For sustainable and profitable agricultural production and conservation of environment, wildlife and amenity resources, it is important to use appropriate plant species in respective grassland systems. In recent years in Japan, there has been increased interest in using centipedegrass (Eremochloa ophiuroides (Munro) Hack.) as a low‐input plant for soil conservation and gazing purposes. The history of cultivation and use of centipedegrass in Japan is not long and thus, detailed information on growth habit, establishment, management and utilization of this grass is lacking. In the present paper, the distribution and occurrence of centipedegrass are traced and the growth habit and importance are discussed. Since its introduction into the USA from China in 1916, it is increasingly being used as a popular turfgrass. This grass forms a relatively short and highly dense sward with rapidly spreading leafy stolons, which is advantageous in terms of soil conservation, particularly in high rainfall and sloped areas. This grass can also be used for grazing due to high leafiness and high palatability by animals. Therefore, there may be real potential in utilizing centipedegrass for multipurpose usages and the usefulness of this grass needs reevaluation.

A herd of 28-33 Japanese Black cows (Bos taurus) were allowed to graze on an experimental plot comprising monoculture swards of centipedegrass (Eremochloa ophiuroides) and bahiagrass (Paspalum notatum) (0.39 and 0.61 ha, respectively) for 3-5 days each month (from 0850 to 1600 hours) between May (late spring) and October (mid-autumn). On a monthly basis, the animals showed an increasing trend to select centipedegrass in preference to bahiagrass as the relative crude protein (CP) concentration of the former increased relative to the latter. On a daily basis, the animals showed a decreased selectivity for centipedegrass with the progression of grazing days, as centipedegrass sward lost both quantity and quality faster than bahiagrass sward under higher degrees of defoliation. Animals maintained similar bite rates on the two swards by modifying feeding station behavior as soon as they switched between the swards, i.e., they increased the number of bites per feeding station and decreased the number of feeding stations selected per unit grazing time soon after switching to centipedegrass, with the reverse process occurring soon after the switch to bahiagrass. The results show CP concentration to be a partial forage factor influencing animals' choice between tropical grasses growing as patches. The results also demonstrate that animals have an ability to adapt their foraging behavior flexibly and rapidly to varying types of vegetation.

SU MMARYRelationships between sward height and short-term ingestive behaviour of cattle were examined for two tropical stoloniferous grasses with contrasting growth forms : centipede grass (Eremochloa ophiuroides (Munro) Hack.; (CG) ; strongly prostrate) and bahia grass (Paspalum notatum Flu¨gge; (BG) ; more erect). Turves (500r500 mm) were extracted from field monoculture swards of each grass after the varying duration of re-growth, and presented to animals for a short period (10 bites) to measure bite dimensions (area, depth and volume), bite mass, time per bite and intake rate. In the same re-growth period, CG was always shorter and denser than BG. Bite dimensions, the bite mass and the intake rate of animals increased at a declining rate as the sward height increased for both grasses, showing a tendency for a steeper initial increase, an earlier plateau and a lower maximum in CG than in BG. Due to the difference in the shape of the intake rate response, animals on BG were estimated to require a longer grazing time than those on CG to attain the same daily herbage intake, when the sward is shorter than about 200 mm. The sward height below which the daily intake of animals may be restricted was lower for CG (61-70 mm) than for BG (71-92 mm). The results indicate an advantage of strongly prostrated, highly dense grasses (e.g. CG) over more erect, less dense grasses (e.g. BG) when grazed at a relatively low height (<200 mm). In relation to increasing bite mass, the time per bite pooled over CG and BG was constant until the bite mass reached a critical value (0 . 55 g dry matter (DM)) and thereafter increased linearly with the bite mass, confirming that cattle are able to perform compound jaw movements that gather herbage into the mouth (manipulative jaw movement) and chew herbage already in the mouth (chewing jaw movement) within one cycle of opening and closing of the jaws.

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Miscanthus sinensis, a tall cespitose warm‐season perennial grass, occurs widely in tree plantations across Japan as a major weed. A 4‐year grazing trial was conducted in a young Chamaecyparis obtusa (an evergreen conifer) plantation in south‐western Japan, in an effort to evaluate forest grazing as a management practice to utilize and control M. sinensis and to deepen a mechanistic understanding of the responses of this grass to herbivory. The plantation was continuously stocked by Japanese Black cattle during the grazing season from May–November (July–November in the first year) at rates of 0.38–0.63 animals ha−1. M. sinensis was always the major species selected by animals, with most of the plants (80–90%) in the paddocks being defoliated during the grazing season. Reflecting these, M. sinensis plants declined with time under grazing, mainly in shoot number per tuft and partly in leaf appearance rate and the weight of the youngest fully expanded leaf, leading to a drastic decrease in production of leaves (laminae) as a photosynthetic organ and a main feed component for animals. Animals did little fatal damage to C. obtusa trees. Performance of animals was acceptable for cows that had experienced forest grazing in preceding years, but needed improvement for inexperienced heifers and calves. The results demonstrate the potential value of cattle grazing in utilizing and controlling M. sinensis in young tree plantations, which enables multifunctional land use linking forest and animal industries. Further studies are necessary to explore the optimum grazing intensity that balances effective control and extended utilization of the grass.