Hello Victoria,

1. How to clean away the Western Cherry Fruit Fly problem. I'm
relatively new in this farm and I was told that it came around 5 years ago. Before that there was no problem with the fruit fly. I'm hopeful to find a solution for this.

>WCFF has been a problem for a long time, but what this person may be referring to is spotted wing drosophila (SWD), which is a relative newcomer that has largely replaced WCFF as the major cherry direct pest. Most growers manage SWD, which will also take care of WCFF. WCFF is easier to deal with as it responds well to bait sprays such as GF-120.


2. Some trees have canker. I was recommended to use REX Lime Sulfur, I bought it but it says to apply it on the dormant season. Do I need to wait till then? How to know when a tree is dormant?

>Generally yes you can damage leaves with sulfur applied during the growing season. The tree is dormant when it has lost its leaves during winter. Another timing for certain sprays is delayed-dormant timing, which is the time when the buds begin to swell in early spring. Any pest/disease management guide will give you a key to the important tree stages.  For bacterial canker on cherry in the Willamette Valley you might be better off with delayed dormant application of the lime sulfur. But, this is a really tough disease to manage with sprays on cherry, see: https://pnwhandbooks.org/plantdisease/host-disease/cherry-prunus-spp-bacterial-canker

3. Some trees have a few branches that looked as if they were dead. This was visible during the summer when the leaves were green, this branches that I mention were alive but with dead like color and the leaves curly and dark.

>Prune this dead stuff out in dry weather. It is fine to do it in the growing season, in fact summer pruning can reduce transmission of bacterial canker and promote good healing response. 

4. How long does a sweet cheery tree lives for?

>Well the productive life is probably around 20 years, but they can live much longer. Over time, production declines as disease such as bacterial canker increase. So at a certain point the cost of maintaining the trees eclipses the profits made and it is best to rip out the orchard and renew it.

5. Do you have some general information about sweet cherry trees that I can resource from?

Yes here are all the cherry resources from the OSU Extension catalog. See also the PNW Insect and Disease handbooks (referenced above) that have additional resources:

https://catalog.extension.oregonstate.edu/search/content/cherry

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Hello,

I have a few more questions regarding cherry trees... 

You recommended to use GF-120 for SWD, would this also works for controlling WCFF? Regardless of this, can you tell me when and how to apply this product please. If this doesn't work for WCFF, what other organic option can work?

Someone from the extension recommended to use REX Lime Sulfur for canker in cherry trees. When and how to apply it? 

Thanks,

Victoria

Hi Victoria, No I recommend GF-120 only for WCFF, it doesn't work for SWD, only for WCFF. If you are targeting SWD the main organic option will be spinosad in a product called Entrust. It must be applied as cherries begin to ripen. If you are targeting WCFF the timing for GF-120 is after the flies emerge. You can use a degree day model to estimate emergence or place traps in your orchard.

More details are available in the Cherry PMG for the Willamette Valley: https://catalog.extension.oregonstate.edu/sites/catalog/files/project/pdf/em8329.pdf

Bacterial canker in cherry is very challenging. If you read the disease management chapter I linked in my first reply, the chemical controls are not very effective. Specifically for lime sulfur it gives the following recommendation:

• Rex Lime Sulfur Solution (28%) at 6 to 12 gal/100 gal water delayed dormant may have some utility. 48-hr reentry.
  

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Hi Victoria,

I'm not sure where you are located. However, I think SWD will be the main concern as this is the case for cherry growers throughout the PNW. If you manage SWD, you likely will not need to worry about WCFF. Yes you would spray whole trees. I would recommend that you obtain a pesticide license, please see: https://www.oregon.gov/ODA/programs/Pesticides/Licensing/Pages/PesticideLicensing.aspx

You will learn how to interpret pesticide labels through the license training including concepts such as REI. REI refers to "restricted entry interval", and is the legally mandated time that entry into the orchard is prohibited after a pesticide application. Even though you may be handing organic products, they are still hazardous to handle and apply. Lime sulfur in particular is highly caustic so please use caution.

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