Climate Actions for November

• Review your parasite control plan for liver fluke
• Order your protected urea for 2023
• Test your silage
• Soil sample your farm
• Continue to spread lime where conditions allow
• On low K Index soils, apply 50% Muriate of Potash when closing up paddocks

Review your parasite control plan for liver fluke going into the housing period

The economic losses associated with stomach worms and liver fluke in cattle are universally accepted. The image of cattle clinically affected with liver fluke and worms is embedded in the mindset of beef and dairy farmers and their veterinary practitioners.

However, the scouring or coughing animal with severe weight loss and maybe ‘bottle jaw’ is only the ‘tip of the iceberg’. The sub-clinical component of parasitic infection, with its potential impact on growth rate, milk yield and fertility lies ‘beneath the surface.’ Poor productivity in sub-clinical worm and liver fluke infections is mainly due to reduced appetite and feed intake. Once these effects are appreciated, it is easy to see why cattle cannot perform to their full potential when they are infested with parasites. In addition, there are other reasons for productivity losses caused by worms, including poor digestion and absorption of nutrients and these can further complicate the effects of reduced feed intake.

Losses due to parasites are often assumed rather than measured. Nevertheless, anecdotal evidence from farmers, advisors, veterinary practitioners, regional veterinary laboratories and veterinary researchers points to apparently increasing problems with parasites. Appropriate use of anthelmintics is a key consideration in sustainable control of parasites. Therefore, these drugs must be used carefully in order to benefit both animals and farmers. Because of differences in susceptibility resulting from acquired immunity to worms, it is best to consider cattle in three different age categories: adults, second grazing season (SGS) and first grazing season (FGS). 

Read more here A Guide to Parasite Control at Housing - AHI pdf

Order your protected urea for 2023

Every tonne of protected urea contributes to reducing GHG emissions in the national inventory.

Why use protected urea?

1. Protected urea consistently and reliably produces top yields under Spring and summer grazing conditions
2. Protected urea has lower nitrous oxide emissions compated to CAN and lower ammonia compared to urea
3. It is substantially cheaper than CAN on a cost per unit of nitrogen basis. Buying 5 tonnes of CAN is the equivalent of buying 3 tonnes of protected urea because of the higher nitrogen content of protected urea.  And at today’s prices for CAN and protected urea, buying the 3 tonnes of protected urea instead of 5 tonne of CAN, you will save you €1,000. Therefore, if you use 20 tonne of CAN in any one year, switching to buying 12 tonne of protected urea, instead of 20 tonne of CAN, will save you €4,000. 
4. There are no residue issues with protected urea

Read more here Protected Urea pdf

Test your silage and match concentrate feeding rate to the quality of the silage

Taking a representative silage sample

• Poor sampling technique is one of the main causes of unreliable silage analysis results.
• Wait 5-6 weeks after ensiling to take the samples
• Ideally use a long core sampler to sample 3-5 points from well spaced points on or between diagonals on the pit surface as per diagram. Core to within 0.5m of the pit floor
• Alternatively sample an open pit by taking 9 grab samples in a ‘W’ pattern across the pit face. Where high performance diets are being fed (e.g. finishing cattle, fresh milking cows) it is advisable to repeat sample at 4- week intervals if using this method
• Discard the top 100mm of each core before mixing into a composite sample.The final sample should weigh approximately 500g.
• Exclude air, seal well and post immediately. Avoid posting samples late in the week

A standard silage sample from 500-tonne pit represents about 0.0001% of fresh material available– ensure that a standard procedure is followed to generate representative samples

For further details on interpreting your silage analysis, read page 26 Quality Grass Silage for Dairy & Beef Production Systems pdf

Soil sample your farm

The results of a soil analysis are only as good as the sample on which it is based. To give reliable advice, a soil sample must be representative of the area sampled and be taken to a uniform depth (10cm).

The principle of soil analysis is to determine the average nutrient status of an area and to give a measure of the available nutrients in the soil. A sample normally consists of 0.25 – 0.5 kg of soil and this is taken to represent the entire sampling area or field.

