Description
Throughout the many decades of grassland and forage research, practitioners have used many different methods to assess botanical composition. While a few of these methods have proven to be accurate and efficient, there has been limited direct comparison between methods. The objective of this study was to determine an accurate and efficient method to determine botanical composition for researchers, practitioners, and students. Six farms with two pastures each were monitored across the state of Kentucky. Sampling started fall 2020 and continued through fall 2022 with measurements taken three times a year using the following measurement techniques: step point, visual estimation, occupancy grid, and point quadrat. The same twenty random locations were sampled with each technique with the exception of step point, where a minimum of 100 random locations were sampled. The point quadrat method was utilized as a reference method for accuracy to the other methods. The results of this research show that when directly compared to results of the reference method the occupancy grid method had the highest similarity. The occupancy grid method was also less prone to over and under-estimation and had the highest correlation coefficient using Pearson’s method of 0.87 to 0.99 across all species. Visual estimation method correlation ranged from 0.75 to 0.98 across all species. Step point was the least correlated ranging from 0.40 to 0.90 due to its high variability recording certain species (e.g. - KY bluegrass, goosegrass, bare soil). ANOVA results showed the occupancy grid method was not significantly different at recording any species in comparison to the point quadrat method. The visual estimation method was significantly different from the point quadrat method for the following species: tall fescue, orchardgrass, other forages, and broadleaf weeds. The step point method was significantly different for these species: tall fescue, Kentucky bluegrass, and broadleaf weeds. Overall, the occupancy grid method was the most similar to the reference method (point quadrat), as well as the most efficient method of botanical analysis.
Included in
Agricultural Science Commons, Agronomy and Crop Sciences Commons, Plant Biology Commons, Plant Pathology Commons, Soil Science Commons, Weed Science Commons
A Comparison of Four Methods of Botanical Analysis in Kentucky Cattle Pastures
Throughout the many decades of grassland and forage research, practitioners have used many different methods to assess botanical composition. While a few of these methods have proven to be accurate and efficient, there has been limited direct comparison between methods. The objective of this study was to determine an accurate and efficient method to determine botanical composition for researchers, practitioners, and students. Six farms with two pastures each were monitored across the state of Kentucky. Sampling started fall 2020 and continued through fall 2022 with measurements taken three times a year using the following measurement techniques: step point, visual estimation, occupancy grid, and point quadrat. The same twenty random locations were sampled with each technique with the exception of step point, where a minimum of 100 random locations were sampled. The point quadrat method was utilized as a reference method for accuracy to the other methods. The results of this research show that when directly compared to results of the reference method the occupancy grid method had the highest similarity. The occupancy grid method was also less prone to over and under-estimation and had the highest correlation coefficient using Pearson’s method of 0.87 to 0.99 across all species. Visual estimation method correlation ranged from 0.75 to 0.98 across all species. Step point was the least correlated ranging from 0.40 to 0.90 due to its high variability recording certain species (e.g. - KY bluegrass, goosegrass, bare soil). ANOVA results showed the occupancy grid method was not significantly different at recording any species in comparison to the point quadrat method. The visual estimation method was significantly different from the point quadrat method for the following species: tall fescue, orchardgrass, other forages, and broadleaf weeds. The step point method was significantly different for these species: tall fescue, Kentucky bluegrass, and broadleaf weeds. Overall, the occupancy grid method was the most similar to the reference method (point quadrat), as well as the most efficient method of botanical analysis.
