April 2nd Apple IPM message

April 2, 2020

Hi Fruit Growers,

Hope everyone is holding out alright.

I’m happy temperatures cooled down for most of March, though apple green tip occurring before April is never good news.

It looks like we are headed into some wet weather tonight and tomorrow (4/3), potentially causing the first apple scab infection period of the season. We generally don’t worry about these early apple scab infection periods unless an orchard had scab in 2019. I think most RI orchards were free of scab last year.

Temperatures are predicted to be higher next week than this week, and that will encourage bud growth. I think infection periods next week and beyond could cause serious infection periods. The long range forecast looks pretty dry, so perhaps scab won’t be too bad for a while. You can use Cornell’s NEWA program to help make fungicide decisions. http://newa.cornell.edu/index.php?page=apple-diseases
I selected March 30th as McIntosh 50% green tip date in Providence County. Do you think that is accurate?

 If you want help using NEWA let me know and I can help walk you through it.

Now is a good time to apply dormant oil for European red mite and San Jose scale control. 2% oil can be applied from green tip to half inch green, or 1% oil applied at tight cluster. See this link for apple flower bud stages:
https://www.phillyorchards.org/wp-content/uploads/2016/03/apple-bud-growth-stages.jpg
Temperatures are predicted to stay above freezing for the next couple of weeks. You don’t want to apply oil when below freezing temperatures occurred within the previous 48 hours of an oil spray or if freezing temperatures are predicted for 48 hours after spraying.

Jon Clements is planning a Zoom, online meeting on April 8th tentatively at 5:30. I know many of you haven’t experienced an online meeting before. It’s really not so bad! And you and I can have a trial run before April 8th. Let me know if you are interested and we can meet one-on-one online before Jon’s meeting. I hope to have our RIFGA Annual Meeting online in the near future.

I still have permission to make farm visits! And the URI Plant Clinic is open for plant samples. It’s best to drop off samples at the URI Greenhouses at 6 Greenhouse Road. I’ve put a white crate outside the greenhouse door for plant samples and you need to tell me if you are dropping off a sample.

I look forward to talking to you soon! And I’ll send out the link for April 8th Zoom meeting.

Heather