What can I say besides boy is it hot! After no rain in May, plenty of rain in June and now over a week in the 90's everyone is steaming in the vineyard. The plants don't mind because most vineyards have irrigation or are old vines with extensive root systems. Actually, the heat will do the vines some good after such a cool spring. It is hard to stay motivated out there. Even the cover crops are starting to take a hit. Here are a few shots of clover under the trellis down at Channing Daughters Winery. These photos were taken on July 12th just before we moved into our second week of a heat wave.

The clover seems to be holding up well. This is the second season at this site and it came back nicely this year. Weeds are not as much of a problem in this trial but there is some mugwort that may be hard to control since it isn't being mowed.

Our summer intern, Matt Gura, will be posting a series of interviews he is conducting with the growers that are participating in the under trellis cover crop study. Here is his first interview with Jim Thompson, vineyard manager at Martha Clara Vineyards.

Greetings!

I recently had the pleasure of meeting with Jim Thompson to discuss his experiences with under-vine cover crops.  Jim manages Martha Clara Vineyards, where the CCE-SC grape program has the replicated trial evaluating under trellis cover crops.

Prompted by observing practices in the western US and Europe, Jim has been interested in alley and under-vine cover crops for many years.  The exposure led him to critically reflect on the impact of conventional practices involving herbicide use: “As it became more obvious that herbicides were going to become an issue for growers, like leaching, disruption of the dynamics of the ecosystem on the vineyard floor…and it became more popular to think about these issues, I felt that [covercrops] just made sense.”

When Jim was confident that the vines where he observed various cover cropping techniques did thrive, he recognized the relevance such strategies could have in his own vineyard:  “[My] vines are crazy vigorous, and in a region where some years you can get 10 inches of rain in June, what better way to soak up some of that water than these cover crops.”

                Jim has experimented with wall to wall cover crops in years past, but he primarily maintains an herbicide strip under the vine.  As he continuously follows under-vine cover crop research, I asked him if he considered the results positive such that he may be ready to adopt the practice: “Encouraging, but not positive.  We haven’t hit it yet as far as I’m concerned.”  As to what particularly concerns him, Jim replied: “Simply the management of them.  As they get too tall and get too close to the bottom of the vines, an issue is moisture retained by those groundcovers that transpires into the canopy.  If the soil is bare, then that would never happen.  There’s more to think about.”

Interview by Matt Gura, CCE-SC intern

                                    No mow only treatment at Martha Clara on July 9th.

We spent yesterday with Cornell University Professor Justine Vanden Heuvel touring our under trellis cover projects. She has similar projects going on in the Finger Lakes but is focusing her research on annual cover crops as opposed to perennial ones like we have in our trials. She brought her two grad students that are working on these projects. Here is a photo of the whole group over at Old Field.

We also stopped at Martha Clara, Mattebella and One Woman to see how the various trials are progressing. It is always nice to get different perspectives and share ideas on topics that are new and constantly evolving. One of the things we discussed was even though they are seeing differences in nitrogen levels from petiole samples there are not significant difference in vine growth between treatments or fruit parameters at harvest. This may be because they are not using a permanent cover crop year round like we are. They need to hill up their vines to protect the graft union in the event of an extremely cold winter. They are tilling in their cover crop each fall which may be providing a boost of nitrogen. Will be interesting to see how their trials progress compared to ours. We'll keep you posted!