Up until the 1970's or in some cases the 1980's blackcurrants were picked by hand into buckets which were then transferred into trays in the field, loaded onto pallets and then onto open sided lorries. Handpicking a large acreage (some growers even then were harvesting between 50 and 100 acres) was challenging – at around 100 buckets per tonne and 3 tonnes per acre equating to 15,000 – 20,000 buckets – a logistical nightmare for 1200 disorganised casual workers. As plantations expanded and the picking community declined in the countryside mechanical harvesters were developed.
The first harvesters, notably the Bruff Static Picking Machine and the Bruff-Appleton Harvester were archaic compared with those available today but started to save labour and ease the harvesting job. The Static Picking Machine was used on the plantation headland, where it was operated by a small gang, who fed in branches that were passed on from another team who had cut fruiting wood from the plantation. After stripping the fruit from the wood the fruit passed onto a wide belt where it was checked for quality before being weighed up in trays. Although this machine was useful in the respect that pruning was carried out whilst harvesting, it couldn't perform a very complete job.
Soon the Static Machine was used in conjunction with the Bruff Appleton Harvester which was a tractor mounted harvester designed to pick the fruit after the static machine had selectively pruned and harvested those older branches. This machine moved through the bushes where steel plucker fingers removed the fruit from the bushes often with significant amount of leaf and twig. Whilst this was a significant improvement on the rigours of handpicking it did not generate a particularly good fruit sample or help the bush through to the next season.
Straddle Harvesters - Pattenden, Smallford, Somerset Fruit and Joonas
During the 1980's the above companies developed straddle harvesters which were usually self propelled with two wheels each side of the bush and with the frame and driver about 8 foot above the ground immediately above the bush. The operator drove the machine so that the bush was divided centrally and scooped into the central body of the machine where shaker fingers vibrated the fruit from the bush. As these fingers shake at up to 2000 rpm the ripened fruit drops onto conveyor belts below where it was carried to upwards where fans blew of leaves and disgorged at the back into trays. There would be two trailers at the back, one each side of the bush, where two operators would prepare trays, check the fruit for quality and stack trays until the trailer was full and ready to be loaded onto pallets and then again onto the lorries.
Two important factors apply in respect of fruit harvested by straddle machines. Firstly, the machine is incapable of differentiating between fruit at varying stages of ripeness and therefore the sample may not be acceptable for some of our customers; and secondly, harvesters must be operated by highly capable and trained operators as the growers cannot afford to lose time in delays and breakdowns. Both of these affect the percentage of crop recovered and its acceptability to the buyer. However, the fruit picked by straddle harvesters contains little or no strig compared with hand picked fruit. Quality controllers at the back of the machines work hard to ensure any sticks or foreign bodies are removed. We rarely harvest in wet weather - wet fruit does not travel well and is unsuitable for freezing or storing.
Straddle harvesters are still widely used and have been further developed through the last 20 years to continuously improve performance, minimise bush damage and incorporating health and safety requirements. Many of the models also now use cross conveyors to move the fruit into a third row so that stoppage time is minimised as the tractors rotate. The fruit is also usually picked into large ½ tonne bins which makes transport significantly easier. A modern machine is usually operated in daylight hours only and depending on the hours worked can pick up to 50 tonnes in a day using only an operator, 2 quality controllers and 2 tractor drivers – a far cry from the crowds of handpickers of the 1960's and 1970's.
There are problems associated with modern harvesters such as the dust that can be created by the machine and which may settle on the fruit still to be picked, making it unsuitable for harvesting. This problem is exacerbated by cross alleyways and the headlands in the plantation especially if the grass is not well established. Care must be take to place the filled bins where they will not be contaminated by dust and dirt.
Routine general maintenance must be carried out regularly during the harvesting season including pressure washing when there is an opportunity. Most growers now have on-farm workshops and can perform most maintenance without referring to manufacturer.