{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,1]],"date-time":"2026-04-01T06:21:02Z","timestamp":1775024462484,"version":"3.50.1"},"reference-count":25,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2012,1,16]],"date-time":"2012-01-16T00:00:00Z","timestamp":1326672000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This work provides a design for two types of sensors, based on the thermal dissipation and heat ratio methods of sap flow calculation, for moderate to large scale deployments for the purpose of monitoring tree transpiration. These designs include a procedure for making these sensors, a quality control method for the final products, and a complete list of components with vendors and pricing information. Both sensor designs were field tested alongside a commercial sap flow sensor to assess their performance and show the importance for quality controlling the sensor outputs. Results show that for roughly 2% of the cost of commercial sensors, self-made sap flow sensors can provide acceptable estimates of the sap flow measurements compared to the commercial sensors.<\/jats:p>","DOI":"10.3390\/s120100954","type":"journal-article","created":{"date-parts":[[2012,1,16]],"date-time":"2012-01-16T11:14:14Z","timestamp":1326712454000},"page":"954-971","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":47,"title":["Sap Flow Sensors: Construction, Quality Control and Comparison"],"prefix":"10.3390","volume":"12","author":[{"given":"Tyler W.","family":"Davis","sequence":"first","affiliation":[{"name":"Department of Civil and Environmental Engineering, University of Pittsburgh, 3700 O\u2019Hara Street 941 Benedum Engineering Hall, Pittsburgh, PA 15261, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chen-Min","family":"Kuo","sequence":"additional","affiliation":[{"name":"Department of Civil and Environmental Engineering, University of Pittsburgh, 3700 O\u2019Hara Street 941 Benedum Engineering Hall, Pittsburgh, PA 15261, USA"},{"name":"Department of Hydraulic and Ocean Engineering, National Cheng Kung University, Tainan City, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xu","family":"Liang","sequence":"additional","affiliation":[{"name":"Department of Civil and Environmental Engineering, University of Pittsburgh, 3700 O\u2019Hara Street 941 Benedum Engineering Hall, Pittsburgh, PA 15261, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pao-Shan","family":"Yu","sequence":"additional","affiliation":[{"name":"Department of Hydraulic and Ocean Engineering, National Cheng Kung University, Tainan City, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2012,1,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"589","DOI":"10.1093\/treephys\/21.9.589","article-title":"An improved heat pulse method to measure low and reverse rates of sap flow in woody plants","volume":"21","author":"Burgess","year":"2001","journal-title":"Tree Physiol"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"9","DOI":"10.2480\/agrmet.37.9","article-title":"A heat balance method for measuring water flux in the stem of intact plants","volume":"37","author":"Sakurtani","year":"1981","journal-title":"J. Agric. Meteorol"},{"key":"ref_3","first-page":"81","article-title":"Une nouvelle method pour la mesure du flux de s\u00e8ve brute dans le tronc des arbres","volume":"42","author":"Granier","year":"1985","journal-title":"Ann. Sci. For. Res"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"113","DOI":"10.1016\/0168-1923(94)90094-9","article-title":"Significant historical developments in thermal methods for measuring sap flow in trees","volume":"72","author":"Swanson","year":"1994","journal-title":"Agric. For. 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