Silage Tests Results

Selection of Corn Hybrids for Use as Silage

J. C. Johnson, Jr. and R. N. Gates

The information presented in the following tables is intended to help producers select corn hybrids which produce large yields of high quality silage. Consistently high yields over several locations and years reliably show a hybrid's ability to produce top yields. Primary quality factors are the proportion of grain and the digestibility of the grain and non-grain portions of the hybrid. Hybrids differ in the proportion of grain they produce.

In the past it was accepted that a hybrid with the highest proportion of grain made the highest quality silage. Research has shown that many times this is not true. In-vitro dry matter digestibility (IVDMD) is a measure of the percentage of a feedstuff the animal can digest and utilize. IVDMD values for grain are high and do not vary greatly among hybrids. IVDMD values for the non-grain portion (fodder) of the corn plant are lower but much more variable among hybrids compared to the grain portion. Thus, one hybrid with a lower proportion of grain could have high quality (digestibility) because the IVDMD of its fodder portion was much higher than another hybrid having a higher proportion of grain but a much lower IVDMD of its fodder portion.

The yield and IVDMD of the whole plant (fodder and grain) should be considered when selecting a hybrid to produce silage. Some dairy farmers may be tempted to sacrifice yield and use a hybrid with a very high proportion of grain to increase the digestibility (energy density) of the silage. Feeding such high grain content silage plus the concentrate feeds usually fed can overload the rumen with starch and lead to serious acidosis and associated health problems plus abnormal composition of milk produced. The most desirable silage hybrids for dairy cattle should produce top yields of highly digestible silage. To obtain this high digestibility and maintain high silage intake and normal digestive function, emphasis should be directed to high digestibility of fodder with a lower proportion of grain rather than trying to obtain high digestibility by maximizing the proportion of grain.






Summary of Evaluations of Corn Hybrids for Silage Blairsville, Calhoun, Griffin, and Tifton, Georgia, 1997

