms: the plant actively increases dhurrin production under stress as a defense response, and water deficit reduces the total plant mass while dhurrin levels remain relatively constant, increasing concentration per unit dry matter. Plants that have experienced significant wilting from heat or drought stress but are above 18 inches may still carry elevated HCN \u2014 particularly if the drought stress was severe and recent. When baling drought-stressed sorghum sudangrass, allow adequate field drying time (minimum 72 hours) before baling to ensure HCN dissipation.<\/p>\n<\/div>\n

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\u2713 WHY PROPERLY CURED HAY IS GENERALLY SAFE<\/div>\n

Prussic acid is volatile \u2014 it evaporates from plant tissue at ambient temperatures during field drying. Research consistently shows that HCN levels in sorghum sudangrass hay drop by 50\u201375% within the first 48 hours of field drying and reach negligible levels (below 500 ppm on a dry matter basis, the threshold generally considered safe for cattle) within 3\u20135 days of field drying under normal conditions. This is why properly cured sorghum sudangrass hay, baled at the correct growth stage above 18 inches and adequately dried, poses minimal HCN risk to cattle \u2014 the HCN has dissipated during the drying process. The risk in hay production is not in the finished bale; it is in the field conditions at cutting and in the adequacy of the drying period.<\/p>\n<\/div>\n<\/div>\n

Important: Horses and sorghum spp. are a different safety category.<\/strong> Horses should never consume sorghum sudangrass hay or pasture in any form. In horses, chronic low-level HCN exposure from sorghum species causes a progressive neurological syndrome called sorghum cystitis ataxia \u2014 bladder dysfunction and posterior incoordination that is irreversible and often fatal. This condition occurs at HCN levels that are below the acute toxicity threshold for cattle and at which cattle exhibit no symptoms. Even well-cured sorghum sudangrass hay is not appropriate for horses, and no amount of field drying eliminates this risk. Keep all sorghum species strictly out of any feeding program that includes horses.<\/div>\n<\/div>\n
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BMR vs Conventional Sorghum Sudangrass: What the Digestibility Numbers Mean in Practice<\/h2>\n

Brown midrib (BMR) sorghum sudangrass varieties carry a genetic mutation that reduces lignin concentration in the vascular tissue by 30\u201350% compared to conventional varieties. This structural change produces the brown coloration in the leaf midrib (the central vein visible on each leaf) that gives the trait its name, and it translates into a measurable improvement in the digestibility of the fiber fraction of the hay \u2014 the fraction that most limits intake and production in cattle fed mature-stage forages.<\/p>\n

\n\n\n\n\n\n\n\n\n\n\n
Quality parameter<\/th>\nConventional SxS at boot<\/th>\nBMR SxS at boot<\/th>\nPractical significance<\/th>\n<\/tr>\n<\/thead>\n
Prote\u00edna bruta (PB)<\/td>\n10\u201315%<\/td>\n10\u201314%<\/td>\nSimilar \u2014 BMR does not significantly affect CP<\/td>\n<\/tr>\n
NDF<\/td>\n58\u201372%<\/td>\n55\u201368%<\/td>\nBMR NDF slightly lower \u2014 less structural fiber per unit DM<\/td>\n<\/tr>\n
48-hr NDFD (fiber digestibility)<\/td>\n44\u201355%<\/td>\n58\u201372%<\/td>\n15\u201320 point improvement \u2014 the primary value of BMR<\/td>\n<\/tr>\n
In vitro total digestibility<\/td>\n58\u201366%<\/td>\n64\u201374%<\/td>\n8\u201310% improvement in total nutrient availability<\/td>\n<\/tr>\n
Yield (tons DM\/acre)<\/td>\n4\u20138<\/td>\n3.5\u20137<\/td>\nBMR may yield 5\u201310% less \u2014 lower lignin reduces stem structural rigidity and stand height<\/td>\n<\/tr>\n
Seed cost premium<\/td>\nBaseline<\/td>\n+$8\u2013$15\/acre<\/td>\nWorth it when marketing to dairies paying NDFD premiums; neutral for commodity cattle hay<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n
The BMR economic calculation:<\/strong> At $180\/ton and 6 tons\/acre conventional yield, gross revenue is $1,080\/acre. BMR at $200\/ton (NDFD premium) and 5.5 tons\/acre yield produces $1,100\/acre \u2014 essentially the same with an additional $12\/acre seed cost, yielding a marginal outcome. If the dairy premium reaches $220\/ton for documented BMR (which some operations achieve with NDFD documentation), BMR at 5.5 tons\/acre produces $1,210\/acre \u2014 a $118\/acre advantage that clearly justifies the seed cost. The economic case for BMR depends entirely on accessing buyers who pay for NDFD \u2014 it does not make sense for commodity beef hay markets where buyers don’t differentiate on digestibility.<\/div>\n<\/div>\n
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Cutting Timing: Managing the Quality-Safety Tradeoff Across the Season<\/h2>\n

