Ripping midrows. Solving Soil Compaction.
What Happens to Vineyard Soil Compaction — and How Quickly Does It Come Back?
Soil compaction is one of the less visible consequences of vineyard machinery traffic, but it can have a significant effect on the way water, oxygen and vine roots move through the soil profile.
Every pass of a tractor, sprayer, harvester or truck applies pressure to the soil. Over time, repeated traffic can increase bulk density, reduce pore space, decrease infiltration and increase soil penetration resistance. In a vineyard, this can restrict root exploration and concentrate the vine’s root system into a smaller volume of soil.
One response is to rip the mid-row — using a deep-ripping or subsoiling implement to fracture compacted layers.
But ripping is not necessarily a permanent solution.
The important question is not simply “Does ripping reduce compaction?”. It is “How long will that reduction in compaction remain?”
What does mid-row ripping actually do?
Deep ripping uses a narrow tine, often fitted with wings or a foot, to travel below the compacted layer and mechanically fracture the soil.
Unlike conventional cultivation, the objective is not necessarily to turn the soil over. Instead, the tine creates a network of fractures and fissures through the compacted layer.
This can:
reduce penetration resistance
increase macroporosity
improve water infiltration
increase the volume of soil available to roots
improve aeration
provide pathways for water movement
allow roots to penetrate previously restrictive layers.
Australian soil-management guidance identifies deep ripping as an effective method for removing subsurface compaction, particularly where a distinct compacted layer has been identified.
However, the result depends heavily on soil moisture at the time of ripping.
Moisture is critical
A ripper does not automatically “break up” compacted soil simply because it is pulled through it.
The soil needs to be in a condition where it fractures rather than smears.
If a heavy clay soil is too wet, the tine can pass through the profile while deforming and smearing the soil rather than creating the desired network of cracks.
Research on vineyard soils in southern France demonstrated this very clearly. Deep tillage produced substantially more soil compaction when performed under wet conditions, while ripping caused less structural degradation than deep ploughing.
Australian guidance similarly recommends ripping when the soil is sufficiently dry or friable to fracture rather than smear.
This is particularly important in heavier vineyard soils.
The objective isn’t to rip as deep as possible. It is to rip deeply enough to fracture the compacted layer under the right moisture conditions.
What happens to bulk density?
One of the simplest ways of measuring compaction is bulk density.
Bulk density is essentially the mass of dry soil per unit volume. As soil becomes compacted, particles are pushed closer together and the volume of pore space decreases, so bulk density increases.
Ripping can temporarily reverse this process by creating additional pore space.
Research from the University of Adelaide examining vineyard soil management found that deep ripping could substantially increase the volume of low-resistance soil available for vine roots where a genuine compacted layer existed. At Padthaway Range, ripping approximately doubled the volume of low-resistance soil.
But the same research also demonstrates an important point:
the response is highly site-specific.
If the soil does not have a significant mechanical restriction, ripping may produce little meaningful benefit.
This is why ripping should ideally follow a soil-profile investigation, rather than being undertaken simply because a vineyard has been in production for a certain number of years.
Vine roots respond to soil strength
For grapevines, the important issue isn’t necessarily bulk density itself.
What the vine experiences is mechanical resistance to root penetration.
As soil strength increases, root elongation becomes increasingly difficult. Research into vineyard soil management has shown that high soil strength can restrict root growth, limiting the volume of soil available to the vine for accessing water and nutrients.
A compacted layer can therefore effectively create an underground barrier.
The vine may have adequate water and nutrients in the soil profile, but its roots may not be able to exploit that volume effectively.
This is particularly important in dryland or water-limited vineyards, where deep rooting can provide access to stored soil water later in the season.
But how quickly does the soil become compacted again?
This is where ripping becomes particularly interesting.
It is tempting to think of ripping as:
Compacted soil → rip it → loose soil → problem solved.
In reality, it is closer to:
Compacted soil → rip it → temporarily loosened soil → machinery traffic + natural settling → progressive recompaction.
And the process can begin surprisingly quickly.
Recompaction can occur within a single season
Australian soil-management research has documented recompaction under wheel tracks within one year of deep ripping in a heavy clay soil. The original extent of compaction had returned within approximately four years following deep ripping.
