GRAZING NOTEBOOK
The Irish Farmers Journal Your Partner for Profit Grasswatch - the first page every dairy farmer needs to read every week Dairy Coverage GrassWatch The only comprehensive weekly grassland management and growth rate guide available Dairy Feature Farmer profiles, research updates, profitability targets, and milk leagues. Farmer Focus Farmers speaking for themselves on the important issues from inside the farm gate Management Column Weekly advice and solutions
Table of Contents Foreword...2 Grazing Guidelines throughout the year...3 Spring Grassland Management...4 Mid Season Grassland Management...6 Autumn Grassland Management...7 Section 1 How to calculate DM Yield (cover)...8 Section 2 Estimating grass dry matter% (DM)...9 Section 3 Relationship between post-grazing heights and residuals...10 Section 4 Calculating daily demand at grass...10 Section 5 Calculating target pre-grazing yield...11 Section 6 Completing a farm cover...12 Section 7 How to calculate the quantity of grass per cow...13 Section 8 Calculating grass growth...14 Section 9 Target grass covers...15 Section 10 Nitrogen application throughout year...16 Section 11 Step by step guide to master the Grass Wedge...18 Section 12 Understanding your Grass Wedge...20 Example Farm Walk Recorder...32 Example Manual Grass Wedge...33 Example Calculating Farm Cover...34 Published by Teagasc and The Irish Farmers Journal. First Published June 2009 Copyright 2009
Foreword The competitive advantage of Irish milk production systems is based on the efficient production and utilisation of grazed pasture. Irish pastures have the potential to grow between 11 and 16 tonnes of DM per hectare per annum and grass growth is virtually year round facilitating a long grazing season. Recent advancements in grassland technology have the potential to significantly increase farm profitability through an extended grazing season and higher performance from pasture. This grassland notebook is designed to help grassland farmers adopt these technologies at farm level. The application of the information in this notebook will lead to more profitable grass-based farming. The contribution of Emer Kennedy, Adrian van Bysterveldt and Michael O Donovan in the preparation of this notebook is greatly appreciated. This publication is sponsored by the Irish Farmers Journal. Pat Dillon Head of Moorepark Dairy Production Research Centre Measuring and budgeting grass has the potential to significantly reduce variable and fixed costs and keep your business profitable in times of volatile milk price. Measuring means putting a figure on how much grass is on your farm. Budgeting means making decisions to manage the amount of grass on your farm. Measuring alone is no good. You need to make crystal clear decisions every week about how you are going to manage your grass and where your farm is relative to target. This notebook clearly spells out targets, essential calculations, and developments in grazing technology. Once farmers grasp the understanding from this notebook then the world of computers can take over and pretty much do all these calculations at the push of a button. For the first time in Ireland this notebook charts the development of the Grass Wedge as an essential tool for grazing management going forward. The Irish Farmers Journal is delighted to be associated with advancing grazing technology. Jack Kennedy Dairy Editor, Irish Farmers Journal
Grazing Guidelines Throughout the Year Spring Use spring rotation planner as outlined in this notebook, also available on http://www.agresearch.teagasc.ie/moorepark Consult farm cover targets (see Section 9) Graze to approx. 3½ to 4 cm On/off graze during wet weather Mid-season Use the Grass Wedge to determine grass supply on the farm Consult farm cover targets (see Section 9) Target pre-grazing yield: 1,100 to 1,500 kg DM/ha Graze to approx. 3½ to 4½ cm Autumn Follow Autumn grazing management guidelines outlined in this notebook Consult farm cover targets (see Section 9) Target pre-grazing yield not greater than 2,000-2,300 kg DM/ha Graze to approx. 3½ to 4½ cm On off graze during wet weather A computerised version of the grass wedge and budget is available from Teagasc.
Spring Grassland Management The following recommendations should be implemented every spring. 1. Get cows out to grass as early as possible Research at Moorepark shows that profit per cow can be increased by 2.70 per cow per day when the herd has access to grass earlier in spring. To achieve this, implement the following plan: 1. Apply 23 units of urea per acre (29 kg/ha) at the start of the period when fertilizer is allowed. 2. Apply the following grazing plan (spring rotation planner) by allocating the appropriate proportion of the farm each day during spring regardless of location, stocking rate or herd calving pattern. 3. The spring rotation planner should be used in conjunction with average farm cover targets (see Section 9). This plan can be refined to suit your own targets and this planner is available on the Teagasc Moorepark website: http://www.agresearch.teagasc.ie/moorepark Example of daily spring grazing area allocation for early turnout farms Week Start Date Fraction of farm grazed per day % of total farm area grazed at week ending 1 February 1/100 7 8 February 1/92 15 15 February 1/84 23 22 February 1/76 32 1 March 1/68 43 8 March 1/60 54 15 March 1/51 68 22 March 1/43 84 29 March 1/35 100 5 April 1/27 Rotation 2 12 April 1/19 - For example 50 cow herd with 50 grazing acres, 0.42 acres (or 1,680m 2 ) can be allocated to the herd each day during the first week of February and 2.5 acres (or 10,000m 2 ) per day by 10 April without running out of grass.
