New inexpensive dendrometers for monitoring crop tree growth Presented at the 2008 Irrigation Show, Innovations in Irrigation Conference, November 2-4 in Anaheim, CA

摘要

A fast-responding dendrometer is needed for measuring tree growth responses (daily or hourly) to drought, fertilization stress and other stresses. This study reports on operational comparisons between new, inexpensive automatic point and band contactdendrometers. Eighteen point and five band dendrometers were installed on pecan tree trunks and branches during the 2005 growing season, and their performance and measurements were compared by analyzing data downloaded weekly. Data indicated that the point dendrometer was accurate. However, band dendrometers may underestimate tree growth (average measured value by a band dendrometer was half that measured by the point dendrometers), and they may not be able to measure the hourly diameter change of small-diameter branches over several days. Point dendrometers were found to be suitable for large-scale tree growth measurements and water and fertilizer stress monitoring due to their fast response (hourly or faster), ease of construction and installation, and low expense (<40 dollar each).