That doesn’t mean every vineyard will follow a four-year cycle.
Soil texture, moisture, axle load, tyre pressure, traffic frequency and traffic location all influence the outcome.
But it demonstrates an important principle:
Deep ripping does not permanently remove the forces responsible for compaction.
If machinery continues travelling across the loosened soil, the same mechanical forces that created the original compacted layer are simply being reapplied.
The first wheel pass matters
One of the most important findings from soil-compaction research is that compaction is not linear with the number of passes.
The first pass can cause a disproportionately large amount of structural damage.
Australian soil-health guidance cites research showing that the first vehicle pass over wet soil can cause around 90% of the eventual compaction damage.
More recent field research has also demonstrated that repeated wheeling increases soil structural deformation, with traction particularly increasing the severity of compaction.
This has an important implication for vineyards.
If a mid-row has just been ripped and a tractor subsequently drives directly along the freshly loosened soil, the benefit of ripping can be substantially reduced.
It doesn’t necessarily require dozens of passes.
A small number of heavy passes under the wrong soil-moisture conditions can undo a considerable amount of the work.
Soil moisture determines how rapidly recompaction occurs
The risk is greatest when the soil is moist enough to deform under load.
Dry soil generally has greater bearing strength and resistance to deformation.
Wet soil has much less resistance to the stresses imposed by machinery, particularly when the soil is near field capacity or wetter.
This is why trafficking a vineyard following rain can be considerably more damaging than trafficking the same vineyard when the soil has dried sufficiently.
The relationship between moisture, axle load and compaction is well established in soil physics research. Subsoil compaction is particularly likely when heavy axle loads are applied to moist soil, and deep subsoil compaction can be extremely persistent.
For vineyards, this creates a difficult management conflict:
The soil condition that is best for root growth and water infiltration isn’t necessarily the condition that is safest for driving heavy machinery across the vineyard.
Vineyards are particularly exposed to traffic compaction
Unlike many annual cropping systems, vineyards can receive machinery traffic for decades.
Spraying, mowing, fertilising, undervine management, harvesting and transport can result in hundreds of machinery passes over the life of a vineyard.
Research specifically examining vineyards has demonstrated increased soil compaction associated with machinery traffic. Studies in Croatian vineyards found differences in soil resistance and bulk density between trafficked inter-row areas and less-compacted areas, while research in southern France demonstrated both topsoil and subsoil compaction associated with tractor traffic.
A study of machinery systems in vineyards also found that heavier conventional tractor/implement combinations generated greater compaction, while larger tyre contact areas could reduce average pressure on the soil despite greater machine mass.
This highlights an important point:
Machine weight is important, but it isn’t the only variable.
Compaction is influenced by:
axle load
tyre inflation pressure
tyre contact area
soil moisture
number of passes
wheel slip and traction
traffic location
soil texture
existing soil structure.
So should you rip the mid-row?
Not automatically.
Deep ripping makes the most sense when there is evidence of a genuine physical restriction.
Before ripping, dig a soil pit or use a suitable soil penetrometer to establish:
Where the compacted layer occurs.
How deep it extends.
Whether it is continuous.
Whether vine roots are being restricted.
Whether the restriction is caused by machinery or is a natural soil horizon.
Whether the soil chemistry — for example sodicity — is contributing to the problem.
This is particularly important because mechanical ripping cannot necessarily solve a chemical soil constraint.
For example, if sodicity is causing clay dispersion and structural collapse, simply ripping the soil may create temporary physical space without addressing the underlying cause.
The GRDC/Soil Science Australia guidance therefore emphasises identifying the soil constraint before deciding on deep ripping and notes that other constraints such as sodicity, acidity and water repellence can limit the response.
The biggest mistake: ripping and then driving over it
Perhaps the most important management principle is simple:
Don’t spend money loosening soil and then immediately compact it again.
After ripping, machinery traffic should be minimised over the freshly loosened zone wherever practical.
This is where controlled traffic becomes particularly valuable.
If tractors can repeatedly travel along the same wheel tracks, the compacted area is effectively concentrated into a relatively small proportion of the vineyard.
The remaining soil can stay relatively undisturbed.
