Measurement of turf height and growth using a laser distance device

Abstract

Growth or yield is an important characteristic to measure in crop science experiments. Turf researchers often use rulers or harvest grass clippings to measure growth and yield, respectively. Rising plate meters or floating disk meters are used for nondestructive measurements of forage canopy height to estimate herbage biomass, but this technique is not commonly used by turf scientists. Using the rising plate concept and integrating new technology, our objective was to develop an easy‐to‐construct, low‐cost device that could rapidly and accurately measure canopy height, growth, and estimate yield in turf research. A device called the “Turf Height Tester” with a floating platform and a laser distance measurement tool was constructed within a US$167 budget. The tester was able to precisely measure recently mown turf canopy height at the tested bench heights of 4.9–10.2 cm. The Turf Height Tester was advantageous for comparing the growth of turfgrasses with contrasting growth rates, and turf response from N fertilizer applications in a nondestructive manner. The tester, which outputs data via Bluetooth to the nearest 0.1 mm, correlated well with other turf canopy height measuring tools but had a lower CV. Collecting ∼18 measurements per minute, the tester allows for data collection from 1.8 plots per minute (includes 5 pre‐ and 5 post‐mowing measurements) compared with the more labor‐intensive practice of harvesting and weighing grass clippings from a rotary mower with a bagging attachment at 0.2 plots per minute. Further, there was a strong relationship across experiments (R2 = .62–.94) between growth measurements using the tester and dry matter clipping yield.

Investigation of cool‐season species, seeding rate, and nitrogen fertilization in sod production: II. Management and shelf‐life

“…The mean hourly outside air temperature and internal temperature within the center of twenty four sod rolls during 72-h storage after harvest in the spring at 20 months after planting (MAP) in Indiana and Minnesota, and after harvest in the autumn at 24 MAP in Indiana and Minnesota dry matter clipping yield and with a turf height tester during the 2019 growing season in Indiana, which is in agreement with Patton and Braun (2020). Therefore, growth rates calculated by the turf height tester at both sites is further discussed herein.…”

“…Similarly, two to five more required mowing events per year in tall fescue compared to Kentucky bluegrass has also been observed in a current multiple year experiment (R. Braun & A. Patton, unpublished data, 2020). However, growth rate can vary among cultivars within a species, especially Kentucky bluegrass (Bonos et al., 2000; Patton & Braun, 2020).…”

“…where is the turf height (cm) determined at time 1 ( t 1 ), is the turf height determined at time 2 ( t 2 ), time interval (days) is t 2 – t 1 (Patton & Braun, 2020). The combined average growth rate (cm d −1 ) was calculated from the multiple collection timings for each site prior to analysis.…”

“…To help differentiate growth rate (i.e., the change in height or the growth of the turf) differences, turf height was measured with a turf height tester and used to calculate the growth rate as in Patton and Braun (2020) at eight different timings in 2019 and 2020 in Indiana and two different timings in 2020 in Minnesota. More specifically, five measurements were collected per plot immediately after mowing and then again 7 to 10 d later before mowing to assess the amount of growth from the previous mowing as influenced by treatments.…”

Management, harvest, and storage characteristics of low‐input cool‐season turfgrass sod mixtures

“…Turf height was measured with a turf height tester and used to calculate the growth rate of the turf as in Patton and Braun (2021) at eight timings in 2019 and 2020 in Indiana and seven timings in 2020 and 2021 in Minnesota. More specifically, five measurements were collected in each plot with the turf height tester immediately after mowing and then again 7–10 d later before mowing to assess the amount of growth from the previous mowing as influenced by treatments.…”