Issue link: http://read.dmtmag.com/i/333548
4 0 V I N E YA R D & W I N E RY M A N A G E M E N T | J u l y - A u g 2 014 w w w. v w m m e d i a . c o m because they directly tell you how the plant "feels." Measuring vine water use will help determine the level of water deficit a vine is experiencing. As soil moisture declines, transpiration and photosynthesis are reduced. Regulated water deficits are a tool for viticulturists to limit vine vigor, create vine balance and achieve the phenological maturity and quality desired. Moderate or extreme defi- cits during a heat event, however, can cause vines to stop transpir- ing and exacerbate the negative impacts of heat stress and damage. When the vine's transpiration rate is at its maximum relative to evaporative demand, the vines are not experiencing a water deficit. They will reduce their transpira- tion rate relative to the maximum rate due to a soil moisture deficit. Irrigating prior to a forecasted heat event can help the vines protect themselves by setting up a condi- tion for maximum transpiration. Fruition Sciences has developed sap flow sensors that continually measure vine water use via transpi- ration and compare it to evapora- tive demand. The information from the sensors is relayed wirelessly and can be viewed on the website or app. The sensors can also help viticulturists see how long an irri- gation will impact the transpiration rate and fine-tune the frequency and quantity of irrigation. This can help save water and improve vine health and grape quality. MADE IN THE SHADE Vine transpiration alone is not always enough to protect grape clusters from heat damage. The intensity of incoming radiation on bunches can be reduced by natural shading provided by the canopy. A good canopy should be established early in the season through careful management of pruning and timely suckering. It is important that vines have adequate, but not excessive, soil moisture following bud break to thrive in the period of grand growth. Vine water flow is key to ensure proper leaf area growth and nutri- ent distribution. Therefore, moni- toring vine transpiration is not only useful to assess water deficit but also to diagnose overall vine leaf area development and health. It is also important that vines have adequate nutrition so that nutrients are not limiting factors to canopy development. Yet too much shade and con- gestion of leaves and lateral shoot growth around the clusters can be problematic. Clusters need expo- sure to dappled sunlight to ripen evenly, and air flow around the clusters is critical to avoid fungal diseases. It is sometimes neces- sary to remove leaves or lateral shoot growth, focusing on remov- One BirdGard Super PRO Wireless can control birds in up to 48 acres The Bird Gard SuperPRO Controller/transmitter can broadcast distress calls to receivers up to 1000 ft in all directions. One Controller/transmitter can control up to eight 4-Speaker Wireless Receivers. No need to buy 8 complete Bird Gard Super PROs. Each 4-Speaker Wireless Receiver protects up to 6 acres. Buy 2, 3, 4, up to eight 4-Speaker Wireless Receivers to protect up to 48 acres. You not only get wireless speakers, but also the distress calls randomly jump from speaker to speaker keeping the birds from getting used to the sounds. A limited special price for one BirdGard SuperPRO Controller/transmitter & one 4-Speaker Wireless Receiver is $799 (List $1050). Each additional 4-Speaker Wireless Receiver which covers up to 6 acres is $399 (list:$520). More and more vineyard managers are replacing netting with the Bird Gard PRO series. "Last year we got the SuperPRO Wireless. Had the starling flocks been there, we would have lost $20,000-$30,000 worth of grapes," Manager, Hazlitt 1852 Vineyards BirdGard Wireless JWB Marketing LLC 800.555.9634 For more discounts on the Bird Gard go to : birddamage.com SOIL & CELLAR REMI COHEN