Citation: Akumu, C.E.; Oppong, J.N.; Dennis, S. Examining the Percent Canopy Cover and Health of Winter Wheat in No-Till and Conventional Tillage Plots Using a Drone. Agriculture 2024, 14, 760. https:// doi.org/10.3390/agriculture14050760 Academic Editor: Jianli Song Received: 28 February 2024 Revised: 1 May 2024 Accepted: 9 May 2024 Published: 14 May 2024 Copyright: © 2024 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). agriculture Article Examining the Percent Canopy Cover and Health of Winter Wheat in No-Till and Conventional Tillage Plots Using a Drone Clement E. Akumu *, Judith N. Oppong and Sam Dennis Department of Agricultural Science and Engineering, College of Agriculture, Tennessee State University, Nashville, TN 37209, USA; joppong@tnstate.edu (J.N.O.); sdennis@tnstate.edu (S.D.) * Correspondence: aclemen1@tnstate.edu; Tel.: +1-615-963-5616; Fax: +1-615-963-7798 Abstract: The percent canopy cover and health of winter wheat are important crop performance indicators. Thus, understanding how tillage management practices affect these indicators is beneficial for improving crop performance and consequently yield. The availability of high-resolution drone data with spectral characteristics provides an opportunity to examine the percent canopy cover and health of winter wheat in different tillage systems. This is because the use of drones provides real-time high spatial resolution and temporal images to effectively monitor winter wheat conditions throughout the growing season. Nonetheless, very limited studies have utilized drone data for assessing the percent canopy cover and health conditions of winter wheat for different tillage practices. This study aimed to examine the percent canopy cover and health of winter wheat in no-till and conventional tillage plots using a drone. We used the mean Normalized Difference Vegetation Index (NDVI) ± Standard Deviation (SD) (0.89 ± 0.04) of winter wheat for the growth stages of tillering, jointing, and boot/heading to generate the percent wheat canopy cover. The Normalized Difference Red-Edge (NDRE) produced for winter wheat at the middle and late growth stages was used as a proxy for wheat health condition. We found that the mean percentage canopy cover of winter wheat was about 4% higher in no-till compared to conventional tillage plots in most of the growing season. The mean NDRE ± standard error (SE) of winter wheat was about 0.44 ± 0.01 and 0.43 ± 0.01 for no-till and conventional tillage plots, respectively, during the mid- and late growth stages. There was no significant difference in either the percent canopy cover or health of winter wheat between no-till and conventional tillage plots. The results generated in this study could be used to support farmers’ decision-making process regarding tillage practices and wheat crop performance. Keywords: percent canopy cover; health; wheat; no-till; conventional tillage; drone 1. Introduction Winter wheat is an important small grain crop that is generally used worldwide to enhance food security [1,2]. For example, in the United States (US), wheat is ranked third among field crops in production, planted acreage, and gross farm receipts after corn and soybeans. Farmers supplied about 1.8 billion bushels of wheat from 37.3 million acres of harvested area in the year 2023/2024 [3]. The percent canopy cover and health of winter wheat are essential performance charac- teristics for understanding crop physiological condition, biomass, and yield potential [4–6]. Drone multispectral images could be easily used to infer the percent canopy cover and health of winter wheat. This is because wheat responds differently to spectral reflectance information from drones [7]. Based on wheat reflectance data, the percent canopy cover and health could be easily determined and monitored in agricultural fields. Vegetation indices derived from spectral bands such as the Normalized Difference Vegetation Index (NDVI) and Normalized Difference Red-Edge (NDRE) are generally used as proxies for crop condition and structure that include but are not limited to canopy cover and crop health [8–10]. The NDVI is a ratio of red (640–670 nm) and near-infrared (850–880 nm) Agriculture 2024, 14, 760. https://doi.org/10.3390/agriculture14050760 https://www.mdpi.com/journal/agriculture