For the plan to be successful, the following are required: Stick to the target area, do not graze more or less per day A strip wire must be used to allocate grass on a 12-hour basis Grazing area should be back fenced in wet weather to avoid pasture damage Cows should be housed after three hours grazing after each milking during inclement conditions without silage unless there is not enough grass available, i.e., implement on/off grazing 2. Reduce feed costs If, after allocating the correct portion of the farm from Table 1 to the herd, the post-grazing height in the paddock is above 4cm (the height of a mobile phone lying on its side), then the herd are overfed and require no additional feed and concentrate can be phased-out to leave a grass only diet by late March. (In most cases, where stocking rates are low and grass supply is plentiful, no additional feed will be required by the herd.) 3. Improve grass swards to increase herd performance from a grass diet In April, 10% of the poorest quality pastures should be reseeded. If the farm is to be stocked at below 2.2LU/ha in future years, white clover should be included in the seed mix to reduce fertilizer input costs. 4. Increase nutrient use efficiency Apply 2,500 gallons of dilute slurry per acre in spring to replace 23 units of urea on up to 40% of the farm and use the remaining slurry before closing first-cut silage ground. This will make a significant contribution to fertilizer cost savings.
Mid-Season Grassland Management The mid-season extends from mid-april to 1 August. Use the grass wedge to determine grass supply on the farm: The grass wedge gives a visual breakdown of the herbage mass available in each paddock on the farm A line drawn from the target pre-grazing yield to the target post-grazing residual provides a guideline on surpluses and deficits When creating the grass wedge ideally have paddocks of equal size this may involve grouping small paddocks or splitting larger paddocks Quick reaction to surpluses and deficits is required during the mid-season (see Section 12). Target pre-grazing yield: 1,100 to 1,500 kg DM/ha. Graze to approx. 3½ to 4½ cm. Ensure badly grazed swards are removed as baled silage in the next rotation or are topped. Consult farm cover targets (see Section 9). Maintain high quality perennial ryegrass swards.
Autumn Grassland Management Build rotation length from 10 August; increase rotation length from 24 to 28 days by mid- September. Highest farm cover should be achieved in mid to late September (1,130kg DM/ha or 450kg DM/cow). Assess farm grass supply in early September and if necessary blanket spread the whole farm, before 15 September, with 30 kg/ha of nitrogen. Close the first paddock for spring grazing on 10 October, in slower grass growing regions closing may begin earlier. 60% of the herbage available for grazing next spring will be grown during the Autumn/Winter period. Each one day delay in closing from 10 October to 11 December reduces spring herbage mass by 15 kg DM/ha/day. Have at least 60% of the farm closed by the end of the first week of November. All paddocks should be grazed to a post-grazing height of 3½ to 4½ cm during the last rotation to encourage winter tillering. Date Rotation length (days) Comment 10 August 24 28 - Mid-September 35 40-10 October 40 45 Start last rotation (begin closing) 7 November Last rotation 60% of farm closed Late November/Early December - Farm closed
Section 1 How to Calculate DM Yield (Cover) A 0.5m x 0.5m quadrat is placed in an area that is representative of the amount of grass in the paddock Knock water off grass if wet The grass within the quadrat is cut to between 3.5 and 4cm The following equation is used to calculate the DM yield in the paddock: Weight of grass (kg) x DM% x 40,000 = kg DM/ha in the paddock Example: Grass cut within the quadrat weighs 200g (0.200 kg) (Remember to take off the weight of the empty bag) Grass DM% = 16% (0.16) 0.200 kg x 0.16 x 40,000 (there are 40,000 quadrat in a hectare) = 1,280 kg DM/ha
Section 2 Estimating Grass Dry Matter % (DM) Weather Grass DM% Continuous rain 12 15 Mixed sunshine and rain showers / second rotation 14 17 First rotation in spring /drier weather 18 19 Over a week of continuous sunshine and high temperatures 20 21 Drought conditions 22 23 DM will be higher if there is more dead (yellow) material at the base of the sward DM will be lower if the sward is green and leafy Refer to Grass Watch on the Irish Farmers Journal every week to get an idea of growth rate and DM figures in your area. Regional growth rates are also available from your local Teagasc office where grass budgeting courses are ongoing.
Section 3 Relationship between Post-Grazing Heights (Manual Rising Platemeter) and Residuals Post-Grazing Residual Equivalent Post-Grazing Height 0 50 kg 3.5 4 cm 100 200 kg 4 5 cm 200 400 kg 5 6 cm 500 kg 6 7 cm Post-grazing height measurement includes dung pad area Section 4 Calculating Daily Demand at Grass Size/Type of Cow kg DM/Cow Large Holstein herd (~ 600 kg) 19 20 High EBI Holstein herd (~ 550 kg) 17 18 Jersey Crossbred herd (450 500 kg) 16 17 Early lactation (up to 8 weeks in milk) 3-4 kg DM less than figures above and increasing (until max. intake is achieved) Calculating daily demand/ha for use in the Manual Grass Wedge page: Stocking Rate on grazing platform x Demand (from table above) = Demand/ha Example: 4 cows/ha (stocking rate) x 16 kg/cow (demand) = 64 kg demand/ha 10
