A cabbie in Eastern Europe once told me: “Never trust lawyers, priests and weathermen” (not necessarily in that order).
So, last Saturday I pruned the Montepulciano block since the forecast was for drizzle in the foothills. The vineyard is NOT in the foothills.
Then, at 4 am on Monday morning…. I woke up to the sound of pouring rain.
Even thought I live about four and a half miles to the east of the vineyard (and much closer to the foothills of the San Gabriel Mountains) I spent that day watching, with some anxiety, the weather radar for the area of the vineyard.
I had to start pruning. The lignified canes were starting to bud out, especially the Montepulciano. As I was tired from mowing the (relatively modest) cover crop, and removing the bird nets took longer than expected, AND I wanted to minimize down time for James (who had come by to see the process), AND since the canes were weeping after being cut, I opted to forgo the pruning compound (which I’d left downhill, anyway).
So, between diaper changes, feedings, calls from work and checking wunderground.com, I scoured the web for information about Euptypa, hoping to find something that would reassure me that my vines won’t get infected.
Eutypa is type of mold which infects fresh (or relatively fresh) pruning wounds. Once it sets up shop, it causes woodrot and eventual dieback of the vine.
The way it propagates itself is by releasing spores which were dormant during the winter. It does this with the first spring rains. The spores become airborne and make their way into pruning wounds.
Given that this has been a dry winter and these rains were essentially the first of the season, my concern was high.
However, from the resources below, it seems that Eutypa is more prevalent in areas with over 16 inches of annual rainfall. Hopefully, the “chance of rainfall” projected for tonight will not contribute to that total.
The following is a short list of resources about Eutypa:
- Grapevine Canker Disease: Our Leading Vineyard Pest Problem (PDF download)
- UC Pest Management Guidelines
- Eutypa Dieback
- Winegrapes: Eutypa
- Canker Diseases