1. To take a soil sample it is essential to have a suitable soil corer
2. Ensure soil cores are taken to the correct sampling depth of 100 mm (4”)
3. Take a soil sample every 2 to 4 ha. (5-10 acres)
4. Take separate samples from areas that are different in soil type, previous cropping history, slope, drainage or persistent poor yields
5. Avoid any unusual spots such as old fences, ditches, drinking troughs, dung or urine patches or where fertiliser / manures or lime has been heaped or spilled in the past.
6. Do not sample a field until 3 to 6 months after the last application of P and K and 2 years where lime was applied.
7. Take a minimum of 20 soil cores, mix them together, and take a representative sub-sample for analysis, making sure the soil sample box is full.
8. Take a representative soil sample by walking in a W shaped pattern across the sampling area.
9. Sample fields at the same time of the year to aid comparisons of soil sample results and avoid sampling under extremes of soil conditions e.g. waterlogged or very dry soils.
10. Place the soil sample in a soil box to avoid contamination and write the field number and advisor code on the soil box with a black permanent marker.

Soil Sampling Pattern

Continue to spread lime where conditions allow

Now is the ideal time to apply lime to correct soil pH on mineral soils.  Lime will bring many benefits from increasing the availability of soil nutrients (N, P, K & S) to improving soil structure (aeration & drainage).  Soils maintained at a soil pH 6.3 to 6.5 will release up to 70kg N/ha/year from soil organic N reserves.  This will help reduce chemical fertiliser nitrogen (N) bills on farms by approximately €70/ha/year.  Lime will increase the availability of soil phosphorus (P) and is the first step to improving / building soil P levels cost effectively.  Maintaining the optimum soil pH will in addition increase the response to applied N, P & K in either organic manures such as cattle slurry / FYM and N, or bag fertilisers such as 10-10-20 / 18-6-12 etc…. 

Over the coming days / weeks check soil test results and apply lime to fields based on lime recommendations.  Target fields with the lowest soil pH first and apply lime where the opportunity presents for example after grazing paddocks, 2^nd / 3^rd cut grass silage or at reseeding time.  Soils maintained at the optimum soil pH 6.3 will grow approximately 10 to 15% extra grass during the growing season.  Ground limestone is the cheapest and most cost effective tool to control soil acidity in the long term.  Apply a maximum of 7.5t/ha (3t/ac) ground limestone in a single application.   

On low K Index soils, apply 50% Murate of Potash when closing up paddocks 

Potassium (K) has a major role in the efficient use of nitrogen (N) by the grass plant during the growing season.  Grass silage crops have the largest demand for N & K during the growing season for example a typical 1st cut will require 100 to 125kg K/ha while grazing fields require 15 to 30kg K/ha.  Maintaining good soil K levels in silage fields is essential to grow high yields of quality grass silage annually.  Now is the ideal time to think about the grass silage crop for 2021 and apply additional K to build and replenish soil K levels.

In 2020 there has been multi cuts of grass silage taken to fill winter feed requirements.  Each 1 ton dry matter/ha (~2 ton fresh grass /ac) removes 25kg K/ha (20 units/ac). For example 2 cuts of grass can remove in the region of 200 to 250kg K /ha (160 to 200 units K /ac) depending on grass yield (8 to 9t DM/ha or 16 to 18 t fresh grass/ac). Therefore to determine K removals calculate grass silage yields and aim return sufficient K to replenish soil K reserves each year. 

Over the last number weeks grass growth rates have been extremely high due to the good grass growing conditions, a proportion of this grass has been taken out as high quality bale silage.  It is important to apply K on these areas of the farm to replenish K removed in bale silage. For example 4 bales/ac of grass silage will remove approximately 6 units P & 40 units K/ac.

Potassium can be supplied all year round (no restriction like N & P) as fertiliser K (Muriate of Potash 50% K).  Muriate of potash (MOP 50% K) can be applied at any time of the year and is an effective way to build soil K levels rapidly. Plus it simplifies the fertiliser programme reduces the risk/ issues with grass tetany in the spring time.

Where cattle slurry has been applied make adjustments for K based on slurry quality (DM%) see table 1 below.

Now is the ideal time to check soil test results and identify which fields (Index 1 or 2) that require additional K to build soil fertility to the agronomic optimum Index 3. Aim to apply recommended rates of K as shown in table 2 below over the coming weeks.