Section 5 Calculating Target Pre-Grazing Yield Stocking Rate (cows/ha) x Allowance (kg DM/cow/day) x Rotation length (days) + Residual (what will be left in the paddock after grazing) Example: 4 cows/ha x 16 kg DM/cow/day x 20 days + 100 kg DM/ha (residual) = 1,380 kg DM/ha Target pre-grazing yield = 1,380 kg DM/ha Pre-Grazing Yield (kg DM/ha) Equivalent Pre-Grazing Height 700 900 6 7 1,000 1,200 7 8 1,300 1,500 8 9 1,600 1,800 10 11 >2,000 12+ 11
Section 6 Completing a Farm Cover Measure/estimate the quantity of grass in each paddock DM yield e.g., 1,400 kg DM/ha Multiply the DM yield of each paddock by the area of the paddock in ha 1,400 kg DM/ha x 1.8 ha = 2,520 kg DM in the whole paddock Repeat this for all the paddocks on the farm Sum all the paddock yields together Sum all the paddock areas together (i.e., get total area of grazing platform) in hectares This can be completed on the table below (example in the first line) Paddock DM yield (kg DM/ha) Area (ha) Total Cover 1 1400 X 1.8 = 2,520 Sum the next two columns (A) (B) To calculate farm cover Divide the sum of the quantity of grass on the farm by the total area e.g., 10,000 kg (grass on the farm) 20 ha = 500 kg DM/ha 12
Section 7 To Calculate the Quantity of Grass Per Cow Calculate stocking rate Divide the number of cows by the area available for grazing (ha) = Number of cows Area of the grazing platform (ha) Stocking Rate (cows/ha) e.g. 55 cows 20 ha (total area of grazing platform) = 2.75 cows/ha Calculate cover per cow Divide farm cover by the stocking rate = Farm cover Stocking rate = Cover per cow (kg DM/cow) e.g. 500 kg DM/ha 2.75 cows/ha = 182 kg DM/cow *Only include paddocks that are available for grazing, i.e. not those closed for silage. 13
Section 8 Calculating Grass Growth Grass growth is calculated on the paddocks that were not grazed during the week before walking the farm, i.e., if you walk the farm on a Monday use the paddocks that were not grazed from the previous Monday to calculate the grass growth rate Subtract the DM yield measured last week from the DM yield measured in the same paddock this week and divide by the number of days since the last farm walk. Repeat for all un-grazed paddocks Average all the values obtained to get the average grass growth rate. Example Week 1 (Monday): Paddock 1 = 500 kg DM/ha; Paddock 2 = 1,100 kg DM/ha Week 2 (following Monday): Paddock 1 = 800 kg DM/ha; Paddock 2 = 1,300 kg DM/ha Growth Paddock 1: 800 kg DM/ha 500 kg DM/ha = 300 7 days (since last cover) = 42.9 kg DM/day Paddock 2: 1,300 kg DM/ha 1,100 kg DM/ha = 200 7 days (since last cover) = 28.6 kgdm/day Average Growth Rate = (42.9 + 28.6) 2 = 35.8 kg DM/day This can be completed in the table below (example in first line) Paddock No. DM yield DM yield No. days between Growth rate this week last week farm walks to cover (kg DM/day) 1 800 500 7 = 42.9 14
Section 9 Target Pasture Herbage Mass (farm cover) for a Spring-Calving Herd Stocked at 2.5 cow/ha* Month Stocking Rate Growth Target Target Event (on grazing Average Cover area) Farm Cover per Cow (cow/ha) (kg DM/day) kg DM/ha kg DM/cow Feb 15 2.5 9.0 798 338 Cows out to grass by day Mar 15 2.5 37.6 568 243 Cows out fulltime May 10 4.2 88.2 840 200 Supply exceeds demand From May to August, use the Grass Wedge (farm cover should be maintained at 140 190 kg DM per cow) Aug 15 2.5 65.0 848 342 Sept 15 2.5 37.1 1130 450 Peak cover achieved Oct 15 2.5 26.8 1050 424 First paddock closed Nov 15 2.5 8.5 650 262 Supplement introduced Nov 22 2.5 2.7 560 224 House by day and night *These figures will have to be adjusted if the farm is not stocked at 2.5 cow/ha <150 kg DM per cow from May to August is dependant on responsive perennial ryegrass pastures and stocking rate 15
Section 10 Nitrogen Application throughout the Year Recommended rates of fertilizer N for grassland during the year where approximately half of the farm is cut for first-cut silage and the amount of second cut is kept to a minimum (0 30% of the grassland area). Rates of fertilizer N are presented in kg per ha (units per acre in brackets). Stocking Jan/Feb March April May June July August Sept Total Total rate (kg/ha organic N) (kg/ha) (u/ac) 155 170 0 28 (23) 43 (35) 34 (28) 34 (28) 25 (20) 164 (133) 170 180 28 (23) 28 (23) 43 (35) 34 (28) 34 (28) 25 (20) 192 (156) 180 190 28 (23) 37 (30) 49 (40) 34 (28) 34 (28) 34 (28) 216 (175) 190 200 28 (23) 49 (40) 49 (40) 34 (28) 34 (28) 34 (28) 25 (20) 253 (205) 200 210 28 (23) 49 (40) 49 (40) 51 (41) 34 (28) 34 (28) 34 (28) 279 (226) 211 250 28 (23) 43 (35) 49 (40) 34 (28) 34 (28) 34 (28) 25 (20) 247 (200) To convert organic nitrogen to cows/ha divide number by 85 The recommendations in this table are for farms on soils of average natural fertility. At stocking rates less than 200 kg organic N/ha substantially more fertilizer N than is recommended in this table can be applied on poorer soils. Less than recommended fertilizer N is needed on soils with above average natural fertility or where there is plenty of clover in the sward. At very high stocking rates of greater than 200 kg organic N/ha slightly more fertilizer N (for example 8 kg/ha) than is presented in this Table can be applied in southern counties and this should be applied in spring as part of the first or later applications. 16
