Forage Sorghum Seed

Treat it as high risk and keep stock off for now. Frosted, wilted or drought-stunted sorghum, and the fast regrowth that follows a drought-breaking rain, carry the highest prussic acid (cyanide) levels. Even a low prussic acid variety like Bounty needs this caution. If you're unsure, get a feed test before grazing. When stock do go back in, make sure they're full rather than hungry, offer sulphur licks or blocks (sulphur helps the liver detoxify cyanide), and watch them closely for the first hour.

Signs come on fast, often within 15 to 20 minutes of eating toxic sorghum: rapid or laboured breathing, frothing, bright red gums, muscle tremors, staggering and convulsions. Badly affected animals can die very quickly. Cattle are more susceptible than sheep. Move all stock off the crop immediately and quietly, and call your vet straight away; vets can treat poisoning with an intravenous antidote if they reach the animal in time. Then work out the trigger, usually stressed regrowth, frost or hungry stock.

Don't count on it. Hay made from a sorghum crop that is unsafe to graze stays hazardous, because haymaking doesn't reliably remove prussic acid, and nitrate concentrated in the stems carries straight into the bale. Ensiling helps more: about three weeks in silage roughly halves the cyanide, but it still needs testing before feeding. For quality hay or silage from a crop like Bounty, cut a healthy, unstressed crop and get a feed test whenever the season has been tough.

We recommend 10 to 20 kg/ha for Bounty Forage Sorghum, sown into moist soil once it reaches 16°C and rising. As a general rule, sit toward the top of the range where moisture is reliable or under irrigation, and lower in drier dryland situations. Bounty suits heavy soils with 350 mm or more of rainfall and a soil pH (CaCl2) of 5.0 or above. The seed comes coated and treated with Gaucho and Thiram to help protect seedlings through establishment.

The most common cause is sowing into soil that's still too cold. Sorghum needs soil at 16°C and rising, with around 18°C ideal; in cooler soil it germinates slowly and seedlings sit exposed to disease and insects for longer. Other culprits are a dry or cloddy seedbed, ground that waterlogs, as sorghum doesn't tolerate waterlogging, and residues from Group B herbicides, which many summer crops can't handle and which can carry plant-backs of up to 18 months. Check your spray history before sowing.

Start grazing earlier and harder. With Bounty, begin grazing when plants reach 1 to 1.5 metres; leave it longer and stock leave the coarse stems behind. Strip or rotationally graze so each break is eaten evenly, then slash any remaining stalks to promote even, leafy regrowth. Don't graze or slash below 15 cm if you want good regrowth, and give the crop time to recover between grazings. Managed this way, you can expect four or more grazings under ideal conditions.

No, we don't recommend it; forage sorghums are not considered suitable for horses. Horses that graze sorghum, Sudan grass or sorghum x Sudan grass hybrids over time can develop sorghum cystitis ataxia, a nerve disorder causing hind-leg incoordination and urine dribbling, and the damage can be permanent. Bounty is a sorghum x Sudan grass hybrid, so keep sorghum paddocks for cattle and sheep, managed for prussic acid. Talk to your vet if horses may have had access.

Yes, heavy soils are where forage sorghum does best, because they hold more water. Bounty Forage Sorghum is suited to heavy soils and has tolerance of low pH; it needs a soil pH (CaCl2) of at least 5.0 and 350 mm or more of rainfall. Avoid parts of the paddock that sit wet, as sorghum doesn't tolerate waterlogging. If your country is sandier, Shirohie Millet can be sown on lighter soils than forage sorghum, given good nutrition.

It can. Sorghum readily accumulates nitrate, and heavy nitrogen combined with stress such as drought, frost or cloudy weather lets nitrate build up, mostly in the stems. High nitrogen on low-phosphorus soil also raises the prussic acid risk. Apply nitrogen in moderate amounts after grazings rather than one big dose, keep phosphorus up, and get a feed test if the crop is stressed. Forage above 1.5% nitrate (as potassium nitrate, dry matter basis) is considered potentially dangerous.

It can, because a summer crop uses stored soil water that a fallow would otherwise carry into winter. DPIRD modelling for the south coast found wheat after a summer crop such as sorghum yielded 200 to 400 kg/ha less. Weigh that against the value of the feed. To limit the cost, sow only where there's good stored moisture or reliable summer rain, keep weeds controlled so moisture isn't wasted, and finish grazing and terminate the crop well before the break so the profile can refill.