Dead Concord Grapes
We have enjoyed our grapes for 30+ years (and they were planted probably in the 1970's by previous homeowner). We have seedless green and red,as well as seeded red and purple, including what looks like concord grapes (though not having planted them, we don't know for sure the varieties). Anyway, this past summer, our "concord" grapes were growing so well, had formed purple grapes, and were looking good. Out of the blue, the leaves started turning yellow and dying. We tried watering them (though they have NEVER been watered in the past). All of the other grapes were, and remained, healthy and strong and produced abundantly. For unknown reasons (which is why we are writing), our Concord grapes eventually dried up and died. Our neighbors also have concord grapes growing, but theirs are healthy and strong. I just can't figure it out. Thanks for any help!
Douglas County Oregon
This sounds unusual enough that you should probably come in to the Master Gardener clinic and discuss this. When a vine stops growing in mid to late season it is usually not a biotic disease, they normally take a few seasons to kill a vine. Something like Armillaria root rot could do it but over a couple seasons. The vine looks like the leaves just wilted from a lack of moisture and nutrients. That would mean that something either killed the roots or girdled the vine near the ground. Only options I can think of are voles or field mice eating around the trunk near the ground level, or gophers eating the roots. Most diseases cause gradual decline.
Thanks for taking the time to answer our query. We do have Thompson's mole/gopher in the fields around our home, but have actively been killing them, and there are no mounds anywhere near the grapes. I guess it is a mystery. Perhaps if we saw open the base stump and roots, we will find some kind of insect damage there. Thanks again!