Grazing and Grassland Management Good Grassland Management involves the following: Finding out the amount of herbage required. The application of ample fertiliser to achieve this. Maximising the DMD of the sward by managing grazing and conservation. The amount of herbage output required is calculated by the amount / type of stock on the farm. Generally 1 livestock unit consumes 12 tonnes of herbage dry matter per year.

Livestock Units A livestock unit (LU) is a measurement of livestock grazing. One livestock unit is the equivalent of one dairy cow or one suckler cow It is used to determine how much grazing and winter fodder is needed on a farm As said earlier 1 LU requires 12 tonnes of herbage annually and using this value determines the total quantity of herbage required on the farm for the herd

Livestock Units 1 dairy/suckler cow = 1LU Cattle < 1 year = 0.4LU Cattle 1 – 2 years = 0.6 LU Sheep = 0.15LU

Fertiliser Requirements The amount of fertiliser applied to grassland greatly depends on the grazing level and the level of establishment. Fertiliser should be applied to newly established grassland where grazing is light, in the following proportions: N – 48 kg / ha P – 20 kg / ha K – 38 kg / ha Intensely grazed pastures should receive additional fertiliser as outlined by Teagasc.

Fertilizer Requirements Land set aside for silage or hay should also be fertilised in advance of each harvest. Hay is only cut once over the grazing season while silage can be cut repeatedly. The following is recommended by Teagasc: Crop Fertilizer Application (kg / ha) Silage 1st Cut N P K 2nd Cut 3rd Cut 1 Cut 100 35 150 - - - 2 Cuts 125 35 150 88 9 38 3 Cut 150 44 188 100 18 75 81 - - Hay 75 26 112

Managing Grazing Good grazing management requires young leafy digestible grass to be available for grazing at all times. An efficient system of rotational grazing allows the farmers achieve this. There are various systems available including Paddock Grazing, Strip Grazing, Block Grazing, Set Stocking, Creep Feeding and Mixed Grazing.

Grazing Management Paddock Grazing Paddock grazing is the most efficient form of rotational grazing, whereby 20 – 25 paddocks are created using electric fencing. The paddocks are created to suit the herd, using the rule: 120 cows will graze 1 ha of young leafy grass in one day. The herd graze one paddock per day in a rotational manner. Nitrogen is applied to the paddocks as soon as they are removed.

Grazing Management By the time they return to the paddock, the grass should be at the height of its digestibility, (normally takes 3 weeks) This system can be quite expensive but is widely used on dairy farms. Silage fields are usually kept independent of the paddock system, as the small areas may be difficult to cut. Paddock grazing systems are sometime called rotational grazing systems

Roadway

Paddock Grazing Advantages Disadvantages Fresh, highly digestible grass is available every day No grass wasted Excess grass produced can be saved as silage Expensive to set up as roadways, access to each paddock need to be created. Fencing and water supply needed for each paddock If paddocks small, is difficult to cut for silage

Grazing Management Strip Grazing This system involves the use of a movable electric fence, to give the stock a fresh strip of leafy grass per day. Grass strips are fertilised in the same way as the paddock system. A back fence should be used however, as to allow the grass recover sufficiently. This system is cheap, but requires a lot of labour time and is therefore rarely used by itself.

Strip Grazing Advantages Disadvantages Fresh, leafy grass is available for grazing each day No wastage of grass as each strip is grazed bare Grass is not damaged while re-growing as it is not accessible to livestock High labour required to move livestock, fencing and a movable water supply each day Use of a fixed water supply means part of field has to be left as access to water supply and this land can be damaged by constant tramping

Grazing Management Set Stocking This is simplest, cheapest but least effective form of grazing management. It simply involves allowing the stock free access to all areas throughout the grazing year. This allows set – stocked areas to become patchy, with areas of highly un-productive grasses evident.

Set Stocking Advantages Disadvantages Low cost system with minimum of fencing and water troughs required Poaching is minimised as livestock not as densely packed in one area Less labour required Grass is not grazed efficiently Grass is wasted and much of it turns stemmy, leading to a reduced DMD Patchy, unpalatable grass can develop with a low digestibiliy If disease present in pasture, livestock constantly exposed to it

Grazing Management Block Grazing This system is the most common system used in Ireland, as it is cheap, effective and low on labour. It involves the division of the grazing area into blocks that provide grazing for 7-8 days. Pasture management can be improved by using strip grazing in each block. Larger blocks can be set aside for silage once or twice a year. This system is cheap and is suitable for dairy, beef and sheep grazing.

Block Grazing Advantages Disadvantages Cheaper than paddock grazing Less fencing needed Less labour required Less movement of animals Not as efficient as paddock or strip grazing

Grazing Management Zero Grazing This is a system where cattle are housed all year round Grass or other forage crops are cut and brought to the livestock, where they are fed indoors

Advantages of zero grazing Land not poached by animals Energy not wasted by animals through movement. Energy can be used for live weight gain and milk production Less chance of lameness as livestock not walking on roads Access to fresh grass at all times Topping grass is unnecessary, as all grass is cut at the same time

Disadvantages of Zero Grazing Very labour intensive Not suitable to large herds of animals as a lot of work for farmers

Creep Feeding This system involves allowing young animals access to the best grass by means of a fence with a hole only large enough for a calf or lamb. The calf or lamb can “creep” through the small opening to the good grass but the adult cannot. This allows the young animals to get the best grass, avoid worm infection and still allows the animals to suckle their mother.

Leader - Follower This basically involves allow the younger animals onto a paddock, strip or block before the adults. This again allows the younger animals to get the best grass and avoid picking up intestinal diseases. It involves less “set up” than creep feeding. It is common practice on dairy farms, when replacement heifers lead the main herd. Difference between this and creep feeding is young animals do not have access to their mothers

Mixed grazing Mixed grazing is the grazing of cattle and sheep together in the same field or paddock Advantages of mixed grazing Production levels are increased by 10 – 15 % in both cattle and sheep Tillering is increased as sheep graze closer to the ground There is less waste of grass due to the sheep’s close grazing habit Cows will not eat around their own dung. Sheep will eat this grass ensuring there is no waste and prevents grass from becoming patchy, stemmy and unpalatable Cows are less selective grazers than sheep so will eat grass species that sheep will not consume

Tillering Tillering is the development of side shoots in a plant The more side shoots or tillers that are produced by the grass plant the greater the quantity of herbage produced Tillering is encouraged by grazing pasture with sheep or light stock such as calves Topping also encourages tillering When the main shoot of the plant is grazed, this encourages the production of side shoots or tillers