Pasture Productivity Following Pugging

The effects of pugging extend beyond reduced pasture growth. Pugging breaks up soil aggregates and damages large soil pores, leading to increased bulk density and compaction. These changes in soil physical properties further exacerbate the negative impact on pasture growth⁴ and water infiltration. 

Key Points:

• Pugging, caused by cows' hooves sinking into wet soil, can lead to soil compaction and reduced pasture growth. 

• Medium to heavy pugging during winter can result in a 40-42% reduction in spring pasture yield and a 34-40% reduction in pasture utilisation. 
  This can lead to losses of 2,000 - 4,000 kg DM/ha in spring, impacting the value of the pasture. 

Strategies to mitigate against pugging include: 

• Deep-rooted plant species like tall fescue can restore soil structure and increase nutrient availability. Densely tillered perennial ryegrass cultivars may also provide improved support. 

• Proper grazing management, such as avoiding waterlogged paddocks and increasing pasture covers, can mitigate pugging damage. 

• Utilizing sacrifice paddocks or feed pads during high-risk periods can reduce the impact on the milking platform. 

If you have issues with pugging: 

• Assess the density of pugged pastures to determine the extent of damage and plan for renovation. 

• Recommended recovery strategies depend on the level of plant density loss: rest and recovery for less than 20% loss, rolling and overseeding for 20-40% loss, cultivation and reseeding for 40-60%+ loss. 

• Renovation techniques include oversowing, reseeding, cultivation, rolling, and rest and recovery. 

• Variety and species options depend on the timeframe until full renovation is required and the specific sub-category. 

• Consult with a Barenbrug representative or local agronomist for guidance in choosing the best course of action. 

The Impact on Pasture Growth  

Research conducted in south-western Victoria, assessing perennial ryegrass, revealed that medium to heavy pugging during winter resulted in a 40-42% reduction in pasture yield that spring. Additionally, pasture utilisation was reduced by 34-40%¹ of feed on offer (FOO).   

The impact of 40% reduction in pasture yield, during spring alone can equate to losses of 2,000 - 4,000 kg DM/ha, equating to a value of $650 - $1,300/ha using Dairy Australia FVI values of approximately 30c/kg DM in Spring⁸. It is therefore important that pugged pastures are assessed, and damage rectified if wanting to maximise pasture growth in spring and in subsequent lifespan of the pasture.  

In Season Management  

To mitigate against the issue of pugging and promote pasture recovery, various management strategies can be adopted.  

Species and Variety Selection  

In extremely prone areas, implementing practices that can enhance organic matter content, and promoting the growth of deep-rooted plant species, can help restore soil structure and increase nutrient availability for pasture growth^3,6. Species like tall fescue are more suited to wet waterlogged soils then ryegrass and therefore can provide greater resilience against pugging. In addition, due to the deeper root structure they can also draw down further on soil moisture profile in summer & autumn leading into the high-risk winter & spring months. Fortune tall fescue is a suitable option as well given its better winter production over other continental tall fescue varieties. Likewise, more densely tillered diploid perennial ryegrass cultivars, such as Rohan NEA2 or Maxsyn NEA4, may provide improved support over a tetraploid cultivar.  

Grazing Management  

Furthermore, proper grazing management plays a crucial role in mitigating the impact of pugging. Avoiding grazing waterlogged paddocks during periods of high soil moisture can prevent serious pugging damage to pastures and soils. This is especially important in wet weather conditions, such as winter and early spring⁶. Often farmers will increase the grazing area and daily break to reduce the stocking rate intensity that can exacerbate the damage. Likewise, increasing pasture covers prior to grazing, back fencing grazed areas and shorter grazing durations (on-off grazing) can assist with reducing the impact. On-off grazing reduces the time cows are searching for feed, after the initial grazing when pasture mass is higher.  

Sacrificing Paddocks or Utilising Feed Pads  

During periods of likely pugging events, it is recommended to utilise sacrifice paddocks or feed pads instead of damaging all the paddocks. This practice helps reduce the impact on the milking platform. Although damage periods can be prolonged depending on the year, the high-risk times are relatively short. By removing stock from the milking platform, pasture density can be maintained until it is suitable for grazing again, helping maximise production and reduce impact of pugging.  

In summary, the impact of pugging on pasture growth in a dairy system can be substantial. It reduces yield, pasture utilisation, and negatively affects soil structure. However, by implementing strategies farmers can mitigate the effects of pugging and promote pasture recovery. If however you do have pugged pastures, below provides some guidelines to getting those pastures producing again.  

