Effects of Cutting Height and Trampling over Stubbles of the First Crop on Dry Matter Yield in Twice Harvesting of Forage Rice

The effects of harvesting at three heights of cutting and four stages of development on the dry matter yield and persistency of intermediate wheatgrass, Agropyron intermedium (Host.) Beauv., bromegrass, Bromus inermis Leyss., and reed canarygrass, Phalaris arundinacea L., were studied at two sites on irrigated land.The dry matter yield of all species decreased with increasing heights of cutting, and increased with advancing maturity at the time of taking the initial harvest. Highest yields were obtained from all species when cut at a height of 3.8 cm during the seed stage of development. However, this height of cutting resulted in the highest degree of winter injury and the most rapid stand deterioration. Bromegrass was less sensitive to variation in cutting height than intermediate wheatgrass or reed canarygrass. On well-drained, irrigated land, intermediate wheatgrass yielded significantly more forage than either bromegrass or reed canarygrass.The application of a regression analysis to the study of significant interactions among management factors and species within a single test proved to be a very useful statistical approach.

Download Full-text

Effects of seeding density, cutting height and month of harvest on the dry matter yield and protein content of Ubon Stylo

The Journal of Agriculture of the University of Puerto Rico ◽

10.46429/jaupr.v99i2.3030 ◽

1969 ◽

Vol 99 (2) ◽

pp. 147-156

Author(s):

Jorge Olivares ◽

Elide Valencia ◽

Rafael Ramos-Santana

Keyword(s):

Dry Matter ◽

The Other ◽

Seeding Density ◽

Second Phase ◽

Dry Matter Yield ◽

Seeding Rate ◽

Four Levels ◽

Time Of Year ◽

High Yields ◽

Cutting Height

Four levels of seed were used for establishment of Ubon Stylo (Stylosanthes guianensis var. vulgaris x var. pauciflora) in the first phase of this research, and in the present second phase, this same variable plus three cutting heights and four months of harvest at 90-d intervals were evaluated as to their effects on forage dry matter yield (DMY) and crude protein (CP) content. The seeding levels (5, 10, 15 and 20 kg/ha) constitute the main plots; cutting heights (10, 15 and 20 cm) formed the subplots; and months of harvest (March, June, September and December) the sub-subplots. Statistical analysis revealed that DMY was not significantly influenced by cutting height or by the interactions of this variable with each of the other two. Month of harvest did exert a significant effect (P<0.05) on DMY, and seeding density showed a similar tendency (P<0.063); also an interaction (P<0.05) between these two variables was detected. Mean DMY, expressed as annual equivalent (kg/ha), corresponding to the four consecutive harvests from March to December were: 5,949; 11,285; 8,105 and 6,543; with a general mean of 7,970. Values of DMY corresponding to the four progressive seeding rates from 5 to 20 kg/ha seed were: 7,488; 8,347; 8,375 and 7,672 kg/ha. The seeding rate x harvest interaction is illustrated by the fact that the highest DMY at the June harvest (13,975 kg/ha) was obtained with 15 kg/ha seed, whereas the maximum DMY at the other three harvests corresponded to the 10 kg/ha seeding rate. The general mean of the forage CP content was 13.4% and no significant effects were exerted by the three factors under study or their interactions. The present results confirm the earlier conclusion that 10 kg/ha is the optimum seeding rate for establishment of Ubon Stylo to promote a high DMY without incurring in unnecessary additional expense. Furthermore, the high yields obtained in the summer season suggest that the cutting interval could be shortened to improve the CP content at this time of year.

Download Full-text