Belated removal of animals from a paddock in an intensively managed grazing system is a major obstacle and will cause the system to fail. Physiologically, it takes a forage plant an equal number of rest days to grow from 2-inches to 4-inches in height as it does for the same plant to grow from 4- inches to 8-inches in height. When managing grazing, care must be taken to not overgraze. From this point until the forage population or sward reaches and exceeds approximately 10-inches in height, grazing should be either prohibited at best or at least limited. At approximately 43 degrees the grasses and other forages activate or wake up from winter dormancy. The second critical time in plant physiology to be considered during grazing management is when the average high air temperature (subtract the 24 hour minimum from the 24 hour maximum) becomes 43 degrees each spring. It is recommended that phosphorus and sulfur levels be checked via soil sampling in August and fertilizing, if needed, be accomplished in early September. This time of year will be detrimental to the following year’s production. It should also be noted that the plant physiology calendar year starts in the fall (September in the Pacific Northwest). It is recommended to not graze below the 2 or 3-inch level at any time during the growing season. This less intensive system will not maximize paddock production, but will lower the management level and provide adequate quality forage for beef cows, dry cows and stocker cattle. A less intensive grazing system consists of 5 to 10 days of grazing with the same 20 to 30 day rest period for the paddock. Ideally, intensive grazing closely resembles the harvesting of hay and is thus close to ideal for forage plant physiology. This requires 16 to 20 paddocks and will provide high- quality pasture needed by growing animals and dairy cows. The ideal rotational grazing system consists of 1 to 2 days of grazing with 20 to 30 days of rest for each field or paddock. July and August heat may depress forage growth to a level where 50 percent more acreage is needed to feed the same animal. Spring growth from half of one acre may be adequate to feed young heifers, dry cows, low milk producers or beef stockers. The amount of pasture needed depends on pasture quality, animal size and type, season and species of forage in the pasture. Pastures can be a useful source of forage on property that is unsuitable for other crops. To be profitable, producers have an increased dependency on forages, grazing and pastures. Lengthening the grazing season by using practices such as stockpiling forage or planting annuals for forage can greatly reduce production costs for a wide variety of livestock species. New and changing management practices in the dairy industry allow forage to be anywhere from 20 to 80 percent of a cow’s diet at any time in her life. Forages make up 51 percent of horses’ diet. Sheep and goats obtain greater than 80 percent of their nutrition from forage, while 73 percent of beef cattle nutrition is from forages. Pastures furnish 36 percent, harvested forages contribute 18 percent and the balance of livestock feed is obtained from concentrate feed including grain and protein supplements.Īs expected, the importance of each kind of feed varies with the type of livestock. Forage crops provide 54 percent of the feed consumed by livestock in the United States.
0 Comments
Leave a Reply. |