Grapes! - Ask Extension
Hi we have some grapevines in our yard(with green seeded grapes) that the lady who used to own the house planted. We are trying to figure out what the...
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Grapes! #706937
Asked July 29, 2020, 1:04 PM EDT
Hi we have some grapevines in our yard(with green seeded grapes) that the lady who used to own the house planted. We are trying to figure out what they are! Wine, jam grapes? Type? I dn't believe they are eating grapes... And we have a problem with these every year, some kind of red dots develop on the leaves and the grapes then turn all black. We cut it down to almost nothing and it grew back but appears to be doing the same thing. and it looks like it has spread to our other trees as well, particularly our apple tree. I've attached pictures of the grape vines. Tried to attach more but only allowed 3..Thank you!
Bucks County Pennsylvania
Expert Response
Hello,
Thank you for your question.
About identifying the type of grape, we'll need more information and pictures to do so.
Here is a link with information for identification:
https://extension.oregonstate.edu/crop-production/wine-grapes/grape-variety-identification
I'll suggest you take a look at it and begin with the most common grape varieties sold to homeowners. It will also give you which kind of pictures you need to send to your extension office so they could help you. (https://extension.psu.edu/bucks-county)
About the disease: I'm confused because you write that there are red spots on the leaves which make me think of black rot, but on the picture of the leaf you sent, it looks more like phomopsis. Both diseases make the grape turn black.
So here is several link with information on this 2 diseases so you could try to identify which one you have and take action. In both case you might need to treat with fungicide, so it is very important that you could identify the disease. If you have any doubt, you can send a sample to the plant disease clinic:
https://plantpath.psu.edu/facilities/plant-disease-clinic
I hope it will help you.
Black rot:
https://extension.psu.edu/black-rot-on-grapes-in-home-gardens
https://grapesandwine.cals.cornell.edu/newsletters/appellation-cornell/2014-newsletters/issue-17/managing-black-rot/
Phomopsis:
https://ohioline.osu.edu/factsheet/plpath-fru-47
http://ipm.ucanr.edu/PMG/r302100411.html
Thank you for your question.
About identifying the type of grape, we'll need more information and pictures to do so.
Here is a link with information for identification:
https://extension.oregonstate.edu/crop-production/wine-grapes/grape-variety-identification
I'll suggest you take a look at it and begin with the most common grape varieties sold to homeowners. It will also give you which kind of pictures you need to send to your extension office so they could help you. (https://extension.psu.edu/bucks-county)
About the disease: I'm confused because you write that there are red spots on the leaves which make me think of black rot, but on the picture of the leaf you sent, it looks more like phomopsis. Both diseases make the grape turn black.
So here is several link with information on this 2 diseases so you could try to identify which one you have and take action. In both case you might need to treat with fungicide, so it is very important that you could identify the disease. If you have any doubt, you can send a sample to the plant disease clinic:
https://plantpath.psu.edu/facilities/plant-disease-clinic
I hope it will help you.
Black rot:
https://extension.psu.edu/black-rot-on-grapes-in-home-gardens
https://grapesandwine.cals.cornell.edu/newsletters/appellation-cornell/2014-newsletters/issue-17/managing-black-rot/
Phomopsis:
https://ohioline.osu.edu/factsheet/plpath-fru-47
http://ipm.ucanr.edu/PMG/r302100411.html
Hi thanks for the info. The one link you gave me to add more pictures was a dead link. I can add a few more here. What other kind of pictures would you need? The ohio link did not say anything about what kind of pictures to send? From what I read in other places thoguh, you would need to see the size of the grapes, the size and shape of the grape bunch, the shapes of the leaves, the texture and such....I'll attach a few different pictures to see if maybe that will help? We are trying to determine what they are so we can see if it would hurt to harvest them now before the black rot takes over..
There are something like 10,000 varieties of grape, so it is difficult to make an identification. It will be best if you could contact your extension office in Bucks county. They might be able to help you better than us thought the ask website.
I think you can always try to eat one grain and see how it taste.
I found this information about distinguishing between table and wine grape:
I think you can always try to eat one grain and see how it taste.
I found this information about distinguishing between table and wine grape:
Table Grapes Are Fat and Sassy. Table grapes are grown in a way to make them more physically appealing. They are larger, seedless, with thicker pulp and thinner skins to give them that ideal ‘pop’ when you eat them. Table grapes have less acidity and also less sugar than a wine grape.
Wine Grapes Are Lean and Mean. Wine grapes are grown to produce the sweetest and most potent grapes. They are smaller, riddled with seeds, have thicker skins and higher juice content (vs. pulp). Wine grapes are delicate and difficult to transport. When you eat a fresh wine grape, they ooze apart, leaving you with crunchy bitter seeds and chewy grape skin.
I'm sorry we couldn't help you more.