Marginal Gains Theory - How to destroy the "because it's cheap" approach in agriculture

I learned early on in my career that "that's what we've always done" could be a gigantic blocker to change in viticulture. Fortunately, and unfortunately at times, that's not how I was raised and not how I was trained as a viticulturist in the early years of my career. In general, I find a lot of joy in testing systems to see if they can be done better, faster, cheaper; this is not with the ultimate goal of necessarily spending less no matter what, but having more freedom to pivot within the budget. As much joy as this approach has brought, it has, at times, brought so much frustration when it's been met with the "if it ain't broke, don't fix it" response.

A similar iteration of this same mentality has plagued many as the price of farming continues to rise. Because it's cheap. By no means is this a problem unique to just agriculture, but I simply find it a poor excuse and it does my head in. So, feeling inspired after visiting the Banksy exhibit in Wellington last month, I felt equipped to finish this blog. Because it's about time we...

"Think outside the box, collapse the box, and take a fucking sharp knife to it"

-Banksy

Marginal Gains Theory

If you’ve never heard of marginal gains theory, please google it for some great reading.

The basic principle is that small improvements can have a compounding effect that leads to sustainable and significant gains over time. This is the horse I’m betting on to get our industry through this rough period, not AI, not robotics, not some magic new cultivar.

So how is this taking a knife to the box, and what even is the box?

The box I see is assuming we are already at best practice, and we need to find an automated solution which will be our saviour:

• Robots for pruning

• Unmanned tractors

• Robots for yield estimates

• Disease resistant varieties

The problem with this is at it's roots these tools are being developed to replace current practice, skipping the assessment of whether current practice is actually best practice. Can we spray less if we have disease resistant varieties, yea probably, but is there an opportunity to spray less in our current systems? I believe so.

The Low Hanging Fruit

To keep this as short as possible we'll keep this as a pros and cons list with some indication of contribution to gains over time.

Rounds of unnecessary mowing

Pros

• Less compaction

• More flowering plants

• More inter-row diversity

• Less diesel use

• Less tractor hours

• More potential carbon sequestration

• Potential benefits to beneficial insects

Cons

• Too much growth can interrupt labour tasks

• Unknowns (e.g. humidity, competition, frost risk, etc.)

• Compromised spray coverage IF interow growth gets between the sprayer and the canopy

Gains

• Direct cost savings

Rounds of unnecessary spraying - check the blog

Pros

• Less compaction

• Less diesel use

• Less tractor hours

• Less "off target" exposure

• Less wasted chemicals

• More efficient use of staffing

• Potential benefits to beneficial insects

Cons

• Unknowns (disease risk - where flag shoots present)

Gains

• Direct cost savings

Rounds of unnecessary irrigation

Pros

• Fewer trimming passes

• Less under vine weed growth potential

• Less lateral growth

• Potential yield control tool (location specific)

• Cost savings (e.g. electricity from pumping or water use)

• Less nutrient leaching

• More water in rivers/aquifers

Cons

• Weak areas may get excessively stressed

• Fewer opportunities to catch leaks

Gains

• Direct cost savings

• Better ecosystem management (more water in the system and less leaching)

Overlooked Opportunities

It's easy to overlook some items with less direct cost savings/gains. These often include spending money to "make" money.

Cultural Practices - Head Thinning

Pros

• Better airflow & sun exposure in the head

• Fewer pruning cuts in the head

• Better winter pruning options (potentially cheaper pruning cost)

• Greater fruitfulness potential

• Better/more effiecient nutrient useage

Cons

• In season cost

Gains

• Fewer pruning wounds = lower trunk disease potential

• Better disease control

• Indirect cost savings/money (cheaper pruning potential, and increase yield potential)

Cultural Practices - Early Leaf Plucking

Pros

• Better airflow & sun exposure

• Better spray penetration

• Potentially lower yields

• Greater production of phenolic precursurs

• More time to acclimate to sun exposure

Cons

• Potentially lower yields

Gains

• Better disease control

• Indirect cost savings (better microclimate in the fruit zone = reduced disease pressure = potential to extend spray interval)

Cultural Practices - Concentration based spraying

DEMONSTRATION PURPOSES ONLY DON'T USE AS DOSAGE GUIDE - Ingredients: Each 5ml contains paracetamol 250mg

This one needs a bit of a blurb first, and the best example to use is sulphur, as everyone uses it. Label rates are getting better, but still often have rates per area (lbs/ac or kg/ha) - and sulphur is one that people still use this way.

