Thursday, November 7, 2019

Grapevine water use in Central New Mexico.


NMSU viticulture has initiated a study to determine how much water grapevines growing in central New Mexico require to produce a 3-6 ton/acre crop of wine grapes destined for sparkling wine production. 


                An exploratory, observational study was initiated in 2018 at a  ~30 acre commercial vineyard at the Pueblo of Santa Ana, Sandoval County, NM (just north of Bernalillo, NM, east of I-25), to measure and calculate the seasonal water requirement of three Vitis vinifera winegrape varieties: Chardonnay, Pinot Meunier and Pinot Noir, grown for sparkling wine production. Although it is widely established that wine grape growers can more efficiently manage their irrigation systems and the amount of water applied to grapes once the grapevine’s water requirement for a desired fruit composition and yield level is known (Williams 2001), this has not been accomplished within New Mexico.


Figure 1. Average soil moisture (%) at 6 depths in three blocks at Santa Ana Vineyard , NM, from October 31, 2018 to October 26 , 2019.
In figure 1 above, notice that the soil moisture (%) in the Pinot Meunier block was substantially greater across all depths except 1000 mm. This block is located at the lowest elevation compared to the other two and the alluvial soil, with an associated greater water holding capacity may have played a role in this trend. We will repeat the study next year with more replications to determine if this is the case. 

Close up of HH2 unit being used to capture soil moisture readings at 100, 200, 300, 400, 600, and 1000 mm  under the trellis in the vine row at Santa Ana Pueblo Vineyard, Sandoval County, NM.


Figure 2. Stem water potential of three varieties during the growing season 2019. The dotted line indicates level of stem water potential (-1.0 MPa) that water stress is likely to occur




Scholander pressure chamber used to determine level of water status of grapevines during the growing season. 



Wikepedia: pressure bomb_Check out the explanation of a pressure chamber and how it is used to determine water potential ( or how water stessed ) a plant maybe at any given time. 





































































Monday, November 4, 2019

Mr.George Zhuang, Viticulture Farm Advisor, University of California, Fresno County Visits the Mesilla Valley

Looking east over Stahmanns Pecan Groves from mesa on the Stahman Ranch southwest of Las Cruces, NM. The Organ Mountains are in the background. From left: George Zhuang (Farm Advisor, UC in Fresno Co., CA), Daniel Goodrich (Program Coordinator, NMSU Viticulture), Gill Giese (Extension Viticulture Specialist, NMSU) and Mr. Rafael Rovirosa (Director of Operations, Stahmanns Pecans)

We were treated to a tour of Stahmann's Pecans and processing plant near Las Cruces NM on Friday November 1. Mr. Rafael Rovirosa served as our knowledgeable and gracious host throughout. We were introduced to traditional practices and cutting edge technology as pecans remain a vibrant, sustainable industry in New Mexico's  economy due to pioneers and innovators like Rafael and his family. After the tour of Stahmanns we headed west to Deming and Luna Rossa vineyard and winery owned and operated by the D'Andrea family. Mr. Paolo D'Andrea was our generous and open host, explaining both his wine-growing philosophy and techniques. Paolo grew up in a winegrowing family in Italy and after moving to the US started his own business on the edge of where a vinifera grape can grow...arid lands of southern western New Mexico.  

Mr. George Zhaung (left) and Mr. Paoloo D'Andrea of Luna Rossa Vineyard and Winery, Deming, NM share some grape growing information and camaraderie in Paolo's vineyard. 
Mr. George Zhaung (left) and Mr. Gordon Steel of Rio Grande Vineyard and Winery near Las Cruces, NM, discuss some of Gordon's wines, with special reference to his Quene Tendre or French Colombard wine that Gordon makes as an "orange" wine.

Gordon Steel's family has been in New Mexico since the 1800's. After a military career, Gordon literally and figuratively returned to his roots, establishing his vineyard and winery in the Mesilla Valley just outside Las Cruces. He has grown grapes and made wine commercially for over 15 years. Gordon has studied and traveled thorough out the wine world to bring knowledge and 'know how'  to bear on his line up of high quality wines.












































Mr.George Zhuang, University of California Farm Advisor for Fresno County, presented a talk on: