Row Spacing, Hybrid, and Plant Density Effects on Corn Silage Yield and Quality

Abstract

Considerable interest exists in New York for narrow row corn (Zea mays L.) silage production because farmers, who converted from 30- to 15-in. row spacing, report yield increases of 3 to 4 tons/acre. We evaluated eight hybrids at densities of 18 000, 24 000, 30 000, 36 000, and 42 000 plants/acre in 1994, 1995, and 1996 to compare yield, quality, and economics of corn silage production at 15- and 30-in. row spacings. When averaged across years, hybrids, and densities, corn silage yielded 24.9 tons/acre at 15 in. and 23.9 at 30 in. row spacing. Row spacing × hybrid and row spacing × plant density interactions did not exist. When averaged across years, hybrids, and row spacings, maximum economic yields occurred at about 39 500 plants/acre. In vitro true digestibility (IVTD), however, had a 0.1% decrease and neutral detergent fiber (NDF) had a 0.13% increase per 1000 plant/acre increase. Consequently, estimated maximum economic milk yield occurred at about 35 000 plants/acre. Partial budget analyses indicated that farmers who produce 200 acres of corn silage might expect a slight loss in annual net farm income (-$696) with the conversion from 30- to 15-in. row spacing. Farmers, who produce 400 and 800 acres of silage, might expect modest ($3116) and significant gains ($11 624) in annual net farm income, respectively. We have initiated field-scale trials on a dairy farm to further assess the potential for narrow row corn silage production in New York.