– Jason Hartschuh, OSU Extension AgNR Educator, Crawford County (originally published in Progressive Forage Grower)
Photo 1: Timeliness is impossible if it rains when harvest should happen!
Winter annual forages have become a mainstay for many dairy and beef rations across in the country. Winter annuals have increased farm profitability by serving not only as double crop forage with corn silage, soybeans, or corn grain but also a cover crop that helps to trap nitrogen and protect soils from heavy winter and spring rainfall. The greatest challenge for many of my local producers is managing harvest timing to maximize quality with spring rain fall events that not only delay custom harvesters but also cause your perfectly timed harvest to come to a halt. Such as in 2020 when our plots in Photo 1 spent a week in standing water when we should have been harvesting triticale and wheat for the highest quality. To harvest at least some of your summer annuals at the highest quality possible two strategies of diversification can be applied either planting on multiple dates or using multiple species.
Photo 2: Four species at optimal harvest time.
Figure 1: Growth Stage in Cereals
Diversifying to multiple species is one of the best risk management practices. Planted on the same day the four species we have been comparing flowered over a 3 week period. These trials were conducted at the Ohio Agricultural Research and Development stations in Fremont and Jackson Ohio. Allowing us to capture two very different growing conditions each year. Photo 2 shows four species with cereal rye ready for it first harvest on the right side. The four species we are comparing are cereal rye, triticale, barley, and wheat for yield and quality at an ideal harvest timing of Feeks 10, head in the boot to delayed at Feeks 10.5, flowering. Figure 1 shows the growth stages of small grains. By utilizing species as our risk management strategy we are still able to plant as soon as soils are fit after the hessian fly free date instead of delaying planting arbitrarily as a harvest management strategy for 3 weeks with rain delays turning this into a 6 week delay. Planting delays have been shown to sacrifice tillering and yield.
Figure 2
We have found not only differences in speed of maturity but also in tonnage between species at the same maturity. On average most species put on a half a ton more dry matter as they mature to Feeks 10.5 but triticale added over a ton of dry matter, figure 2 shows average dry matter yields. Cereal rye and triticale had a similar yield of around a 1.25 tons average but had a low of .75 ton to over 3 tons per acre. The lowest yielding location had lower tillers experiencing excessive winter and spring rain fall. At Feekes 10.5 triticale takes the lead in tonnage with an average of 2.75 tons and a high of 5 tons.
Figure 3
While tonnage is critical another important part of the risk management decision is how quality declines as the species matures, shown in figure 3. All species saw a similar decline in crude protein of about 2 percent with no significant difference in crude protein percentage between species, only between harvest dates. Neutral Detergent Fiber, NDF and Total Digestible Nutrients, TDN were a different story. These two nutrients moved inverse of each with TDN declining and NDF increasing between the two harvest timings, both of which leads to a decline in quality. TDN which is one measure of energy was the highest for wheat at both harvest timings. Harvesting at Feeks 10 had the highest TDN with all species declining when harvest was delayed to Feeks 10.5. Barley had the least quality decline or all species. Wheat stands out as having the greatest digestibility. This is followed by triticale and cereal rye at Feeks 10 with NDF increasing about 10 points as both matured. One other major factor that lowers forage quality is the amount of last years crop residue you harvest with the forage. This problem occurs most often when cereal grain forage is planted after corn grain harvest. Another challenge we have had is with winter survivability of barley, loosing our northern stand in 2020. Being sure to select varieties for your winter climate is critical to success.
Photo 3: Fall manure or nitrogen application show benefit
While species selection is beneficial for risk management so is nitrogen management which can affect yield and quality. For our trials we have been applying 20 pounds of fall nitrogen to improve tillering followed by an additional 50 pound of nitrogen at Feeks 6, with green up. These rates are based on work done at Cornell University which found that the most economical nitrogen rate was about 70 pounds per acre. There was a huge range though in the most economical nitrogen rate from 0-120 pounds per acre. This large variation in nitrogen need was shown to be from the fields manure history and soil drainage. Poorly drained fields needed more nitrogen than the well-drained fields with the same manure application history. Liquid manure can be an important part of cereal grain forage management. We have seen liquid manure used after planting to improve germination and tillering. Photo 3 shows the benefit off fall manure or nitrogen application with the areas on the right edge of the field where no manure was applied in the fall being much smaller compared to where manure was applied which is a thicker crop and darker green.
Utilizing multiple species of winter annual small grains allows you to harvest high quality forage even when the weather doesn’t cooperate. This allows you to harvest high quality forage at Feeks 10 to feed lactating animals and slightly lower quality forage at Feeks 10.5 for animals only needing maintenance nutrition. Cereal rye and triticale were the highest yielding, but barley and wheat maintained their quality better when harvest was delayed. When using multiple species always plan to harvest them at prime quality and then except them at lower quality when the weather forces a delayed harvest.