Research and Australian soil-management guidance consistently identify controlled traffic as a means of extending the benefits of deep ripping by reducing subsequent recompaction.
In a vineyard, this can mean deliberately establishing permanent traffic lanes rather than allowing machinery to move randomly across the mid-row.
How long should the benefit of ripping last?
There isn’t one universal answer.
Depending on the soil and management system, the effect may last:
months → several years → considerably longer.
Some research has reported very rapid recompaction, while other soils retain benefits for several years. A review of deep ripping research notes that sandy soils can often recompact within around three years, while the duration of benefits varies considerably between soils and management systems.
In heavy clay soils, Australian research has documented evidence of recompaction within a year and substantial return toward the previous compacted condition within four years.
Conversely, if machinery traffic is controlled, the benefit can potentially persist considerably longer.
The critical distinction is therefore not simply “How long does ripping last?”
It is:
“How long does ripping last under the traffic and soil-moisture conditions of this vineyard?”
Ripping should be viewed as part of a soil-management system
Ripping is a mechanical intervention, not a complete soil-management strategy.
The most durable approach combines:
Identify → rip → protect → monitor.
Identify
Measure soil penetration resistance, bulk density, soil structure and root distribution to establish whether compaction actually exists.
Rip
Rip only the affected layer and only when the soil is at a moisture content that allows effective fracturing.
Protect
Minimise subsequent traffic, particularly when the soil is wet. Use controlled traffic wherever practical.
Monitor
Return to the same locations and measure soil resistance, bulk density and root development over time.
This is much more informative than simply deciding that a vineyard should be ripped every three or four years.
The vineyard takeaway
Mid-row ripping can be an effective way of mechanically relieving a compacted soil layer and increasing the volume of soil that vine roots can explore.
But the benefit is not permanent.
Machinery traffic begins rebuilding soil compaction as soon as significant loads are applied to the loosened soil. Under favourable conditions the soil may remain relatively open for years; under wet conditions and repeated heavy traffic, significant recompaction can occur within a single season and potentially after only a small number of passes.
For vineyards, therefore, the real objective shouldn’t be:
“Rip the vineyard every few years.”
It should be:
“Identify the compacted layer, rip it correctly, and then manage traffic so that the soil isn’t compacted again.”
A well-timed ripping operation followed by controlled machinery traffic can potentially provide a much longer-lasting improvement than repeated ripping without traffic management.
And perhaps most importantly, don’t rip simply because the vineyard is old. Establish that compaction is actually limiting the soil first. Research from vineyards in Australia and overseas shows that the response to ripping is highly site-specific, and where significant compaction is absent, the benefits can be limited.
References
Håkansson, I., & Reeder, R.C. (1994). Subsoil compaction by vehicles with high axle load—extent, persistence and crop response. Soil & Tillage Research, 29, 277–304.
Alakukku, L. (1999). Subsoil compaction due to wheel traffic. Agricultural and Food Science, 8, 333–351.
van Dijck, S.J.E., & van Asch, T.W.J. (2002). Compaction of loamy soils due to tractor traffic in vineyards and orchards and its effect on infiltration in southern France. Soil & Tillage Research, 63, 141–153.
Coulouma, G. et al. (2006). Effect of deep tillage for vineyard establishment on soil structure: A case study in Southern France. Soil & Tillage Research, 88, 132–143.
Bogunović, I. et al. (2016). Soil compaction in vineyards of different ages
in Pannonian Croatia. Journal of Central European Agriculture, 17(2).
ten Damme, L. et al. (2021). Soil structure response to field traffic: Effects of traction and repeated wheeling. Soil & Tillage Research, 213, 105128.
Hamza, M.A. & Anderson, W.K. (2005). Soil compaction in cropping systems: A review of the nature, causes and possible solutions. Soil & Tillage Research, 82, 121–145. The associated Australian research demonstrates the importance of traffic management following deep ripping.
Hansen, D.W. (2005). Impact of vineyard soil management on soil physical properties and vine response. University of Adelaide thesis, including trials of deep ripping in South Australian vineyards.
Macdonald, L. et al. (2021). Deep ripping: Correcting layers of high soil strength with deep tillage – Southern region. GRDC/Soil Science Australia.
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