Saturday, June 30, 2018

How green is my valley.

I don't know if it's me, the light quality today, or the fact that Vinoland's grapevines got a little extra TLC last night, but everything in Vinoland just looks wonderfully verdant today.  The Pinot grigio grapes are definitely a little shinier: I'll explain.
In the never ending quest to produce good quality grapes from disease free vines, preventing pests from damaging the grape crop calls for a combination of techniques, or integrated pest management (IPM).  Along with cultural practices, sometimes chemical control, the use of pesticides, can be more effective in controlling pests (in the greater context of a broad IPM strategy).  Yesterday evening was the first time Stylet-Oil (SO) was used on the grapevines (with a little Mettle® fungicide thrown in for good effect).  SO is a little more effective against powdery mildew (Uncinula necator) (PM) in cooler growing seasons (like the one the Napa Valley is experiencing this year) versus the more conventional use of sulphur.  Sulphur needs warmer temperatures to volatize (65°F is the recognised minimum temperature required for sulphur activity against PM), whereas SO is not temperature dependent and so it acts as an eradicant, protectant and, most importantly, an antisporulant 24 hours a day.  In layman's terms, SO stops spores from growing, and insects from breathing.  And it makes baby-grapes shinier.

2 comments:

Dennis Tsiorbas said...

Makes for a neat photo too.
You two have an amazing amount of knowledge.

Vinogirl said...

NHW: Got it all out of a book/s. Oh, and hands on.