The drone is becoming to agriculture what the smartphone is to the Internet. High payoff uses are increasingly self-evident, especially mapping, image and sensor health diagnostics, and spraying. Drones are the core of precision agriculture (PA), the term that captures the essence of their value.
The basic focus of PA is surveying crops and gathering data. Drones that meet this basic need start around $1,500. Most farmers are choosing fixed wing, rather than multi-rotary for improved battery life, higher payload and the ability to carry multiple sensors. Prices for full function systems cluster in the $15-25,000 range. This is obviously unaffordable for very small growers, but low-end drones offer mapping and diagnostic capabilities for a low outlay. Drone services are rapidly emerging, averaging $1,000 a day. (Versus $10,000 for a helicopter.)
Here is a fairly standard case example of “agdrones” in action, in Ji County, Shanxi, China apple tree pesticide spraying: 10 minutes per orchard versus 2 ½ hours using manual labor. Smallholder 60 years old, now runs farm by himself, saving of $145 per acre. Describes drones as a “Godsend.”
Here are representative reported benefits:
- Infra-red plant diagnostics: signs of plant stress are apparent through sensors ten days before the physical damage is visible.
- Satellite and aircraft imaging: halves the costs for farms smaller than 20 hectares. Satellites revisit areas every 1-3 days, affected by weather, image resolution in meters. Drones resolution in centimeters, oblique angle images, variable heights.
- Spraying: water savings of up to 90%, chemicals reduced 30-50%.
- Productivity: five times faster than tractor application of pesticides.
- Planting: decrease in costs of 85%
- Irrigation, health assessment: hyperspectral, thermal, and multispectral sensors identify field areas of dryness, heat signatures, vegetation index of density, and growth, bacterial and fungal infections.
There are obviously barriers to the take up of PA licensing, regulation, subsidies, insurance, and pilot training/certification are examples. In general, though, governments are encouraging drone use. Japan is the leader, mainly because its labor costs and shortages are so high. US fruit farmers and vineyards are investing in large-scale drones. China is moving fast. India has been hampered by the lack of credit facilities for small farmers, but a study of impacts in Tamil Nadu state reported rice and fruit crop yield increases of 20-80%. Tea seems to be lagging and fragmented, but major projects are underway in Sri Lanka, Taiwan, and parts of Africa.