Issue link: http://winesandvines.uberflip.com/i/137110
JULY NEWS Vine Water Use From a Distance Technology to remotely measure thermal energy may help with irrigation N MARTIN MENDEZ apa, Calif.—At a recent meeting of the Napa Valley Vineyard Technical Group devoted to irrigation, Martin Mendez, a senior research scientist at E. & J. Gallo Winery, discussed new technology to help growers know when to apply irrigation water. Remote sensing using thermography and energy balances have become practical for assessing large areas instead of This thermal image of vines shows a wide individual leaves or vines. They operate temperature difference among leaves. on a simple principle: Transpiring plants have lower leaf temperature than those An expensive thermographic camera that aren't giving off water. flown over the vineyard, or winesandvines.com In fact, Mendez said there is a even tied to a balloon or inLearn more: Search keywords linear correlation between stostalled in a satellite, can mea"Remote thermography." matal conductance and temsure temperature and locate perature; you can calibrate measurements warm and cool areas (i.e, those with less with a leaf covered with water versus or more water being transpired). one covered with Vaseline, which inhibits Vegetation indexes are other approaches transpiration, although a more practical to remote sensing; perhaps the most comapproach is to look at the difference bemonly used is NDVI (Normalized Differtween air and leaf temperature. ence Vegetation Index), which can be used to estimate plant leaf area based on the different reflectance of light from plants at various wavelengths. It's also important to differentiate between actual vine evapotranspiration (ETa) and potential (ETp), which is more commonly referenced. One approach is SEBAL (Surface Energy Balance Algorithm for Land), which combines spectral radiance readings from satellite-based sensors with actual meteorological data to calculate the energy balance at the earth's surface. It produces water consumption, or actual evapotranspiration, and biomass production of agricultural crops and native vegetation. Mendez noted that methods of evaluating proper irrigation levels are evolving to give a better indication of vineyard health and account for differences between and within vineyards. —Paul Franson The original, BOTTLE-MATIC-II 3 YEAR WARRANTY INCLUDED Front and Back! MADE IN USA! 21 day trial $1800 for Wines & Vines Readers! Front & Back! Label any cylindrical container fast and accurately from ½" to 8" diameter, @ Speeds of 1200 Pcs. per hour. NOT A CHEAP, IMPORTED KNOCK-OFF! ISPENSA-MATIC DLabel Dispensers STOP Wasting Time Labeling by Hand! Price subject to change without notice. 28220 Playmor Beach Rd, Rocky Mount, MO 65072 Call Toll Free: 1 (800) 325-7303 or (573) 392-7684 FAX:(573) 392-1757; E-mail: info@dispensamatic.com Web: http://www.bottle-labeler.com 2/01/10 Win es & V i n es JU LY 20 13 15