Issue link: https://read.dmtmag.com/i/401644
34 NOVEMBER 2014 GOOD FRUIT GROWER www.goodfruit.com an extra "red edge" band between red and near infrared in the electromagnetic spectrum, which helps to quan- tify leaf chlorophyll content and potential nitrogen defi- ciencies. RapidEye imagery can cover a large area with a five-meter pixel resolution and can revisit daily. Brown expects that there will be a move away from using satellite imagery toward using ATV- and drone- mounted sensors. LIDAR: This is remote-sensing technology, normally used from an aircraft. It measures distance by illumi- nating the target with a laser and measuring how far the beam goes down and bounces back up. The name comes from a combination of "light" and "radar." It generates high-resolution images, including contour and three-di- mensional maps. It is often used in forests to make 3-D images of the canopy to assess biomass. It is also used to measure erosion and landscape evolution, where gullies are forming, for example. TERRESTRIAL LASER SCANNING: The Lidar technology can now be used on the ground, rather than in the air, which brings the accuracy of the 3-D images down to one millimeter. That's a sharp enough resolution to see veins on a leaf. The laser device can be oriented horizontally or vertically and could be put on a platform or post, or driven through the orchard. Brown sees potential for this to be used to map fruit on the trees. "The fruit would jump out because they have a very different shape from the leaves," he said. TERRAIN MODELING: Open-source software is avail- able that can generate insolation maps, showing how much sun exposure and solar energy each part of the farm receives. It is based on digital elevation and slope gradi- ent maps along with calculations of the angle of the sun combined with the angle of the ground surface. Brown thinks this could be valuable information for orchards and vineyards, particularly relating to fruit maturity. It can also detect low areas and wet spots, where water tends to move to. DRONES: Drones have potential for flying low over the farm with sensors whenever needed. Though they are very stable, the helicopter-type drones don't oper- ate well in wind because they don't have enough boost, Brown said. But the major obstacle to their commercial use is uncertainty about how they will be licensed. He expects that the Federal Aviation Authority will issue rules this winter to address safety concerns, such as the risks of interfering with aircraft or crashing to the ground and hitting someone. "People are chomping at the bit to use these tools," he said. "It's just hard to figure out how to get them licensed." SPACIAL INTERPOLATION: Spacial interpolation software is used to process data collected by the various sensors in order to generate continuous maps from a limited number of data points. It assumes a greater like- lihood that locations close to a data point are similar in value than locations further away. • Matteo Poggio, a PhD student at WSU, works on a near-infrared probe, which shines a light into the soil and can indicate the soil mineralogy and organic matter content.