By concentration spraying, we're looking at the efficacy of the solution you apply regardless of area. As water rates increase over the course of the season to cover the growing canopy, the solution that controls disease does not generally have to change. I liken it to children's tylenol/pamol - as my kid grows, I give him more volume of medicine, from the same bottle.

You can work back from your later season sulphur applications to determine what concentration works best for you. For example, if late in the season 4kg/ha sulphur works to control powdery mildew, when arguably the pressure is the highest, the kg/L or lbs/gal you're mixing in the tank should easily control powdery mildew in the early season. You're spraying the same solution, just less volume because there is less tissue to cover.

Pros

• Easier tank mixing instructions

• Lower chemical use

• Less money

• Less off target exposure

Cons

• Cannot think of any

Gains

• Direct cost saving

• More sustainable

• Less carbon footprint from chemical purchases

Cultural Practices - Mechanical Crop Thinning

Pros

• Removes trash from the bunches

• More cost effective

• Quicker pass

• Reduces disease risk

• Better spray penetration into bunches

Cons

• Requires mechanical harvester availability

• Timing more critical than hand thinning

• May still have bunch overlap

Gains

• Potential cost savings on thinning pass

• Better disease control per bunch

Cultural Practices - Cross Arms

Pros

• Better canopy microclimate

• More sun exposure to buds = greater fruitfulness potential

• Dappled light on fruit and interior leaves

• Lower wire lifting costs

• Less potential for mowers and mulchers to pick up untidy dropped wires

Cons

• Installation cost

• Floppy growth habit vines are not ideal

• Narrow rows may not be suitable

Gains

• Better canopy architecture for VSP vines

• Better spray penetration

• Potentially lower costs by fewer lifting passes

Abstract Opportunities

Within the realm of gains out there, I see some missed opportunities in the tech that is being tested and developed as well. This goes back to the tools in development now looking at robotics and AI. Having heard the pitches and sometimes included in the the process of using the tech, people developing these tools are looking at the major pain points. How can we use this tech to solve major problems in the vineyard (i.e. yield estimation and pruning)? As a long term strategy, this is absolutely the right track, but what seems to be lacking is assessments of what practical tools could we develop along the way. I'll give two away, but there are more for sure.

Robotic Irrigation Monitoring

While people are spending millions to develop yield estimate algorithms off the cameras driving around the vineyard, I wish them luck, having managed vineyards myself there is a small, simple and costly job that irrigated vineyards could benefit from while still developing the other tech.

Imagine if the cameras counting your vines and bunches, were also hooked up with an infrared camera (or simpler) that was aimed at the drip line, which could pick up on breaks, clogged emitters, broken Ts, etc. Evaporative cooling around breaks and drippers vs hot lines where no water is running. Simple and saves hours of labour driving around looking for this broken line.

Disease Risk Assessment based on Canopy Growth

I've seen tools that identify yellow spots and flag these as potential disease hot spots, but I have yet, not to say it's not out there, to see a camera based system that flags rate of shoot growth as a risk assessment tool for spray programs.

I am not against calendar spray programs because I think they always spray too much. I am against them because intervals should not be based solely on the chemistry's label interval. People must consider unprotected tissue. If the temps are cool and your canopy has not grown in addition to temperatures that are not favourable to disease growth - stretch your window a bit. However, if the temperatures are warm, and the vine has plenty of resource for rapid growth, your vines may have significant amounts of unprotected tissue in prime disease conditions well before your normal interval - you might want to shrink your interval. Imagine if your cameras and dashboards gave you a risk index based on shoot growth captured while driving around.

Now's the Time to Chat

We need to spend more time thinking outside the box, if not taking that knife to it, and less time living in the blue sky space. Flashy tech with an expensive price tag, and not taking advantage of the small gains does not mean you are setting yourself up to farm better, you're just adding a new tool inside the box.

Please - comment if you agree or disagree - we learn by talking to each other and growing together.