Fertilizer N for different stocking rates on the area available for grazing during the year. Rates of fertilizer N are presented in kg per ha (units per acre in brackets). Stocking rate Fertilizer N Stocking rate Fertilizer N Stocking rate Fertilizer N (cows/ha) kg/ha (u/ac.) (cows/ha) kg/ha (u/ac.) (cows/ha) kg/ha (u/ac.) Mid March Jan/Feb March May & June April May July & Aug June July August Sept <1.2 0 28 (23) <3.50 28 (23) 17 (14) <2.00 17 (14) 17 (14) 1.2 1.4 28 (23) 28 (23) 3.50 3.75 28 (23) 26 (21) 2.0 2.5 26 (21) 25 (20) 1.4 1.6 28 (23) 38 (30) 3.75 4.00 38 (30) 34 (28) 2.5 3.0 34 (28) 34 (28) 1.6 1.8 28 (23) 49 (40) 4.00 4.25 49 (40) 42 (35) 3.0 3.5 34 (28) 26 (21) 25 (20) >1.8 28 (23) 49 (40) >4.25 49 (40) 51 (41) >3.5 34 (28) 34 (28) 34 (28) The recommendations in this table are for farms on soils of average natural fertility. At stocking rates less than 200 kg organic N/ha substantially more fertilizer N than is recommended in this table can be applied on poorer soils. Less than recommended fertilizer N is needed on soils with above average natural fertility or where there is plenty of clover in the sward. At very high stocking rates of greater than 200 kg organic N/ha slightly more fertilizer N (for example 8 kg/ha) than is presented in this Table can be applied in southern counties and this should be applied in spring as part of the first or later applications. 17
Section 11 Step-by-Step Guide to Master the Grass Wedge 1. Write down date you are walking the farm on the farm walk recorder page 2. Estimate/measure the quantity of grass in the paddock and write down the paddock number in the square beside the value (on the farm walk recorder page). If two paddocks have the same value put the second paddocks number in the column to the right 3. When finished farm walk you will see that the paddocks are ranked from highest to lowest (on the farm walk recorder page) 4. Write the paddocks in this order on the manual Grass Wedge page to the right of Paddock No. / Name 5. Shade the squares up to the dry matter yield of the paddock On the manual grass wedge page: 6. Write in the stocking rate (cows/ha) on the grazing platform 7. Write in allocation per cow (see section 4) 18
8. Write in the rotation length (days) 9. Write in how much grass you want left in the paddock when it is grazed 10. Calculate target pre-grazing yield by multiplying stocking rate, allocation per cow and rotation length and then adding on post grazing residual 11. In the first column mark your target pre-grazing yield with an X (1,300 kg in the diagram) 12. In the last highlighted column mark your target residual with another X (100 kg in the diagram) 13. Draw a line from one X to the other Your wedge is complete time to make some decisions (Clearly from the example there is far too much grass on the farm and surpluses need to be removed see page 21 for appropriate actions to take in similar situations) 19
Section 12 Understanding your Grass Wedge The line on your wedge graph is drawn from the target pre-grazing yield (calculated using the equation below) to the target post-grazing residual. Target pre-grazing yield equation Stocking Rate (cows/ha) x Allocation (kg DM/cow/day) x Rotation length (days) + Residual (what will be left in the paddock after grazing) = Target pre-grazing yield (kg DM/ha) A perfect wedge is one where all the paddocks are meeting the line that is there are no surpluses (paddocks above the line) and no deficits (paddocks below the line), everything is on target. However, frequently this is not the case. The following sequence of graphs gives various scenarios that may arise and also outlines actions that should be taken to correct surpluses or deficits. 20
Surplus Wedge The following four graphs are examples of farms with surplus grass. There is a brief explanation underneath each graph, after the fourth graph there is a list of actions that can be taken if a surplus is encountered on the farm. Average Cover: 278 KgDMHa Average Growth: 94 KgDMHa/Day 2,350 2,300 2,250 2,200 2,150 2,100 2,050 2,000 1,950 1,900 1,850 1,800 1,750 1,700 1,650 1,600 1,550 1,500 1,450 1,400 1,350 1,300 1,250 1,200 1,150 1,100 1,050 1,000 950 900 850 800 750 700 650 600 550 500 450 400 350 300 250 200 150 100 50 0 3-7B 3-7A 7-1B 8-2A 7-1A 5-1A 5-1B 4-4B 2-2A 8-2B 1-2A 2-2B 4-4A COVER From the wedge above it is evident that this farmer has lost total control of the grass on the farm. Pre-grazing yields are too high and well above target, as are residuals. Decisions need to be made to rectify the problem. 21
