The study was

carried out to determine the chemical composition and

production yield of dry matter and nutritional content per area

in shoots 91 to 161 days old, and to explore the options for

harvest silage. The study took place at the Alfredo Volio

Mata Experimental Station of the University of Costa Rica.

The first samples were taken at 91 days and were re-taken

every 14 days until they were 161 days old. Biomass

production was measured and the content of dry matter, crude

protein, ashes, neutral detergent fiber increased as the

maturity of the plants increased, to a rate of 0.19%/day in

leaves and 0.26%/day in stems, for a 0.22%/day in the whole

plant. The yield of green matter reached its maximum at 135

days, the leaves at 121 days, and the stems at 144 days. The

maximum production of dry matter, crude protein and neutral

detergent fiber per hectare was obtained from shoots of 130

to 135 days old. The best quality was found at 91 days, with

12% of dry matter and 14% crude protein. From that age on,

the accumulation of dry matter increased at a rate of 62

kg/ha/day (a concentration of 2% every 10 days), of which 48

kg were of neutral detergent fiber and an average of 2 kg of

lignin. The content of crude protein decreased 1% every 10


Keywords: Sorghum almum, quality, yield, silage.