Sarah E. Lyonsa, Quirine M. Ketteringsa, Greg Godwina, Jerome H. Cherneyb, Karl J. Czymmeka,c, and Tom Kilcera,d
a Nutrient Management Spear Program, Department of Animal Science, Cornell University, Ithaca, NY, b Soil and Crop Sciences Section of the School of Integrative Plant Science, Cornell University, Ithaca, NY, c PRODAIRY, Department of Animal Science, Cornell University, Ithaca, NY, and d Advanced Agricultural Systems, LLC, Kinderhook, NY
Including a cool-season crop like triticale in a forage rotation can be a rewarding enterprise for dairy farms in the Northeast. Double cropping with winter cereals can provide environmental advantages such as reduced risk of erosion and nutrient loss, enhanced soil fertility, and improved rotation diversity, in addition to increased total season yields. Planting before September 20th was shown to increase nitrogen (N) uptake and biomass in the fall (see Lyons et al., 2017), but the impact of fall management on spring performance was unclear. To evaluate the effect of planting date and fall N availability on triticale forage yield and quality, three trials were conducted from 2012-2014.
The three trials were planted with triticale (King’s Agri-Seeds Trical 815 variety) from late August to early October on research farms in eastern NY (Valatie) and central NY (Varna). None of the fields had a recent manure history. Each trial had two planting dates (one before and one after September 20). Triticale was planted at a 1-inch seeding depth and 7.5-inch row spacing (120 lbs/acre seeding rate). To create a range in soil nitrate availability, 5 N rates were applied at planting in the fall (0, 30, 60, 90, and 120 lbs N/acre; main plots). Biomass was sampled in the fall (see Lyons et al., 2017). In the following spring, the same 5 N rates were applied at dormancy break (0, 30, 60, 90, and 120) for each fall N rate (sub plots). All plots were harvested at flag leaf stage in May of each year (from May 14-21) at a 4-inch cutting height. Measurements included dry matter yield, crude protein (CP), the most economic rate of N (MERN), the ratio of fall biomass to spring yield at the MERN to see if fall biomass can predict spring yield, and “Nitrogen Use Efficiency” (NUE). The NUE is the measure of N taken up in relation to yield, and is calculated by subtracting the yield when no N was applied in the spring from the yield when N was applied (at 30, 60, 90, or 120 lbs N/acre), and dividing that value by the N rate applied: NUE (lbs DM/lbs N) = (Triticale yieldN rate – Triticale yield0 N)/N rate. A higher NUE means that more of the N that was applied was taken up by the triticale.
We found that when no N was applied in the spring, N applied at planting the previous fall increased spring yield only when triticale was planted by September 20 (Figure 1a). Across all trials, yields with no fall or spring N applications averaged 0.8 tons DM/acre. With fall N applications ranging from 30-120 lbs/acre (no spring N), yields ranged from 1.4 to 1.9 tons DM/acre. Yields trended upward with increasing fall N rates, but the only significant yield response to N was at the 30 lbs N/acre treatment. Where triticale was planted after September 20, fall N did not significantly increase spring yield (1.2 tons DM/acre average) (Figure 1b). Crude protein at spring harvest followed a similar trend as yield, but it took a fall application of 120 lbs N/acre to see a significant difference in CP (9.4 versus 10.7%) in the spring (no N applied at green-up) and that occurred with early planting only. Because fall uptake of N does not seem to greatly influence forage protein content in the spring, these results suggest that proper spring fertilization management for optimal nutritive performance is most important.
Figure 1: Effect of fall N application on triticale yield and crude protein concentrations in the spring. Triticale was seeded on two planting dates: before September 20 (A), and after September 20 (B). No N was applied at green-up in the spring N. Data are averages for three locations.
Although fall N application and planting date had some impact on spring yield, neither treatment affected spring MERN (Figure 2a), yield at the MERN (Figure 2b), or NUE at the MERN (17.6 lbs DM/lbs N average). Additionally, the ratio between fall biomass and spring yield was not impacted by the treatments. The earlier planted sites had higher ratios (closer to 1) because with earlier planting there was more fall biomass and the relative gain in yield in the spring was smaller.
Figure 2: Spring most economic rate of N (MERN, A) and yield at the MERN (B) for different fall N fertilizer rates and planting dates of triticale.
Conclusions and Implications
Winter cereals like triticale grown for forage in double crop rotations can provide environmental benefits and additional harvestable forage for dairy producers in the Northeast. When no N was applied in the spring, a small fall N application at planting (30 lbs N/acre) increased yields in the spring if the stand had been planted before September 20. There was no benefit of fall N when the stand was planted later in the fall. Crude protein was only increased when a large amount of fall N (120 lbs N/acre) was applied at a planting date before September 20 and when no spring N had been applied. The MERN and yield at the MERN for each trial were not influenced by fall N or planting date, suggesting that spring N management is by far the most important management consideration for achieving optimum yields. A larger sample size than just three locations may be needed to detect any differences but this research suggests that on fields without recent manure histories, triticale forage requires 60-90 lbs N/acre at dormancy break to achieve optimum yields. Work is ongoing to determine N needs for forage winter cereals under a variety of management scenarios, including manured fields.
This work was supported by Federal Formula Funds, and grants from the Northern New York Agricultural Development Program (NNYADP), New York Farm Viability Institute (NYFVI), and Northeast Sustainable Agriculture Research and Education (NESARE). For questions about these results, contact Quirine M. Ketterings at 607-255-3061 or email@example.com, and/or visit the Cornell Nutrient Management Spear Program website at: http://nmsp.cals.cornell.edu/.