Cutting timing in sorghum sudangrass hay production balances three objectives that pull in different directions: quality (peaks early in the growth cycle and declines sharply with maturity), safety (requires minimum height and adequate drying time), and yield (maximizes at later stages). The window where all three objectives are simultaneously satisfied is narrower than most producers expect \u2014 particularly for first-cutting timing where the prussic acid risk is highest.<\/p>\n

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CUTTING TIMING GUIDE \u2014 All cuttings require plant height above 18 inches minimum<\/div>\n
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First cutting (30\u201340 in height)<\/div>\n
Recommended height: 30\u201342 inches.<\/strong> CP 12\u201316%, NDF 58\u201368%. At this height, dhurrin concentration is approaching the safe range and total plant mass provides adequate dilution. Do NOT cut at exactly 18 inches \u2014 the 18-inch minimum is the absolute safety floor, not the target cutting height. Cutting at 30+ inches provides both better quality (more leaf relative to stem) and additional safety margin. Allow 48\u201372 hours of field drying before baling regardless of apparent moisture \u2014 the full drying period is needed for HCN dissipation, not just moisture reduction.<\/div>\n<\/div>\n
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Regrowth cuttings (28\u201335 days)<\/div>\n
Regrowth after the first cutting germinates from crown buds and reaches 30+ inches in 28\u201335 days under good growing conditions. CP often higher in regrowth (14\u201318%) because the regenerating plant has a higher leaf-to-stem ratio in the early growth phase. HCN risk is generally lower in regrowth cuttings than first cuttings at equivalent height \u2014 the plant has already channeled its defensive chemistry investment into the first growth cycle. Standard 30-inch minimum still applies. Do not cut regrowth shorter than the previous cutting’s stubble height (typically 4\u20136 inches) \u2014 leaving adequate stubble protects the crown buds for subsequent regrowth.<\/div>\n<\/div>\n
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Final cutting timing<\/div>\n
Plan the final cutting to allow complete field curing before the first expected frost date. A cutting made 10 days before frost should be baled within 4\u20136 days if possible \u2014 if the bale is not yet field-cured when frost arrives, move it to covered storage rather than allowing it to freeze and re-dry in the field. Frost-killed sorghum hay that has not fully cured carries elevated HCN even after apparent drying. Never cut or bale frost-killed standing sorghum sudangrass \u2014 only bale material that was cut before the frost and has been adequately field-dried before the frost event.<\/div>\n<\/div>\n<\/div>\n<\/div>\n
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Drying Challenges: Thick Stems, Slow Moisture Loss, and Heat Damage Risk<\/h2>\n

\"round<\/p>\n

Sorghum sudangrass at cutting has stems that can reach 3\/4 to 1 inch in diameter at the base \u2014 significantly thicker than alfalfa or grass stems. These thick culms contain a pith center surrounded by a dense vascular ring that holds moisture long after the leaf material has dried. An operator who bales on stem surface moisture or leaf moisture without specifically checking the stem interior will systematically bale hay that appears dry but carries 18\u201322% moisture at the culm core \u2014 hay that will heat severely within the first week of storage.<\/p>\n

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Why conditioning is non-negotiable for sorghum sudangrass<\/div>\n

Unconditioned sorghum sudangrass hay requires 72\u2013120 hours to reach baling moisture under good field conditions, due to the thick stem’s resistance to moisture diffusion. Conditioning that physically crushes the main stem \u2014 using a heavy roller conditioner set at maximum closing force \u2014 splits open the culm and allows direct moisture evaporation from the pith. Properly conditioned sorghum sudangrass reaches baling moisture in 48\u201372 hours. This time reduction is not a convenience improvement \u2014 it is a safety-critical difference because the shorter field time reduces rain exposure windows and allows better integration with weather patterns. Set the mower-conditioner roller pressure at maximum for sorghum sudangrass; settings adequate for alfalfa are insufficient for stems 3\u20135\u00d7 the diameter. PTO shaft specifications for the high conditioning drive loads are in Especifica\u00e7\u00f5es dos componentes da caixa de engrenagens e da transmiss\u00e3o da tomada de for\u00e7a (TDF) para uso agr\u00edcola<\/a>.<\/p>\n<\/div>\n

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Measuring stem moisture, not just surface moisture<\/div>\n

Use a long-probe insertion meter (18\u201324 inch probe) to measure the windrow core. For sorghum sudangrass specifically, push the probe through the windrow until it contacts the base of a cut stem \u2014 the stem-bottom region is the last part of the plant to dry and is the most critical measurement point. Any reading above 18% at the stem base indicates the hay is not ready to bale safely. Wait for the stem core reading to drop to 16% or below before baling \u2014 at that point the outer leaf material and upper stem will be well within the 12\u201314% range and the overall bale moisture average will be appropriately low.<\/p>\n<\/div>\n<\/div>\n