 Assessing Pasture Damage  

What to do if you have pugged pastures?

After pugging, it is crucial to assess the density of the pasture to determine the extent of damage and plan for renovation. Pasture density refers to the number of desirable plants per unit area, which directly impacts forage production and quality. 

Assessment	Recommended Strategies
< 20% loss in plant density	Rest and recovery and potentially rolling, apply fertiliser and lets plants retiller / recover
20-40% loss in plant density	Rolling and overseeding is a suitable solution to increase density.  Overseeding options should depend on the current species and the expected timeframe before reseeding would have occurred.
40-60% + loss in plant density, limited compaction	Rolling and overseeding may be an option. Determine how long you would be considering before renovation occurs. If a relatively new pasture, look for a longer term over-sowing option. Full cultivation and reseeding of pasture of summer crop an option if required soon anyway.
40-60% + loss in plant density, compaction and water pooling	Cultivation of some description required in order to aerate soil, reduce compaction and establish pasture. A summer crop following this cultivation may be a suitable option

Renovation and Overseeing Strategies 

When it comes to renovating pugged pastures, there are several methods that can be employed. Here are some renovation techniques commonly used: 

Strategy	Detail
Oversowing	This method involves direct drilling new grass seed over the damaged areas to encourage regrowth and fill in gaps. It can be effective for light to moderate pugging.
Reseeding	In more severe cases of pugging, reseeding the entire paddock may be necessary. This involves removing the existing vegetation and sowing new seed to establish a fresh pasture. This may involve direct drilling or cultivation techniques.
Cultivation	Harrowing or cultivating the pugged areas can help break up compacted soil and promote better drainage and reduce compaction. It also helps to incorporate the seed into the soil for improved germination. This should be employed when damage is moderate to severe and where re-seeding is occurring.
Rolling	Rolling is a common strategy used to address pugged pastures. Rolling can help to smoothen and level the soil surface, improve seed-to-soil contact, and promote better pasture establishment.
Rest and recovery	In minor damage cases, allowing the pugged pastures time to rest and recover can be beneficial. Temporary fencing can be used to keep livestock off damaged areas, giving them a chance to regenerate naturally.

Solutions

What are the variety and species options I should consider dependent on the scenario?

Once you have decided on the best course of action, based on the tables above, you need to decide the best variety or species option. Below is an outline of  

Strategy	Timeframe Until Full Renovation Required	Suitable Options
Overseeding	1 year	Renovator SR; Tempo Italian ryegrass; Hogan annual ryegrass
	2-3 years	Renovator Elite; Samurye NEA12 & Shogun NEA2 hybrid ryegrass
	4 years +	Renovator Elite; Maxsyn NEA4, Array NEA2 & Rohan NEA2 perennial ryegrass

Strategy	Sub-Category	Suitable Options
Re-seeding	Poorer fertility, background weeds	Summer Crop to 1) fill summer feed gap and 2) alleviate any issues before establishing perennial pasture.   Commander chicory: Late summer & autumn feed, multiple graze; 8-to-10-week establishment; 21-to-28-day rotation.   Falcon leafy turnip; 6-8 weeks to maturity, multiple graze (2-3)  Leafmore forage rape: 8-10 weeks to maturity, multiple graze  Dynamo turnip: 12-14 weeks to maturity, single graze
	Improved fertility, little background weed issues	Renovator 850i; Maxsyn NEA4, Array NEA2 or Rohan NEA2 perennial ryegrass; combination of Rohan (tiller density) with either Array or Maxsyn.
	Extremely prone area to pugging	Consider a deep-rooted perennial option such as Fortune tall fescue; avoid grazing in winter months.

Whilst these tables above provided some suggested options, there are many scenarios to consider. It is advisable, if unsure to consult with a Barenbrug representative or your local agronomist.  

Sources: 

¹ Impact of pugging by dairy cows on pastures and indicators of pugging damage to pasture soil in south-western Victoria - ResearchGate  

² On-off grazing to prevent pugging | Managing wet soils - Agriculture Victoria  

³ Soil Structure – Pugging - NDDT New Zealand  

⁴ Managing Cattle Impacts When Grazing on Wet Soils - Colorado State University Extension  

⁵ Soil management for dairy and beef cattle grazing - NSW Department of Primary Industries  

⁶ Managing Pastures in Wet Weather, Spring & Summer - Dairy Australia