An Improved Bead Thermistor Anemometer for Use in Plant Canopies. J. W. Oldman, Ruakura Soil and Plant Research Station, Private Bag, Hamilton, New Zealand. M. J. Judd and K. J. McAneney, Ruakura Soil and Plant Research Station, Private Bag, Hamilton, New Zealand. Plant Dis. 68:413-414. Accepted for publication 6 December 1983. Copyright 1984 The American Phytopathological Society. DOI: 10.1094/PD-68-413.

A small, inexpensive anemometer suitable for use in plant canopies was constructed using bead thermistors in a constant-temperature configuration. It overcomes the directional dependence associated with a single thermistor by using twin beads mounted at right angles. The anemometer was calibrated using a pendulum as a velocity standard and achieved an accuracy of ±0.03 m/sec for wind speeds in the 0–2 m/sec range. Two anemometers operated successfully within grapevine canopies for a complete season.