Do ted sorghum sudangrass \u2014 it is one of the few crops where tedding is consistently recommended:<\/strong> Sorghum sudangrass cut with a disc mower forms a dense, slow-drying mat due to the thick stems stacking compactly on the ground. Tedding within 2\u20134 hours of cutting, while the stems are still flexible and green, lifts and aerates this mat and reduces drying time by 30\u201350% compared to unmanaged windrows. Unlike fine-stemmed teff or bermudagrass (where tedding risks shatter), sorghum sudangrass at high moisture is too flexible to shatter \u2014 ted as vigorously as needed to fully open the windrow and allow air circulation.<\/div>\n<\/div>\n
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Baler Settings for Thick-Stemmed Sorghum Sudangrass<\/h2>\n

\"agricultural<\/p>\n

Sorghum sudangrass is the most mechanically demanding hay crop to bale. Its thick, rigid culms require more force to compress into a bale than any other material commonly handled in round baler production, and the coarse stems tend to bridge across the pickup and chamber in ways that fine-stemmed crops do not. Operators who bale sorghum sudangrass without adjusting from their alfalfa settings typically experience excessive PTO torque spikes, frequent pickup plugging, and bales with a loose interior surrounded by a compressed shell rather than uniformly dense material.<\/p>\n

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BALER ADJUSTMENT GUIDE \u2014 Sorghum Sudangrass vs Standard Alfalfa Settings<\/div>\n
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Density spring tension<\/div>\n
Increase 15\u201325% above alfalfa settings.<\/strong> Sorghum sudangrass culms have 2\u20134\u00d7 the cross-sectional area of alfalfa stems and resist compression proportionally. Standard alfalfa spring tension produces sorghum sudangrass bales that are structurally weak \u2014 the stems have not been compressed enough to interlock \u2014 and the bales lose shape within days of storage. Higher spring tension also reduces the bridging problem because the crop material is drawn into the chamber more forcefully at each tine contact.<\/div>\n<\/div>\n
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Velocidade em rela\u00e7\u00e3o ao solo<\/div>\n
2\u20133.5 mph maximum<\/strong> in sorghum sudangrass windrows. This is half to two-thirds the speed appropriate for alfalfa. The thick stems require more time per foot of windrow to be fed into and compressed within the chamber without jamming. At higher speeds, the pickup cannot clear each batch of stems before the next arrives, producing the characteristic “load-pause-thud” that precedes a pickup jam. Use a tractor with adequate PTO power reserve \u2014 the baler may demand 60\u201375% of the tractor’s maximum PTO output during peak compression events in dense sorghum windrows.<\/div>\n<\/div>\n
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Bale size selection<\/div>\n
4\u00d75 or 5\u00d75 minimum; avoid 4\u00d74.<\/strong> A 4\u00d74 bale of sorghum sudangrass has insufficient internal volume for the thick stems to orient and interlock \u2014 the bale tends to form with a center void surrounded by a shell of compressed material rather than uniform density throughout. Larger chamber volumes allow the stems more room to align and compress. At 5\u00d75 with adequate density spring tension, sorghum sudangrass produces a mechanically stable bale that handles normally in storage. The relationship between bale size, density setting, and the structural integrity of bales from different crops is in the guia de densidade de fardos redondos e qualidade da ra\u00e7\u00e3o<\/a>.<\/div>\n<\/div>\n
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Pre-cutting knife system<\/div>\n
Engage if equipped \u2014 significant jam reduction.<\/strong> Pre-cutting knives that chop the incoming sorghum stems into shorter sections dramatically reduce the bridging events that cause pickup jams in full-length sorghum. A 30-inch sorghum stem fed whole into a bale chamber can orient perpendicular to the bale circumference and create a structural bridge that stops chamber rotation. Pre-cut to 6\u201312 inch sections eliminates this failure mode entirely. Sorghum sudangrass is the crop most likely to justify adding a pre-cutting knife system to an existing baler if not already equipped.<\/div>\n<\/div>\n
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Net wrap requirement<\/div>\n
Net wrap is required.<\/strong> Sorghum sudangrass bales wrapped with twine lose their cylindrical shape within 1\u20132 weeks of storage as the rigid stems push against the twine at contact points. Net wrap maintains continuous restraint that allows the stems to settle into a stable configuration without progressive distortion. For round baler models with integrated net wrap systems and high-torque chamber drive configurations suited to sorghum sudangrass baling, browse our modelos de enfardadeiras redondas<\/a>.<\/div>\n<\/div>\n<\/div>\n<\/div>\n
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Quality Testing: What the Forage Test Reveals Beyond the Basic Numbers<\/h2>\n

Sorghum sudangrass hay has quality characteristics that a basic ADF\/NDF\/CP forage test under-represents \u2014 and one quality characteristic that matters profoundly to dairy buyers that most basic tests do not include. Knowing which test panel to order and how to interpret the results is the difference between marketing sorghum sudangrass hay at commodity prices and documenting its true feeding value to buyers who pay for it.<\/p>\n

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Standard forage panel (minimum)<\/div>\n