In 2020, King’s College Cambridge broke with tradition and left a large area of lawn unmown. This area grew into a beautiful meadow, and was cut and baled that August by traditional methods using two shire horses.
The biodiversity of this meadow has been allowed to develop in subsequent years, and now includes a wide variety of plants and flowers – recently a count of 84 different plant varieties was reported, of which only 33 had been sown. Further research on the meadow, comparing it with the neighbouring lawn, suggested that approximately three times more species of plants, insects and spiders were present in the meadow than on the lawn. Furthermore, bats were feeding over the meadow far more frequently than over the lawn. Given this is such a small area of land – the meadow being approximately half a football pitch in size, these results over such a short period of time are striking.
With my Agritech head on, I am not at all surprised by the increase in biodiversity, as farmers for many years have realised that keeping hedgerows and wild flower margins can increase pollination rates in their fields. However, the speed and extent of the change is impressive.
There were also significant additional environmental benefits from the meadow beyond increased biodiversity. First of all, the meadow reflects more sunlight than the lawn, whereby the soil temperature (and thus the localized environment’s temperature) was lower. Second, there was no requirement to water or fertilise the ground within the meadow – it required little if any maintenance. On the other hand, the lawn needed to be watered during dry periods, and occasionally it would be fertilized or otherwise maintained during the year to keep it healthy. Also, the absence of regular mowing reduced ground compaction and the amount of carbon emissions over the land.
These kinds of benefits are increasingly being exploited in the agricultural sector. For example, grants can be secured for putting land down to permanent grassland. As a consequence, growing hay rather than monoculture crops is a viable option for many farmers for at least a part of their farmland. Grants can also be secured for leaving wide margins or flowering crops around the fields, or for planting or laying hedges. These all increase biodiversity and will lead to increased pollination rates across the rest of the farm due to the increase in the number of pollinators. Indeed, many farms additionally utilise this by having beehives nearby to provide further homes for the pollinators.
In addition to the increased pollination, many farms have found that such complementary margins can have significant pest-control benefits. A clear example of this is in respect of oil seed rape crops, which can be rapidly destroyed by an infestation of cabbage stem flea beetles. Many of the known insecticides that are still available to farmers, such as certain pyrethroids, although effective on some crops, are becoming increasingly ineffective at controlling such beetles on oil seed rape crops, as the cabbage stem flea beetles have developed a resistance to some of these insecticides. However, there are numerous natural predators for the beetles, including parasitic wasps such as Tersilochus microgaster, which parasitises beetle larvae in the spring, and Microctonus brassicae, which instead attack the adult stage of the beetle. The use of these margins, together with the reduction in insecticide use, can allow these natural predators to survive and thrive on such beetles, thus controlling their numbers and allowing the oil seed rape to develop properly.
Minimal tillage can also have a complementary benefit as many larvae of these beneficial parasites will overwinter in the soil in their pupal, and heavy tillage, and particularly ploughing, can damage or kill the pupae.
Agritech companies are also seeking to reduce the amount of ground interaction, and in particular ground compaction, occurring across a farm. One solution is the use of wider equipment – often with wider booms, so that fewer tracks are needed across a field. This will reduce the overall percentage of compacted ground in a field. Other approaches utilise larger numbers of smaller vehicles – particularly in the robotic space where the vehicles can operate for longer hours due to not requiring an operator on site. Being lighter, each vehicle causes less ground compaction. Another approach is fewer ground interactions, for example no-plough or minimal till and direct drilling options. These disturb the ground less and can improve carbon retention in the ground. This area of development also includes reducing the amount of plant interactions, for example by using localised or topical interactions rather than whole-field interactions. Various sprayer manufacturers, such as those by Knight Farm Machinery Ltd from Oakham, offer tractor mounted sprayers with a 30m wide folding boom, or trailed or self-propelled sprayers with 40m booms, each with GPS section switching. These machines allow both a wide section of a field to be treated in a single pass and more localised application of its spray to the plants or sections of the field that need it, rather than a whole-field approach. They can also use spray nozzles designed to reduce the hang-time of the spray in the air, along with automatic boom levelling mechanisms, to keep the nozzles close to the plants, thus reducing wind drift of the spray.
Many of these solutions require good data for controlling the equipment. This is often local data acquired by the farmer or by contractors. For example, drone or tractor mounted cameras can be used to secure the data on the crops as they grow, which can be used in real time or for later use, such as with GPS systems. Drones in particular can capture the data with no ground interaction, and allow a crop’s condition to be analysed before even entering the field. This can be for numerous forms of agriculture, including grain crops, brassicas and fruits, amongst others. For example, Outfield, based in Cambridge, has developed a platform that takes drone footage of a crop – usually a fruit orchard, and uses machine learning to create tree maps and plant status data, such as blossom densities, so that the correct amount of spray can be automatically provided to each tree by a sprayer.
With these wide ranging changes and developments to the agricultural sector, it is unlikely that farmers will revert wholeheartedly to the approaches of the past, such as shire horses and chemical free farming. However, there is certainly a trend towards reducing chemical use, especially given the cost benefit of doing so, alongside an increasing use of complementary margins and natural pest-control methods. If a farmer’s time can be saved by utilising these more natural techniques, then perhaps they will have more time and money to enjoy those traditional pastimes, thus keeping them going for many years to come!
