Is this Apple Scab?

Hi,

I have a 3.5 year old apple tree and last year a lot of its leaves went brown and crispy and fell. I assumed that I had been underwatering.

This year I have been very diligent with watering, perhaps even going overboard. However I am starting to notice the same. On closer inspection I can see that there are some dark spots and yellow areas, before they get brown and completely crispy.

Having looked at it online, I suspect that it is apple scab. Would you agree? I plan to spray with copper fungicide. I believe it is recommended not to eat the apples on a year that you use fungicide, even if it's not synthetic. Is this correct?

Thank you.

 

It probably is scab.
I don't think there's much you can do that will prevent it other than clearing up fallen leaves and infected apples to try and reduce the infection the following year.
You can try a copper-based spray.
Bordeaux Mixture is the one that used to be used when I was a lad. It's easy to mix and recipes on the web.
It is not a systemic fungicide, so the fruit can be eaten if it's been applied properly.
Usually give the tree a drench around Nov and again just before the flowers open and that should be enough.
But....if there are infected trees in neighbouring gardens it may well still spread to your tree too and infect it even after spraying.
One of my 3 apple trees seem to have it this year.

I've not used Bordeaux Mixture (or any other copper-based treatment) since I was a lad so have no recent experience of its effectiveness.

 

Thank you @Pete8

I have already ordered a different brand of liquid copper fungicide. I will check the instructions but I am happy to sacrifice this year's crop for the sake of the health issuebof the tree itself, as it seems that it's going to lose a lot of leaves (it's a dwarf tree anyway so we are not talking about a huge amount of apples).

 

Just take note that a lot of copper based products are not officially available for non commercial growing in the UK (if you're based here, that is) of course lots of unscrupulous sellers provide them online, anyway.

 

Thank you, good to know. Yes, I live in tye UK. The product I ordered has good reviews and some of them mention apple scab specifically (Liquid Copper Fungicide Pint 16oz https://amzn.eu/d/075UvOzW)

 

It's an American product that presumably hasn't been fully authorised for use in the UK...but here we are, still for sale.

 

There's nothing 'wrong' about using copper-based fungicides, especially for home gardeners.

e.g. Bordeaux Mixture was banned a long time ago, but that was because fruit growers used it frequently each year in their orchards as a preventative.
Over years this causes a build up of copper in the soil which can eventually become toxic.
If the copper then washes into a river then it can devastate aquatic life.

But a gardener using it maybe couple of times a year if necessary is not going to have any detrimental effect - unless I guess you have a river running close by your trees.

 

All I said was what the regulation is currently. Run off to water courses is the main issue... admittedly with them currently being full of untreated sewage it's a bit more difficult to get people to think of consequences of these products. Times move on while trying to be a bit environmentally friendly whenever possible.

 

Thanks both, that's really useful information. Luckily I don't have a river close to me, or drainage near the tree. I definitely don't plan to be using this systemically, I just want to give it a couple of applications because I have read that apple scab can severely weaken a tree after consecutive years and increase the chances of it dying over winter.