Abstract
As dead stumps of Oryzacae grasses like orchard-grass are often observed on meadows like converted fields from lowland paddies after first summer of utilization, orchardgrass was sown (seed from Snow Brand Seed Co.) on experimental grassland of Toyama Livestock Experiment Station on September 26, 1963 to check how utilization methos like cutting can reduce summer wilt and elevate grass productivity thereafter. Sowing was made on point at 10×10cm. Cutting methods taken were as follows: 1. Cut at 5cm from ground when grass reached 20cm high (abbreviated as 20-5, same below), 2. " 10cm " " " 20cm (20-10), 3. " 5cm " " " 35cm (35-5), 4. " 10cm " " " 35cm (35-10), 5. " 5cm " " " 50cm (50-5) and 6. " 10cm " " " 50cm (5-10). Six treatments above were replicated three times, one plot each cccupying 2 × 2m=4m^2. 1) Among cutting height taken, low cutting compared with high one always produced slower regrowth after cutting, spending more days for recovery. It also made stems markedly decrease in number in warmer summer season and ultimately produced more withered stumps, thus allowing weeds to, invade the plots with low forage yields. 2) Percentages of withered stumps after summer in respective treatment shown in increasing order were 20-10…20.1 %, 50-10…40.9%, 35-10…52.6%, 50-5…72.8%, 20-5…92.0% and 35-5…98.0%. In treatmnets 20-5 and 35-5, it looked as: if no stumps survied but in 20-10 about 80% survived. And the percentage in none cutting plot as control was 59.0%. 3) The highest forage yield in each plot was shown in treatment 35-10 as air dry weight 1, 906.6g/1. 96m^2 by 6 cuttings. Others shown in decreasing order were treatment 20-10…1, 714.8g with by 14 cuts, 50-10…1, 673. 3 g by 3 cuts, 35-5…1, 647.0g by 4 cuts, 50-5…1, 616.4 by 8 cuts and 50-5…1, 422.1g by 3 cuts respectively. From the results shown above, it may be considerd that in earlier stage of grass regrowth, high cutting and frequent utilization are desirable.
