Cedar Apple Rust.
Take a look at Spectracide Immunox for next year.
Spray after petal fall.

Thanks megamav, I'm gonna stay with organic controls--it may be on last legs anyway, but if it can't make it without chemicals I need a different variety. Arborvitaes are the only cedar relatives nearby, and they don't show any signs.

I also use Immunox. However, if you want to try something else, you can try wettable sulfur spray. It may work.

I don't mind spraying Immunox because I only spray twice, once at petal fall and the second time 2 weeks later. After that, it's time to bag apples with plastic bags.

My Honey Crisp has some CAR later. My William's Pride is not really get any CAR.

If you really want to go organic, you need to start with disease resistant apple varieties. Luckily, there are a number of them.

They may not show signs now because the cedar galls have fallen off the tree. This disease cycle starts in the early spring, when its wet.

Its also possible the spores have traveled in from up to a mile away.

The only true avoidance is to spray at the right time.
Even "resistant" varieties are not immune to large outbreaks.

I do 2 sprays of Immunox in the spring after petal fall and 2 weeks after, and my trees dont show anything.
A neighbor 3 doors down has Winesap and Red Delicious and they're covered in CAR and Scab.

Just remember, organic material (copper, sulfur) doesnt mean its not dangerous.
The chemicals I've sprayed are off the tree by now with rain.

Are you a certified organic orchard?

This post was edited by megamav on Fri, Aug 16, 13 at 18:34

your tree will probably be back next year, but won't fruit, but just baby it along and it will get there. I have posted this in a few other threads recently. baking soda in water. in a bottle sprayer a couple tea spoons, in a gallon size sprayer half a cup. rain will wash it off so remember to respray. Lots more to learn about growing apples. you nedd to understand the pests that will hit the fruit when you get that far. (squirrels are #1 if you are in the city) I don't know about sweet 16, but there are apples that are better then others for organic. you might look at this thread and do some other searching

Here is a link that might be useful: another thread

The CAR fungus requires two hosts, apple and eastern red cedar (Juniperus virginiana L.)