Marquette problem

[WineYooper]

I need help with this, please. Started to notice this on one vine and now am seeing on multiple Marquettes. Does not seem to be affecting the Frontenacs yet but would like to address before catastrophe. New 36 vine planting over the past two years in the U.P of Michigan. The problem is it's 200 miles from home at my future home site, vines before house sounds right, yes. New at this and have been reading the previous posts and suspect the same as others have posted but want to be sure and address this correctly. Of course I have done everything wrong to this point, no soil test or ph check. I'm catching up but behind yet. It's going to be a tough haul. The bug/fly is the only critter that I have seen on any of them, may not even be the culprit.

 

[WineYooper]

Searching on line I think it may be Anthracnose but not sure. I know it's late but having my soil tested as well. I have a small amount of topsoil in the area with clay down deeper. The topsoil varies from about 6 inches to 18 deep. Have been hand digging posts and observed this. Takes me about 1.5 hours to dig one hole 4' deep. Looking to the future harvest that gives me the energy. Observing over 4 days I saw about 6" of new growth.

 

[grapeman]

The spots are more likely balck rot. Marquette is very susceptible to it and you need to brin it under control before you try to get a crop. Read up here on what to use and when and if you need guidance later ask for it. The shoots show either phomopsis or anthracnose also and needs control. You have a mixture of diseases. Luckily both are controlled by mancozeb products.

 

[WineYooper]

Thanks Grapeman now I can get busy. This has been brought up many times I see now that I have a name to search with. I need to use the search better before posting or reading back multiple pages for similar. Did not plan on grapes this year so not a huge disaster but with more work I may be able to help next year to get a taste. It's been extremely wet this year compared to past years so even spraying might have been tough. Next task is to find a dealer for this, are they readily available at a local greenhouse supply place?

 

[grapeman]

Mancozeb and Pencozeb are fairly common. If you can't find them ask at a local shop what is equivalent and is label approved for your pests and they should help.

 

[Chuck-crisler]

The problem with manganese based fungicide is the 67 day before harvest exclusion. He isn't harvesting this year so it isn't an issue but is something to remember for next year. Many people try to grow a 'natural' vineyard (or garden). The trouble is that nature doesn't grow that way. All you do is to provide pests (insects, mites, fungi) with a very convenient food source. If you really want to grow a good crop of anything, you need a good, diversified spray program. Here are some of my sources:

http://nysipm.cornell.edu/factsheets/grapes/default.asp
http://grapesandwine.cals.cornell.edu/extension/grape-and-wine-resources

They have pictures of problems, explanations of life cycles, spray schedules, evaluations of effectiveness of different chemicals vs. pests, susceptibility of different varieties to pests and chemical treatments and more.

 

[grapeman]

Good point about the pre-harvest interval (PHI) and resources Chuck. We aren't an all inclusive resource here for spray recommendations and knowledgebase. We try to speak of generalizations and point members in the right direction for additional information because every state has a different set of rules.

 

[WineYooper]

Could not find Mancozeb products but was able to pick up fruit tree spray by Bonide here that was suggested at two places. Sprayed last weekend and will do it again this next weekend. Strung some more cable and three more posts in. Only twelve more to go. Lots of rocks so no augering, hand dug around 1 1/2 hours a hole. Three nice clusters of grapes on the 2 year old Marquette, I will probably let go to get a small taste, maybe pull one off. Signs of maybe what's to come!

 

[grapeman]

The generic Bonide Tree Fruit spray is probably the least effective product available for what you have. It is intended to be a spray for everything product and does a fair to poor job at all of them. It may take more looking for the proper sprays, but you will use less in the end and do a lot better job.

Look on Ebay or elsewhare for products. It is easy to search for products. Check out Mancozeb. Here is a link to a pint of it for less than $15
http://www.ebay.com/itm/NEW-BONIDE-...011?pt=LH_DefaultDomain_0&hash=item5d4b637ddb

 

[Chuck-crisler]

This is what I use.

http://www.domyownpestcontrol.com/manzate-prostick-and-fungicide-p-2765.html

 

[WineYooper]

Thanks Grapeman, I did see some on line before I picked up the fruit tree spray and was concerned about the effectiveness but did not have time to wait since I was leaving town the next night. I will be ordering some of this and like that it is small amount since I don't have a large planting. If there is a life to this stuff that would insure I am using good product.

 

[grapeman]

Only make up what you need at a time and the rest will last quite some time as long as it is dry (powder) or not frozen (liquid).