{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,17]],"date-time":"2026-06-17T11:12:01Z","timestamp":1781694721264,"version":"3.54.5"},"reference-count":37,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2019,10,14]],"date-time":"2019-10-14T00:00:00Z","timestamp":1571011200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100005825","name":"National Institute of Food and Agriculture","doi-asserted-by":"publisher","award":["2015-68007-23133"],"award-info":[{"award-number":["2015-68007-23133"]}],"id":[{"id":"10.13039\/100005825","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100005825","name":"National Institute of Food and Agriculture","doi-asserted-by":"publisher","award":["2018-67003-27406,"],"award-info":[{"award-number":["2018-67003-27406,"]}],"id":[{"id":"10.13039\/100005825","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000015","name":"U.S. Department of Energy","doi-asserted-by":"publisher","award":["DESC0018409 and DE-FC02-07ER64494"],"award-info":[{"award-number":["DESC0018409 and DE-FC02-07ER64494"]}],"id":[{"id":"10.13039\/100000015","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Despite the new equipment capabilities, uneven crop stands are still common occurrences in crop fields, mainly due to spatial heterogeneity in soil conditions, seedling mortality due to herbivore predation and disease, or human error. Non-uniform plant stands may reduce grain yield in crops like maize. Thus, detecting signs of variability in crop stand density early in the season provides critical information for management decisions and crop yield forecasts. Processing techniques applied on images captured by unmanned aerial vehicles (UAVs) has been used successfully to identify crop rows and estimate stand density and, most recently, to estimate plant-to-plant interval distance. Here, we further test and apply an image processing algorithm on UAV images collected from yield-stability zones in a commercial crop field. Our objective was to implement the algorithm to compare variation of plant-spacing intervals to test whether yield differences within these zones are related to differences in crop stand characteristics. Our analysis indicates that the algorithm can be reliably used to estimate plant counts (precision &gt;95% and recall &gt;97%) and plant distance interval (R2 ~0.9 and relative error &lt;10%). Analysis of the collected data indicated that plant spacing variability differences were small among plots with large yield differences, suggesting that it was not a major cause of yield variability across zones with distinct yield history. This analysis provides an example of how plant-detection algorithms can be applied to improve the understanding of patterns of spatial and temporal yield variability.<\/jats:p>","DOI":"10.3390\/s19204446","type":"journal-article","created":{"date-parts":[[2019,10,14]],"date-time":"2019-10-14T12:14:05Z","timestamp":1571055245000},"page":"4446","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":21,"title":["Capturing Maize Stand Heterogeneity Across Yield-Stability Zones Using Unmanned Aerial Vehicles (UAV)"],"prefix":"10.3390","volume":"19","author":[{"given":"Guanyuan","family":"Shuai","sequence":"first","affiliation":[{"name":"Department of Earth and Environmental Sciences, Michigan State University, East Lansing, MI 48823, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4230-5684","authenticated-orcid":false,"given":"Rafael A.","family":"Martinez-Feria","sequence":"additional","affiliation":[{"name":"Department of Earth and Environmental Sciences, Michigan State University, East Lansing, MI 48823, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jinshui","family":"Zhang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing 100875, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shiming","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Earth and Environmental Sciences, Michigan State University, East Lansing, MI 48823, USA"},{"name":"Institute of Forest Resource Information Techniques, Chinese Academy of Forestry, Beijing 100091, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Richard","family":"Price","sequence":"additional","affiliation":[{"name":"Department of Earth and Environmental Sciences, Michigan State University, East Lansing, MI 48823, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2090-4616","authenticated-orcid":false,"given":"Bruno","family":"Basso","sequence":"additional","affiliation":[{"name":"Department of Earth and Environmental Sciences, Michigan State University, East Lansing, MI 48823, USA"},{"name":"W.K. Kellogg Biological Station, Michigan State University, Hickory Corners, MI 49060, USA"},{"name":"Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI 48824, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,10,14]]},"reference":[{"key":"ref_1","unstructured":"Schimmelpfennig, D. (2016). Farm Profits and Adoption of Precision Agriculture."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1464","DOI":"10.2134\/agronj2004.1464","article-title":"Corn Response to Within Row Plant Spacing Variation","volume":"96","author":"Lauer","year":"2004","journal-title":"Agron. J."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"577","DOI":"10.2134\/agronj2010.0405","article-title":"Agronomic Responses of Corn to Stand Reduction at Vegetative Growth Stages","volume":"103","author":"Coulter","year":"2011","journal-title":"Agron. 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