----------------------------------------------------------------------------------------------------------------- Quality Factors1 ----------------------------- IVDMD Dry Matter Yield --------------------- ------------------------------------------------ Company or Hybrid Maturity Whole Grain Statewide Brand Name No. Class Fodder Grain Plant2 Portion Average Blairsville Calhoun Griffin Tifton ----------------------------------------------------------------------------------------------------------------- -------- % -------- % ---------------- tons/acre------------------- Short and Mid-Season AgraTech 9250 M 62.5 91.1 73.9 40 . . . 11.4 11.3 AgraTech ATX999 M 62.6 90.7 76.3 49 . . . . 11.5 AgriPro AP9909 M 56.8 89.7 73.9 52 . . . . 12.2 Asgrow RX 938 M 60.3 92.4 75.4 47 . . . . 12.0 DeKalb DK 683 M 57.5 92.0 73.5 47 10.5 10.5 9.9 10.2 11.3 DeKalb DK 687 M 60.1 91.4 74.6 46 . . . . 12.3 DeKalb DK 706 M 58.5 91.2 72.8 44 . . . . 11.3 DeKalb DK 714 M 57.1 90.7 73.4 49 . . . . 11.0 DeKalb DK 720S M 57.1 90.9 73.2 48 . . . . 12.1 HyPerformer AP 9707 S 58.0 91.0 76.0 55 . . . . 11.0 HyPerformer HS 9977 M 59.0 89.0 74.0 50 . . . . 10.8 HyPerformer HY 9919V M 59.6 91.3 75.8 51 . . . . 10.8 Mycogen TMF 113 S 59.7 91.4 75.6 50 . . . . 11.8 Northrup King 4868 M 59.1 90.8 72.7 43 10.2 9.5 9.8 10.7 11.0 Northrup King N 83-R7 M 62.4 91.1 77.1 51 9.4 9.7 8.9 7.7 11.2 Northrup King N 8811 M 57.3 89.5 73.7 51 11.0 10.9 11.6 10.6 10.8 Northrup King NX 7305 S 60.5 90.6 75.3 49 9.9 10.5 9.6 8.5 11.1 Pioneer 3154 M 60.1 89.6 73.6 46 11.3 12.0 11.0 9.6 12.5 Pioneer 3223 S 59.4 91.3 75.3 50 9.5 8.8 9.5 9.0 10.8 Terra E 1186 M 60.5 90.8 76.1 51 10.0 9.0 10.0 9.3 11.6 Average 59.4 90.8 74.6 48 10.2 10.5 10.0 9.7 11.4 LSD at 10% Level 2.0 1.2 1.8 4 - 1.4 0.6 9.7 1.0 Std. Err. of Entry Mean 0.9 0.5 0.8 2 - 0.5 0.2 0.4 0.4 Full-Season AgraTech 1010 F 55.2 90.6 70.4 43 . . . . 11.0 AgraTech 1177 F 49.5 92.7 65.9 38 . . . 11.9 11.7 DeKalb DK 743 F 55.7 91.6 74.1 51 . . . . 10.9 Greenwood 835 F 53.5 90.6 68.6 41 . . . . 12.8 Greenwood 7401 F 55.8 91.4 71.0 43 . . . . 11.0 Greenwood 7408 F 52.3 91.0 67.8 40 . . . . 10.6 Northrup King McNair 508 F 55.4 90.1 69.6 41 . . . . 10.6 Pioneer 3085 F 53.9 91.8 73.2 51 11.4 11.7 11.7 11.4 10.8 Pioneer 3098 F 56.4 89.5 67.2 33 . 14.5 . . 11.7 Terra TR 1226 F 56.5 90.8 73.0 48 9.4 8.5 9.3 9.6 10.2 Average 54.4 91.0 70.1 43 10.4 10.5 10.5 11.0 11.1 LSD at 10% Level 3.2 1.1 1.8 2 - 1.4 0.6 1.1 0.9 Std. Err. of Entry Mean 1.3 0.4 0.8 1 - 0.5 0.2 0.4 0.4 ----------------------------------------------------------------------------------------------------------------- 1. Quality factors taken from the replicated silage trial at Tifton. 2. This variable is calculated to reflect the relative contribution of each component using the following formula: whole plant IVDMD = fodder IVDMD X percent fodder + grain IVDMD X percent grain. Bolding indicates entries performing equally to highest performing entry within a column based on Fisher's protected LSD (P = 0.10).





