Heat-stress index for olive trees

The problem

Olives are Jordan's most important tree crop, yet they're watered by the calendar and habit rather than the tree's actual need. Farmers only notice a tree's thirst after symptoms appear, when part of the crop is already lost. A soil sensor measures the soil, not the tree: the soil may hold water while the root can't absorb it because of salinity or heat, giving a reassuring but misleading reading.

How it works

1. MeasurementAn infrared sensor measures the leaf surface temperature without contact.
2. Reference readingAir temperature, humidity, and solar radiation are read at the same moment.
3. Calculating the indexThe difference between leaf and air temperature is turned into a stress index calibrated on the orchard.
4. BaselineThe index is compared with a baseline built from well-watered trees.
5. DecisionStressed trees are marked on the map with watering priorities.
6. SendingReadings are sent wirelessly over long distances to the farm or the phone.

Project features

• The system measures the tree itself, not the soil, so the index reflects the plant's real condition.
• The index is based on an internationally recognized agricultural basis, not an assumed threshold.
• Measurement is contactless, so it doesn't harm the leaf and can read dozens of trees quickly.
• A baseline is built for each orchard, so the index is calibrated on that orchard's own trees, not a generic value.
• A solar-powered node that transmits over long distances, so it works in fields without power or networks.

Expected challenges

These are the main obstacles to expect during the build, laid out clearly so you know them before you start.

• The index is affected by wind, solar radiation, and humidity; without compensating for them, readings contradict each other.
• Timing is decisive: the correct reading is taken at a specific hour around noon.
• Calibrating an orchard needs a baseline from well-watered trees and thirsty ones.
• The sensor reads the average temperature of an area, not a single point, so distance and angle affect the value.
• Real validation of the results takes a full season, while the defense shows how readings correlate over two weeks.

The consultation gives you a solution for each one.