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MUSHROOM HARVESTING
AUTOMATION Donal Gernon, specialist mushroom adviser with Teagasc, explores the advances currently being made in the field of mushroom production automation
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ike other horticultural enterprises, commercial mushroom production is highly labour intensive. Labour accounts for onethird of a mushroom growers overall cost of production. Mushroom growers face the constant challenge of recruiting and retaining staff to harvest their crops. The current method of harvesting mushrooms consists of one-handed picking, manually cutting the mushroom stalk, placing the mushroom into the punnet, weighing the punnet to ensure it reaches the correct weight specification, labelling the punnet, and placing the punnet into the crate. This has been the standard process since mushroom production began. However, as the availability of skilled labour evaporates, the industry must look at streamlining the process to maximise harvesting efficiency. On the current conventional mushroom farm, the average pick rate is between 25-30 Kilograms of mushrooms per hour. This pick rate is achieved by adopting basic harvesting principles such as graze picking and separation. Pick rate can vary from farm to farm depending on size specification per product and product mix. Over the past two decades, many growers have been forced to close their mushroom enterprise due to difficulties found in recruiting and retaining staff to harvest their crops.
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Unfortunately, unless mushroom harvesting automation is developed and adopted, this trend is set to continue. Due to the sensitivity of the mushroom, designing a robot to aid in harvesting is a very difficult task. The emphasis from mushroom engineering companies currently focuses on designing semi-automated systems that will increase harvester productivity by introducing twohanded picking. Various concepts have been designed and implemented with positive results on farms all over the world. Some of these designs can be implemented into the existing mushroom tunnel structures and some technologies require investment in new buildings and infrastructure.
TILTING SHELVES The tilting shelf system is a method whereby a standard shelf is divided into two sections that tilt towards the harvester at a 45-degree angle. This makes it much easier for the harvester to see the current crop and to harvest the correct mushroom. The tilting shelf eliminates the strain of reaching across the mushroom bed to harvest mushrooms, which in turn speeds up the picking process. The shelves are only tilted during harvesting and they return to the horizontal position once picking has ceased. A mushroom conveyor runs alongside the shelves, the harvester places the mushroom
MAIN PHOTO; CONVENTIONAL DUTCH SHELVING SYSTEM; TOP RIGHT: SINGLE LAYER SYSTEM; BOTTOM RIGHT: STANDARD IRISH MUSHROOM CROP.
into designated slots and the conveyor transports these mushrooms out into the central corridor, where the mushrooms are placed in punnets.
DRAWER SYSTEM The drawer system is a system whereby a farm is designed so that crops are winched from one growing room to another during the harvest period. A picking station is located in the central corridor and the crop is pulled to the harvester. This is in comparison to the conventional picking system where harvesters move through the crop within the tunnel. The crop can be pulled across from one growing room to another several times a day to allow the harvester to easily graze pick and thus maximise mushroom size and yield. The two big advantages to this system are that the harvester only needs to focus on one area and it is visually much easier to identify and pick the correct mushroom as there is no crop directly above the shelf.
SINGLE LAYER The single-layer system involves crops being grown in specific growing rooms up until mushrooms are ready to be harvested. They are then winched into the harvesting room. In the growing room, the crops are stacked
HORTICULTURECONNECTED / www.horticultureconnected.ie / Autumn/Winter 2021
