Even higher plant populations could obtain higher yield of green weight, but this practice produces little advantage in dry weight. Typically grain yield decreased drastically at these extremely high plant populations. Many workers have reported consistent dry matter yield increases with increasing plant population. Quality changes have been less consistent. In general, as plant populations increase, fiber levels increase and digestibility decreases.
Some studies report no significant silage quality changes over a fairly wide range of populations.
High and low quality hybrids were evaluated at five plant populations between 18,000 to 42,000 plants per acre. Significant but small changes in quality were observed. Neutral detergent fiber and acid detergent fiber increase slightly as plant population increased. Crude protein and in vitro digestibility decreased as plant population increased. Milk per acre increased until 30,000 plants per acre and did not change with higher plant densities.