# The Effect of Meat and Bone Meal on Yield and Herbage Quality in Silage Maize
## 3 Results and Discussion  
### Maize Yield  
Maize yields were affected by fertilization and weather conditions during three growing seasons (2014, 2019, and 2020) (Table 3). Whole-crop maize yields (DM = 300 g\(\cdot\)kg\({}^{-1}\) fresh matter (FM) ranged from 50.9 Mg\(\cdot\)ha\({}^{-1}\) in the treatment without fertilization (zero-fert) to 75.6 Mg\(\cdot\)ha\({}^{-1}\) in the 1.0 Mg\(\cdot\)ha\({}^{-1}\) MBM treatment. Green herbage yields were significantly higher in fertilized treatments than in the zero-fert. No significant differences in maize yields were found between MBM treatments vs. the NPK treatment or between MBM treatments. Maize yields peaked in response to the lowest MBM dose (1.0 Mg), which supplied 45 kg P. In this treatment, apart from P and N contained in MBM, 79 kg N (50% of the total N rate of 158 kg) was supplied by mineral fertilizer. In the inorganic NPK treatment, where N and P were contained only in mineral fertilizers (158 kg N and 45 kg P), the quantity of harvested herbage was 2.9 Mg lower than in the treatment with the lowest MBM dose. In treatments No. 3 and 4, mineral N was applied (79 and 40 kg, respectively) to widen the narrow N:P ratio in MBM, based on the results of a previous experiment where 1.5 Mg\(\cdot\)ha\({}^{-1}\) MBM (approx. 120 kg N) was insufficient to fully meet the N requirements of silage maize [24]. In maize grown for grain, the yield-forming effect of MBM applied at 1.5 Mg\(\cdot\)ha\({}^{-1}\) every year [13] or at 3.0 Mg\(\cdot\)ha\({}^{-1}\) every two years [27] was comparable with that of mineral fertilizers. A beneficial influence of MBM on the yield and quality of maize grown for grain has been described by numerous authors [9; 13; 15; 23; 24; 26; 27; 28]. It should be noted that lower doses of MBM did not fully cover the N demand of high-yielding crops, whereas higher doses led to excessive accumulation of plant-available P in the soil [11; 13; 23; 27; 32; 33; 34]. In the present study, the mineral N added to MBM had no significant effect on silage maize yields, contrary to expectations. \begin{table}
\begin{tabular}{c c c c c c c c} \hline \multirow{2}{*}{**Month**} & \multicolumn{5}{c}{**Average Air Temperature (\({}^{\circ}\)C)**} & \multicolumn{5}{c}{**Total Rainfall (mm)**} \\ \cline{2-7}  & **2014** & **2019** & **2020** & **1991–2020** & **2014** & **2019** & **2020** & **1991–2020** \\ \hline May & 13.0 & 11.6 & 10.0 & 13.0 & 32.7 & 142.8 & 95.1 & 60.4 \\ June & 14.4 & 20.2 & 17.6 & 16.3 & 50.8 & 120.6 & 98.4 & 72.6 \\ July & 20.4 & 17.1 & 17.3 & 18.6 & 37.3 & 56.3 & 84.4 & 86.8 \\ August & 17.1 & 18.5 & 18.5 & 18.0 & 86.1 & 55.9 & 53.1 & 61.5 \\ September & 13.6 & 13.7 & 14.4 & 13.0 & 25.9 & 78.7 & 34.6 & 57.3 \\ \hline May–September & 15.7 & 16.2 & 15.6 & 15.8 & 232.8 & 454.3 & 365.6 & 338.6 \\ \hline \end{tabular}
\end{table} 
Table 2: Weather conditions in 2014, 2019, and 2020 and in the 1991–2020 reference period, according to the Agricultural Experiment Station (AES) in Tomaszkowo. \begin{table}
\begin{tabular}{c c c c c c c c c c c c} \hline  & \multicolumn{2}{c}{**Yield**} & \multicolumn{2}{c}{**DM \({}^{\ddagger}\)**} & \multicolumn{2}{c}{**CA \({}^{\ddagger}\)**} & \multicolumn{2}{c}{**CF \({}^{\ddagger}\)**} & \multicolumn{2}{c}{**CE \({}^{\ddagger}\)**} & \multicolumn{2}{c}{**NDF \({}^{\ddagger}\)**} & \multicolumn{2}{c}{**ADF \({}^{\ddagger}\)**} & \multicolumn{2}{c}{**ADC \({}^{\ddagger}\)**} & \multicolumn{2}{c}{**NPC \({}^{\ddagger}\)**} \\ \cline{2-13}
**Treatment (0)** & \multicolumn{2}{c}{**Mg Na\({}^{-1}\)**} & \multicolumn{2}{c}{**g Mg Na\({}^{-1}\)**} & \multicolumn{2}{c}{**Mg Na\({}^{-1}\)**} & \multicolumn{2}{c}{**Mg Na\({}^{-1}\)**} & \multicolumn{2}{c}{**Mg Na\({}^{-1}\)**} & \multicolumn{2}{c}{**Mg Na\({}^{-1}\)**} & \multicolumn{2}{c}{**Mg Na\({}^{-1}\)**} \\ \hline \multicolumn{1}{c}{1.