Average Cover: 995 KgDMHa Average Growth: 95 KgDMHa/Day COVER 1,500 1,450 1,400 1,350 1,300 1,250 1,200 1,150 1,100 1,050 1,000 950 900 850 800 750 700 650 600 550 500 450 400 350 300 250 200 150 100 50 0 3-7B 3-7A 7-1B 8-6A 8-6A 2-6A 3-1B 4-1A 4-1B 2-6B 7-2A 3-1A 5-8B 5-8A In the wedge above although the paddocks with the highest covers are on target all the rest are above target. It is clear that there will be a large surplus on the farm in a week s time thus action needs to be taken to ensure target pre-grazing yield is not exceeded. In addition, it is clear that the target residual (post-grazing height) is not being achieved and this needs to be addressed or there will be sward quality issues in subsequent rotations. Average Cover: 917 KgDMHa Average Growth: 80 KgDMHa/Day COVER 2,500 2,450 2,400 2,350 2,300 2,250 2,200 2,150 2,100 2,050 2,000 1,950 1,900 1,850 1,800 1,750 1,700 1,650 1,600 1,550 1,500 1,450 1,400 1,350 1,300 1,250 1,200 1,150 1,100 1,050 1,000 950 900 850 800 750 700 650 600 550 500 450 400 350 300 250 200 150 100 50 0 7-8A 5-3B 3-6A 3-6B 2-9B 8-1B 2-9A 6-5B 4-3A 8-1A 4-3B 7-8B 1-3A 5-3A 6-5A 1-3B It is evident from the above wedge that grass is in surplus on the farm and will need to be addressed. When taking action the farmer should be mindful that some paddocks are below target and therefore all paddocks with surplus should not be removed. 22
COVER 1,400 1,350 1,300 1,250 1,200 1,150 1,100 1,050 1,000 950 900 850 800 750 700 650 600 550 500 450 400 350 300 250 200 150 100 50 0 Average Cover: 741 KgDMHa 4-1B 8-6B 8-6A 2-6B 3-1B 5-8B 7-2A 5-8A 3-1A 6-8B 6-8A 4-1A 8-1A 2-6A 7-2B Average Growth: 62 KgDMHa/Day The wedge above shows that there will be a surplus of grass in a few days. However, in this example target residuals are being achieved. Dealing with Surplus Grass Remove surplus paddocks as silage this should be completed as soon as possible (or when the paddock reaches 2,500 kg DM/ha) so that the paddocks will be back in the grazing rotation as quickly as possible. If the grass in the paddock is not too strong have other animals such as replacement heifers graze it. Caution should be exercised so that in situations, like the last graph, excessive grass is not removed resulting in a deficit. Removing surplus grass as soon as it is identified will result in the area being included in the grazing round and therefore making it available to cope with a slowing of pasture growth. 23
Deficit Wedge The next three graphs are examples of farms with deficits i.e., not enough grass available to meet target pre-grazing yields. There is a brief explanation below each graph, after the third graph we give a list of recommended actions that can be taken if a deficit is encountered on the farm. Average Cover: 421 KgDMHa Average Growth: 31 KgDMHa/Day COVER 1,500 1,450 1,400 1,350 1,300 1,250 1,200 1,150 1,100 1,050 1,000 950 900 850 800 750 700 650 600 550 500 450 400 350 300 250 200 150 100 50 0 6-5B 8-1A 8-1B 4-3A 4-3B 5-3A 1-3B 6-5A 3-6B 3-6A 1-3B 7-8B 2-9B 2-9A It is clear from this graph above that there is a serious deficit of grass on the farm. Extreme action needs to be taken to address the problem. 24
Average Cover: 736 KgDMHa Average Growth: 24 KgDMHa/Day 2,800 2,700 2,600 2,500 2,400 2,300 2,200 2,100 2,000 1,900 1,800 1,700 COVER 1,600 1,500 1,400 1,300 1,200 1,100 1,000 900 800 700 600 500 400 300 200 100 0 6-3B 7-4B 7-4A 3-5B 3-5A 2-7A 2-7B 4-9A 8-4B 5-4A 4-9B 1-6A 8-4A 5-4B In the graph above, although the first two paddocks are above target there may be a deficit in a week or two if growth rate remains low. Therefore, caution should be exercised and hasty decisions to remove surpluses should not be taken or if necessary the skipped over paddocks may be partly of totally grazed to fill any small deficit. 25
Average Cover: 759 KgDMHa Average Growth: 50 KgDMHa/Day COVER 2,000 1,950 1,900 1,850 1,800 1,750 1,700 1,650 1,600 1,550 1,500 1,450 1,400 1,350 1,300 1,250 1,200 1,150 1,100 1,050 1,000 950 900 850 800 750 700 650 600 550 500 450 400 350 300 250 200 150 100 50 0 1-8B 1-8A 3-1A 7-2B 8-6A 8-6B 2-6A 7-2A 6-8B 5-8A 4-1A 6-8A 5-8B 4-1B 3-1B 2-6B It can be difficult to make decisions when faced with the graph above. In this situation the next three paddocks to be grazed have a pre-grazing yield higher than the target (i.e., there is surplus grass) however, there is a deficit on the way. Again, quick decisions to remove surpluses should not be made. Dealing with a Deficit In all cases before magic day (day where grass growth equals grass demand) do not speed up the round After magic day consider increasing the grazing area/day during the deficit period if soil temperatures have continued to rise and pasture growth is increasing Supplement with concentrate or grass silage (preferably high quality baled silage that was previously removed as surplus as it will be of better quality than pit silage) Increase the grazing area if there are replacement heifers/beef cattle on the grazing platform remove them if possible 26
A Cold Snap or Soil Moisture Deficit Average Cover: 995 KgDMHa Average Growth: 95 KgDMHa/Day COVER 1,400 1,350 1,300 1,250 1,200 1,150 1,100 1,050 1,000 950 900 850 800 750 700 650 600 550 500 450 400 350 300 250 200 150 100 50 0 7-7B 2-BB 2-8A 4-2B 8-6A 1-4B 5-7A 1-4A 4-2A 7-7A B-3B 3-8B B-3A 3-9A The above graph is a good example of what occurs during a period of heavy frosts and low soil temperatures, or during a period of soil moisture deficit. The last paddock was grazed well below the target residual, which will also impact on subsequent re-growth rate. Although this farm has plenty of grass for the next 10 days the farmer should be mindful that a deficit may be on the way and remedial action may be necessary before this occurs. If temperatures rise or if it rains the deficit may be short lived. The key action to consider here is completing another farm walk during the week, i.e. walk the farm twice during the week. 27
