Comparison of Three Leaf Area Index Meters in a Corn Canopy

Abstract

NOTES1179 that were 1.1 to 1.8 m wide, every position on the bench hand-spraying. The realized effects have been several: reductions in costs for disposal of excess spray as hazardwas sprayed by more than one nozzle, an important consideration because the nozzles can be plugged. The ous waste and disposal of protective suits, less disruption to other greenhouse labor operations, more flexibility quantity of pesticide, which was suspended in the air as a fog, settled on all surfaces if vents were kept closed in choice of spraying times, elimination of hazard to others in greenhouses near the sprayed bay, more preand the air was not circulated.Unlike the Dramm Autofog, the automated spray sysdictable spray applications, reduced exposure and handling of spray material by employees with concurrent tem is not portable. Major costs were the air pressure system, the mixing tank, and the wiring for the reduction in employer's liability, reduced reluctance to spray and better control of pests, and elimination of controls, but the Flora-mist nozzle was very inexpensive at Ͻ$2.00. One cost-cutting option is to use manual some of the variability found with hand-spraying. switches outside the spray area for turning off the air Acknowledgments

Determining the protective effect of agricultural crops on the soil erosion process using a field rainfall simulator

“…In addition, the values of LAI measured optically decrease with the loss of chlorophyll and with changing color, though the leaf area generally remains the same and so the interception characteristics are also almost constant. According to Wilhelm et al (2000), optical methods for determining LAI are unreliable at higher values and the results that they produce are undervalued, as was confirmed by our measurements. Due to the unreliability of determining LAI using optical measurements in summer periods, LAI was also measured three times by a destructive method.…”

A visible band index for remote sensing leaf chlorophyll content at the canopy scale

“…LAI was measured at five locations per plot with an AccuPAR Ceptometer (Decagon Devices, Pullman, Washington, USA) using the procedure described by Wilhelm et al (2000). The five locations were at the plot center, and at the center point of the north-east, north-west, south-west, and south-east plot quadrants around the plot center.…”

Developing in situ Non-Destructive Estimates of Crop Biomass to Address Issues of Scale in Remote Sensing

“…The LP-80 is comparable to other commonly used ceptometers, such as LAI-2000 ® and SunScan ® , when evaluated against destructive measurements of LAI in maize fields under a wide array of sky conditions [50]. The LP-80 is connected to a datalogger and consists of a probe containing 80 independent photosensors, 1 cm apart ( Figure 2C).…”