Odd spray

[Sage]

I was driving on the interstate and just out of The Dalles, OR was a hillside vineyard. All of the plants were sprayed with something white, pretty solid coverage. Just the lower half of the vines were covered and the top half was still green

Anyone know what it was and its purpose????

 

[spaniel]

LINK

I've never heard of doing this to grape vines but this could be it.

 

[Sage]

This was not on the trunk at all, just the lower half of the folage.

A thought did occur to me. Could it cause defoliation of the lower leaf cover to allow full sun on the grapes or for harvest??

 

[oregondabbler]

Treating the soil with lime maybe?

http://www.ovs.com/video/lime_application/liquid_lime_gypsum_appl.htm

Not much to go on -- white stuff on foliage. Perhaps they were getting a head start with preparing the soil by spraying lime for next year? The link above shows something like what you describe.

 

[Sage]

http://www.ovs.com/video/lime_application/liquid_lime_gypsum_appl.htm

Not much to go on -- white stuff on foliage. Perhaps they were getting a head start with preparing the soil by spraying lime for next year? The link above shows something like what you describe.

It did look like that, only on the lower half of the foliage. Lime combats powdery mildew?? Combination mildew control and liming the ground when they fall?

I tried hard to see if there were any grapes but I did not see any. If they were still there, they would have also been sprayed.

 

[oregondabbler]

As you already guessed, if the stuff shown in the video was what you saw, it would be sprayed after harvest.

Lime is calcium carbonate and Gypsum is calcium sulfate. These compounds wouldn't be something you'd want to apply to the grapes just before harvest. That said, I'm just a dabbler. Maybe there is some science behind doing this. If so, I'd love to hear about it

Lime and gypsum are mainly used as soil conditioners with the added benefit of adding calcium to the soil. Lime helps raise pH in acid soils. Gypsum helps open up clay soils. There are other benefits to applying gypsum.