Wet Weather Average Cover: 995 KgDMHa Average Growth: 95 KgDMHa/Day COVER 1,400 1,350 1,300 1,250 1,200 1,150 1,100 1,050 1,000 950 900 850 800 750 700 650 600 550 500 450 400 350 300 250 200 150 100 50 0 7-7B 1-4B 5-7A 1-4A 7-7A 4-2A 6-6B 3-9B 3-9A 4-2B 2-8B 2-8A A wedge, such as the one above, results when a period of very heavy rainfall is encountered and target residuals can not be achieved. Consequently, sward quality will deteriorate in subsequent rotations. To prevent cows grazing poorer quality swards these paddocks could be grazed off and topped when the weather improves or they could be closed for silage, depending on the time of year. 28
Adequate Grass Supply but at Different Levels Initially it may appear that there is a surplus or deficit however when the graphs are examined it is clear there is sufficient grass on the farm. Average Cover: 995 KgDMHa Average Growth: 95 KgDMHa/Day COVER 1,500 1,450 1,400 1,350 1,300 1,250 1,200 1,150 1,100 1,050 1,000 950 900 850 800 750 700 650 600 550 500 450 400 350 300 250 200 150 100 50 0 7-4A 3-5B 3-5A 2-7A 2-7B 4-9A 4-9B 8-4A 5-4A 9-4B 7-4B 5-4B 1-6A 6-3A It is clear from this graph that there is surplus grass in the first three paddocks but there is a deficit on the way. On balance there is sufficient grass on this farm and no action needs to be taken. Target residuals must be achieved on the paddocks with surplus grass. This will slow down the grazing round and give more time for the paddocks below the target line to catch up. 29
Average Cover: 741 KgDMHa Average Growth: 62 KgDMHa/Day COVER 1,400 1,350 1,300 1,250 1,200 1,150 1,100 1,050 1,000 950 900 850 800 750 700 650 600 550 500 450 400 350 300 250 200 150 100 50 0 4-1B 8-6B 8-6A 2-6B 3-1B 5-8B 7-2A 5-8A 3-1A 6-8B 6-8A 4-1A 8-1A 2-6A 7-2B This graph shows a situation where the paddocks due to be grazed next are not at target pre-grazing yield. However, there is sufficient grass on the rest of the farm. No action needs to be taken in this situation. Average Cover: 995 KgDMHa Average Growth: 95 KgDMHa/Day COVER 1,400 1,350 1,300 1,250 1,200 1,150 1,100 1,050 1,000 950 900 850 800 750 700 650 600 550 500 450 400 350 300 250 200 150 100 50 0 7-4B 7-4A 3-5A 3-5A 5-4B 2-7A 2-7B 4-9B 5-4A 1-6B 4-9A 8-4A In the graph above it appears that there is a deficit, however, the last four paddocks have sufficient grass. If there is a low stocking rate on the farm there should be sufficient grass and no action needs to be taken. 30
Average Cover: 741 KgDMHa Average Growth: 62 KgDMHa/Day COVER 1,550 1,500 1,450 1,400 1,350 1,300 1,250 1,200 1,150 1,100 1,050 1,000 950 900 850 800 750 700 650 600 550 500 450 400 350 300 250 200 150 100 50 0 7-1A 6-9A 8-2A 4-4B 5-1A 5-1B 1-2B 8-2B 2-2A 1-2A 4-4A 2-2B 7-1B 2-6A 3-7B In the graph above the first two paddocks are at target pre-grazing yield, the next three paddocks are in deficit and all paddocks after this are at or above target. Consequently, there is sufficient grass on the farm and no action needs to be taken. 31
Example: Farm Walk Recorder DATE: Available kg DM/ha 2500 Paddock Number/Name 2400 2300 2200 2100 2000 1900 1800 1700 1600 1500 1400 1300 1200 5 1100 1000 4 900 1 800 700 600 6 500 400 300 200 3 7 100 0 2 Instructions: Write the paddock name or number in the first empty column next to the available cover that you have measured/estimated is on the paddock. The above table has ranked the paddocks in order of the highest cover to the lowest pasture cover. Plot this information on the Grass Wedge page. 32
Example: Manual Grass Wedge DATE Available kg DM/ha 2500 2400 2300 2200 2100 2000 1900 1800 1700 1600 1500 1400 1300 1200 1100 1000 900 800 700 600 500 400 300 200 100 0 Paddock Number/ 5 4 1 6 3 7 2 Name The target line is drawn between the target pre-grazing yied and the target residuaie Use the following formula to calculate the pre-grazing yield required Stocking Rate x Allocation/Cow x Rotation + Residual = Target Pre-Grazing Yield 4 16 20 100 1380 cows/grazing ha kgdm/ha/day days kgdm/ha kgdm/ha Mark an x in the first column at the target cover Mark an x in the first column at the target pre-grazing yield Shaded area represents ideal target pre-grazing yield (1100 to 1500 kg DM/ha increase stocking rate if pre-grazing yield is too low) Mark an at the residual amount in the column of the Mark another x in paddock the last with column the at shortest the target cover residual Join the Join two the x s two points with a with straight a straight line line = Average Farm Cover (Calculated from the farm cover sheet) = Growth Rate 33
