Estimating our cherry harvest though our census

In 2021 we ran a data experiment to see how effective we were in estimating the total size of our harvest in January 2022.

We randomly selected 150 trees in the orchard using a small random coordinate generator program that we wrote. We then tagged each of these trees with a number so that our staff could regularly collect data about them throughout the year

We then counted the number of fruit buds on each tree, the number of flowers, and finally the number of fruitlets and cherries to actively estimate the size of our harvest in January.

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Top - Fruit buds in winter, Fruit spurs (only photo we have is from Autumn hence the yellowing leaves), Full Bloom

Bottom - Early fruitlets, unripe cherries after many fruitlets naturally shredded, quality cherries ready for harvest

At each of these stages, we could estimate the size of our first harvest off our 3 year old and 2 year old trees. You can see the results in the table below. Please note this is a harvest on very young trees, which yielded probably 2-3% of what we expect at full production in 2026.

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*assumption made that the average cherry weighed ±10 grams when picked.

You will note that our first and last estimate for each variety was accurate, but our estimate at blossom time was considerably higher. We ended up with a much higher flower count than anticipated and unfortunately a few factors meant we were unable to take full advantage of this.

• Rain: 52mm of rain fell between December 1st and 27th, and a further 16mm of rain fell before the 31st. This led to fruit cracking due to excessive water uptake through the tree roots, and water caught in the bowl (where the stem joins the cherry) and sitting there. Both types of cracking render the fruit unfit for consumption.
  
• Insects: earwigs had an impact on our crop, largely due to our under-tree weed control not being as effective as it needs to be. Earwigs take a bite from a cherry, rendering it worthless.
  
• Birds: We had around a dozen birds, mostly Tauhou (Silvereye) and Redpolls trapped inside our orchard, nets who enjoyed pecking at our fruit. We scared many of them out, but unfortunately we still had some bird damage to our crop.

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Our census data is being used in wider research into pollination

One of the great things about leading zero fossil fuel food production in New Zealand is that you get to partner with some truly awesome people and in this case Abacus Bio collected their own data on pollination over the same 150 random trees.

Pollination happened over a two-week period at the end of September and the start of October. Taylors Pass Honey provided the beehives; 20 in total and Abacus Bio conducted research during this time, with daily visits to our "census trees" from their researchers, counting and photographing flowers and  bee activity. The long-term aim is for the pollination period to be as short and early as possible and their report will make for interesting reading.

If you have read to this point you will know how important it was for us to prove that this concept can be a reality. Without a doubt we have proven that you can produce export quality cherries without using a single drop of fossil fuel. With our partners and experts around us, we are working hard to grow this capacity and resilience. We know that next season our trees will be taller, our harvest will be 10-15 times as large, and there will be many more complications to conquer.  

Our first census of 2022 has us sitting at 30 tonnes of cherries!

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