Tifton, Georgia: Evaluation of Corn Hybrids for Silage, 1997, Irrigated

----------------------------------------------------------------------------------- Forage Yield 2-Year Company or Hybrid Maturity ------------ Dry Grain Average Dry Brand Name No. Class Dry Green Matter Portion Forage Yield ----------------------------------------------------------------------------------- --tons/acre-- % % tons/acre Short and Mid-Season Pioneer 3154 M 12.5 29.2 42.7 46 11.8 DeKalb DK 687 M 12.3 32.7 37.6 46 11.9 AgriPro AP9909 M 12.2 27.5 44.3 52 . DeKalb DK 720S M 12.1 33.2 36.6 48 . Asgrow RX 938 M 12.0 33.2 36.1 47 . Mycogen TMF 113 S 11.9 27.8 42.5 50 11.9 Terra E 1186 M 11.6 28.3 40.9 51 . AgraTech ATX999 M 11.6 31.3 36.9 49 11.8 DeKalb DK 706 M 11.3 28.4 39.7 44 11.9 DeKalb DK 683 M 11.3 31.0 36.3 47 11.8 AgraTech 9250 M 11.3 31.5 35.7 40 11.1 Northrup King N 83-R7 M 11.2 28.3 39.5 51 . Northrup King NX 7305 S 11.1 27.8 40.0 49 . HyPerformer AP 9707 S 11.1 29.5 37.7 55 11.3 DeKalb DK 714 M 11.0 27.3 40.3 49 11.3 Northrup King 4868 M 11.0 32.4 33.9 43 11.8 HyPerformer HS 9977 M 10.9 29.5 36.6 50 11.1 Pioneer 3223 S 10.8 28.4 38.1 50 11.8 Northrup King N 8811 M 10.8 28.2 38.1 51 11.3 HyPerformer HY 9919V M 10.8 28.2 38.1 51 11.2 Average 11.41 29.7 38.6 48 11.6 LSD at 10% Level 1.0 1.9 2.6 4 - Std. Err. of Entry Mean 0.4 0.8 1.1 2 - Full Season Greenwood 835 F 12.8 36.8 33.6 41 . Pioneer 3098 F 11.7 35.0 33.3 33 12.1 AgraTech 1177 F 11.6 33.8 34.5 38 13.4 AgraTech 1010 F 11.0 32.2 34.2 43 . Greenwood 7401 F 11.0 33.5 32.9 43 . DeKalb DK 743 F 11.0 30.2 36.2 51 11.6 Pioneer 3085 F 10.8 34.9 30.9 51 11.3 Northrup King McNair 508 F 10.7 32.0 33.3 41 12.6 Greenwood 7408 F 10.6 32.0 33.0 40 . Terra TR 1226 F 10.2 27.0 37.9 48 11.5 Average 11.12 32.7 34.0 43 12.1 LSD at 10% Level 0.9 2.2 2.3 2 - Std. Err. of Entry Mean 0.4 0.9 0.9 1 - ----------------------------------------------------------------------------------- 1. CV = 7.3%, and df for EMS = 57. 2. CV = 6.6%, and df for EMS = 26. Bolding indicates entries yielding equal to highest yielding entry within a column based on Fisher's protected LSD (P = 0.10). Planted: March 19, 1997. Harvested: Short and Mid-Season hybrids - July 22, 1997. Full Season hybrids - July 23, 1997. Population: 28,000 plants/acre in 30" rows. Soil Type: Tifton loamy sand. Soil Test: P = High, K = Medium, and pH = 6.5. Fertilization: 60 lb N, 120 lb P2O5, and 180 lb K2O/acre preplant and 216 lb N/acre applied as a sidedress. Previous Crop: Soybean. Management: Moldboard plowed, subsoiled, and rototilled; Sutan, Accent, and two cultivations used for weed control; Lorsban used to control soil insect pests; irrigated 8 times totaling 5 inches. Test conducted by A. E. Coy and M. Pippin.





Griffin , Georgia: Evaluation of Corn Hybrids for Silage, 1997, Irrigated

----------------------------------------------------------------------------------- Forage Yield 2-Year Company or Hybrid Maturity ------------ Dry Grain Average Dry Brand Name No. Class Dry Green Matter Portion Forage Yield ----------------------------------------------------------------------------------- --tons/acre-- % % tons/acre AgraTech 1177 F 11.9 18.7 63.3 49 12.8 AgraTech 9250 M 11.4 18.5 61.9 47 . Pioneer 3085 F 11.4 19.5 58.9 55 . Northrup King 4868 M 10.7 17.5 61.5 39 10.8 Northrup King N 8811 M 10.6 17.8 59.4 55 10.2 DeKalb DK 683 M 10.2 13.9 73.7 47 . Terra TR 1226 F 9.6 13.1 73.8 52 11.9 Pioneer 3154 M 9.6 15.0 64.2 42 10.5 Terra E 1186 M 9.3 13.4 69.6 51 . Pioneer 3223 S 9.0 13.1 69.2 48 10.7 Northrup King NX 7305 S 8.5 13.8 61.5 44 . Northrup King N 83-R7 M 7.7 13.2 58.5 46 . Average 10.01 15.6 64.6 48 11.2 LSD at 10% Level 1.1 1.9 6.8 3 - Std. Err. of Entry Mean 0.4 0.8 2.8 1 - ----------------------------------------------------------------------------------- 1. CV = 9.4%, and df for EMS = 32. Bolding indicates entries yielding equal to highest yielding entry within a column based on Fisher's protected LSD (P = 0.10). Planted: April 3, 1997. Harvested: September 12, 1997. Population: 28,000 plants/acre in 30" rows. Soil Type: Cecil sandy clay loam. Soil Test: P = High, K = High, and pH = 6.5. Fertilization: 49 lb N, 98 lb P2O5, and 147 lb K2O/acre preplant and 200 lb N/acre applied as a sidedress. Previous Crop: Soybean. Management: Moldboard plowed and rototilled; Aatrex and Lasso used for weed control; irrigated 9 times totaling 6.0 inches. Test conducted by J. L. Day.