Example: Calculating a Farm Cover Paddock No. / Paddock DM yield Multiply by Paddock area Total Cover Name (kg DM/ha) (ha) (A) (kg DM) (B) 1 900 X 2.1 = 1890 2 100 X 2.5 = 250 3 200 X 1.9 = 380 4 1000 X 2.3 = 2300 5 1200 X 2.0 = 2400 6 600 X 1.8 = 1080 7 200 X 2.2 = 440 Sum column A and column B 14.8 8740 (A) (B) Divide column B (total cover) by A (area) [B A] 591 kg DM/ha (Farm Cover) To calculate the quantity of grass per cow 591 4 = 148 Farm cover Stocking rate = Cover per cow (kg DM/cow) Decisions for the coming week: 34
Farm Walk Recorder DATE: Available kg DM/ha Paddock Number/Name 2500 2400 2300 2200 2100 2000 1900 1800 1700 1600 1500 1400 1300 1200 1100 1000 900 800 700 600 500 400 300 200 100 0 Instructions: Write the paddock name or number in the first empty column next to the available cover that you have measured/estimated is on the paddock. When completed, the above table has ranked the paddocks in order of the highest cover to the lowest pasture cover. Plot this information on the Grass Wedge page. 35
Farm Walk Recorder DATE: Available kg DM/ha Paddock Number/Name 2500 2400 2300 2200 2100 2000 1900 1800 1700 1600 1500 1400 1300 1200 1100 1000 900 800 700 600 500 400 300 200 100 0 Instructions: Write the paddock name or number in the first empty column next to the available cover that you have measured/estimated is on the paddock. When completed, the above table has ranked the paddocks in order of the highest cover to the lowest pasture cover. Plot this information on the Grass Wedge page. 36
Farm Walk Recorder DATE: Available kg DM/ha Paddock Number/Name 2500 2400 2300 2200 2100 2000 1900 1800 1700 1600 1500 1400 1300 1200 1100 1000 900 800 700 600 500 400 300 200 100 0 Instructions: Write the paddock name or number in the first empty column next to the available cover that you have measured/estimated is on the paddock. When completed, the above table has ranked the paddocks in order of the highest cover to the lowest pasture cover. Plot this information on the Grass Wedge page. 37
Farm Walk Recorder DATE: Available kg DM/ha Paddock Number/Name 2500 2400 2300 2200 2100 2000 1900 1800 1700 1600 1500 1400 1300 1200 1100 1000 900 800 700 600 500 400 300 200 100 0 Instructions: Write the paddock name or number in the first empty column next to the available cover that you have measured/estimated is on the paddock. When completed, the above table has ranked the paddocks in order of the highest cover to the lowest pasture cover. Plot this information on the Grass Wedge page. 38
Farm Walk Recorder DATE: Available kg DM/ha Paddock Number/Name 2500 2400 2300 2200 2100 2000 1900 1800 1700 1600 1500 1400 1300 1200 1100 1000 900 800 700 600 500 400 300 200 100 0 Instructions: Write the paddock name or number in the first empty column next to the available cover that you have measured/estimated is on the paddock. When completed, the above table has ranked the paddocks in order of the highest cover to the lowest pasture cover. Plot this information on the Grass Wedge page. 39
Manual Grass Wedge DATE Available kg DM/ha 2500 2400 2300 2200 2100 2000 1900 1800 1700 1600 1500 1400 1300 1200 1100 1000 900 800 700 600 500 400 300 200 100 0 Paddock Number/ Name The target line is drawn between the target pre-grazing yield and the target residual Use the following formula to calculate the pre-grazing yield required Stocking Rate x Allocation/Cow x Rotation + Residual = Target Pre-Grazing Yield cows/grazing ha kgdm/ha/day days kgdm/ha kgdm/ha Mark an x Mark in the an first x column in the first at the column target at pre-grazing the target cover yield Shaded area represents ideal target pre-grazing yield (1100 to 1500 kg DM/ha increase stocking rate if pre-grazing yield is too low) Mark another Mark an x in at the the last residual column amount at the in target the column residual of the paddock with the shortest cover Join the two x s with a straight line Join the two points with a straight line = Average Farm Cover (Calculated from the farm cover sheet) = Growth Rate
Calculating a Farm Cover Paddock No. / Paddock DM yield Multiply by Paddock area Total Cover Name (kg DM/ha) (ha) (A) (kg DM) (B) Sum column A and column B Divide column B (total cover) by A (area) [B A] (A) (B) kg DM/ha (Farm Cover) To calculate the quantity of grass per cow = Farm cover Stocking rate = Cover per cow (kg DM/cow) Decisions for the coming week:
Manual Grass Wedge DATE Available kg DM/ha 2500 2400 2300 2200 2100 2000 1900 1800 1700 1600 1500 1400 1300 1200 1100 1000 900 800 700 600 500 400 300 200 100 0 Paddock Number/ Name The target line is drawn between the target pre-grazing yield and the target residual Use the following formula to calculate the pre-grazing yield required Stocking Rate x Allocation/Cow x Rotation + Residual = Target Pre-Grazing Yield cows/grazing ha kgdm/ha/day days kgdm/ha kgdm/ha Mark an x Mark in the an first x column in the first at the column target at pre-grazing the target cover yield Shaded area represents ideal target pre-grazing yield (1100 to 1500 kg DM/ha increase stocking rate if pre-grazing yield is too low) Mark another Mark an x in at the the last residual column amount at the in target the column residual of the paddock with the shortest cover Join the two x s with a straight line Join the two points with a straight line = Average Farm Cover (Calculated from the farm cover sheet) = Growth Rate
Calculating a Farm Cover Paddock No. / Paddock DM yield Multiply by Paddock area Total Cover Name (kg DM/ha) (ha) (A) (kg DM) (B) Sum column A and column B Divide column B (total cover) by A (area) [B A] (A) (B) kg DM/ha (Farm Cover) To calculate the quantity of grass per cow = Farm cover Stocking rate = Cover per cow (kg DM/cow) Decisions for the coming week:
Manual Grass Wedge DATE Available kg DM/ha 2500 2400 2300 2200 2100 2000 1900 1800 1700 1600 1500 1400 1300 1200 1100 1000 900 800 700 600 500 400 300 200 100 0 Paddock Number/ Name The target line is drawn between the target pre-grazing yield and the target residual Use the following formula to calculate the pre-grazing yield required Stocking Rate x Allocation/Cow x Rotation + Residual = Target Pre-Grazing Yield cows/grazing ha kgdm/ha/day days kgdm/ha kgdm/ha Mark an x Mark in the an first x column in the first at the column target at pre-grazing the target cover yield Shaded area represents ideal target pre-grazing yield (1100 to 1500 kg DM/ha increase stocking rate if pre-grazing yield is too low) Mark another Mark an x in at the the last residual column amount at the in target the column residual of the paddock with the shortest cover Join the two x s with a straight line Join the two points with a straight line = Average Farm Cover (Calculated from the farm cover sheet) = Growth Rate
Calculating a Farm Cover Paddock No. / Paddock DM yield Multiply by Paddock area Total Cover Name (kg DM/ha) (ha) (A) (kg DM) (B) Sum column A and column B Divide column B (total cover) by A (area) [B A] (A) (B) kg DM/ha (Farm Cover) To calculate the quantity of grass per cow = Farm cover Stocking rate = Cover per cow (kg DM/cow) Decisions for the coming week:
Manual Grass Wedge DATE Available kg DM/ha 2500 2400 2300 2200 2100 2000 1900 1800 1700 1600 1500 1400 1300 1200 1100 1000 900 800 700 600 500 400 300 200 100 0 Paddock Number/ Name The target line is drawn between the target pre-grazing yield and the target residual Use the following formula to calculate the pre-grazing yield required Stocking Rate x Allocation/Cow x Rotation + Residual = Target Pre-Grazing Yield cows/grazing ha kgdm/ha/day days kgdm/ha kgdm/ha Mark an x Mark in the an first x column in the first at the column target at pre-grazing the target cover yield Shaded area represents ideal target pre-grazing yield (1100 to 1500 kg DM/ha increase stocking rate if pre-grazing yield is too low) Mark another Mark an x in at the the last residual column amount at the in target the column residual of the paddock with the shortest cover Join the two x s with a straight line Join the two points with a straight line = Average Farm Cover (Calculated from the farm cover sheet) = Growth Rate
Calculating a Farm Cover Paddock No. / Paddock DM yield Multiply by Paddock area Total Cover Name (kg DM/ha) (ha) (A) (kg DM) (B) Sum column A and column B Divide column B (total cover) by A (area) [B A] (A) (B) kg DM/ha (Farm Cover) To calculate the quantity of grass per cow = Farm cover Stocking rate = Cover per cow (kg DM/cow) Decisions for the coming week:
Manual Grass Wedge DATE Available kg DM/ha 2500 2400 2300 2200 2100 2000 1900 1800 1700 1600 1500 1400 1300 1200 1100 1000 900 800 700 600 500 400 300 200 100 0 Paddock Number/ Name The target line is drawn between the target pre-grazing yield and the target residual Use the following formula to calculate the pre-grazing yield required Stocking Rate x Allocation/Cow x Rotation + Residual = Target Pre-Grazing Yield cows/grazing ha kgdm/ha/day days kgdm/ha kgdm/ha Mark an x Mark in the an first x column in the first at the column target at pre-grazing the target cover yield Shaded area represents ideal target pre-grazing yield (1100 to 1500 kg DM/ha increase stocking rate if pre-grazing yield is too low) Mark another Mark an x in at the the last residual column amount at the in target the column residual of the paddock with the shortest cover Join the two x s with a straight line Join the two points with a straight line = Average Farm Cover (Calculated from the farm cover sheet) = Growth Rate
Calculating a Farm Cover Paddock No. / Paddock DM yield Multiply by Paddock area Total Cover Name (kg DM/ha) (ha) (A) (kg DM) (B) Sum column A and column B Divide column B (total cover) by A (area) [B A] (A) (B) kg DM/ha (Farm Cover) To calculate the quantity of grass per cow = Farm cover Stocking rate = Cover per cow (kg DM/cow) Decisions for the coming week:
NOTES
NOTES
NOTES
www.farmersjournal.ie CashCows Dairy EditorJackKennedy sguidetomilkingmoremoneyfromgrass Jack Kennedy s Dairy DVD Cash Cows, Jack Kennedy s guide to milking more money from grass Farmers Journal Dairy Editor Jack Kennedy tours Ireland visiting dairy farmers involved in high-profit milk production. Grassland Management Milking Parlours Calving Calf Rearing Forage Crops Price: 25 Call 01 4199505 to purchase today or send a cheque with your name and address to Dairy DVD, Irish Farmers Journal, Irish Farm Centre, Bluebell, Dublin 12 View promotional clip on www.farmersjournal.ie today
Published by Teagasc Dairy Production Research Centre Moorepark Fermoy County Cork t: 025 42222 www.teagasc.ie Irish Farmers Journal Irish Farm Centre, Bluebell, Dublin 12 t: 01 4199500 www.farmersjournal.ie