Calhoun, Georgia: Evaluation of Corn Hybrids for Silage, 1997, Irrigated

----------------------------------------------------------------------------------- Forage Yield 2-Year Company or Hybrid Maturity ------------ Dry Grain Average Dry Brand Name No. Class Dry Green Matter Portion Forage Yield ----------------------------------------------------------------------------------- --tons/acre-- % % tons/acre Pioneer 3085 F 11.7 26.6 44.0 49 . Northrup King N 8811 M 11.6 25.2 46.4 48 . Pioneer 3154 M 11.0 20.1 53.8 44 9.9 Terra E 1186 M 10.0 20.7 48.6 52 . DeKalb DK 683 M 9.9 20.8 47.5 44 . Northrup King 4868 M 9.8 21.7 45.3 45 9.5 Northrup King NX 7305 S 9.6 19.6 49.2 45 . Pioneer 3223 S 9.5 17.6 54.2 47 9.6 Terra TR 1226 F 9.3 19.9 46.8 46 . Northrup King N 83-R7 M 8.9 18.7 47.7 45 . Average 10.11 21.1 48.4 46 9.7 LSD at 10% Level 0.6 1.5 3.5 03 - Std. Err. of Entry Mean 0.2 0.6 1.5 01 - ----------------------------------------------------------------------------------- 1. CV = 5.0%, and df for EMS = 25. Bolding indicates entries yielding equal to highest yielding entry within a column based on Fisher's protected LSD (P = 0.10). Planted: April 10, 1997. Harvested: August 29, 1997. Population: 28,000 plants/acre in 30" rows. Soil Type: Rome gravelly clay loam. Soil Test: P = Very High, K = High, and pH = 6.3. Fertilization: 75 lb N, 90 lb P2O5, and 180 lb K2O/acre preplant and 150 lb N/acre applied as a sidedress. Previous Crop: Soybean. Management: Moldboard plowed and rototilled; Aatrex and Dual used for weed control; irrigated 4 times totaling 2.0 inches. Test conducted by J. L. Day and T. Petty.





Blairsville, Georgia: Evaluation of Corn Hybrids for Silage, 1997, Nonirrigated

----------------------------------------------------------------------------------- Forage Yield 2-Year Company or Hybrid Maturity ------------ Dry Grain Average Dry Brand Name No. Class Dry Green Matter Portion Forage Yield ----------------------------------------------------------------------------------- --tons/acre-- % % tons/acre Pioneer 3098 F 14.5 44.6 32.4 30 14.5 Pioneer 3154 M 12.0 26.4 45.3 48 10.9 Pioneer 3085 F 11.7 31.0 38.0 49 . Northrup King N 8811 M 10.9 25.4 43.2 48 . Northrup King NX 7305 S 10.5 23.7 44.0 50 . DeKalb DK 683 M 10.5 25.8 40.7 49 . Northrup King N 83-R7 M 9.7 22.5 43.1 50 . Northrup King 4868 M 9.5 21.5 44.0 45 10.1 Terra E 1186 M 9.0 19.6 45.9 48 . Pioneer 3223 S 8.8 16.6 53.1 53 8.9 Terra TR 1226 F 8.5 15.0 56.6 49 . Average 10.51 24.7 44.2 47 11.1 LSD at 10% Level 1.4 3.1 3.1 7 - Std. Err. of Entry Mean 0.5 1.2 1.3 3 - ----------------------------------------------------------------------------------- 1. CV = 10.5%, and df for EMS = 28. Bolding indicates entries yielding equal to highest yielding entry within a column based on Fisher's protected LSD (P = 0.10). Planted: May 14, 1997. Harvested: October 8, 1997. Population: 24,000 plants/acre in 30" rows. Soil Type: Bradson clay loam. Soil Test: P = High, K = Medium, and pH = 6.3. Fertilization: 90 lb N, 90 lb P2O5, and 90 lb K2O/acre preplant and 100 lb N/acre applied as a sidedress. Previous Crop: Soybean. Management: Moldboard plowed and disked; Aatrex, Bicep and one cultivation used for weed control. Test conducted by J. L. Day and H. D. Garrett.