Cedar apple rust. Gold Rush is pretty disease resistant, but definitely susceptible to CAR. Mine gets it every year, but not enough to spray… yet.
Definitely Cedar apple rust. I have it also on my newly planted Gold Rush and one year old Golden Delicious. Apparently the organic sprays of sulfur did not work.
I have been completely organic up to this point, but am willing to spray those two trees with a fungicide next year if it means having Gold Rush apples. Removing all the cedar trees around is not possible for me.
Would Captan work? It’s the only fungicide I have on hand.
I’m pretty sure it is too late to spray or do anything about. I think you have to spray at petal drop, but that could be wrong. You will get funky looking orange blobs growing from the leaves. That is the fungus going through its life cycle. I don’t think it will infect new leaves that continue to push out.
Gold Rush is very susceptible to CAR.
It’s a first year tree - I am concerned it will affect vigor.
I can’t even think of any junipers nearby.
I sprayed with Pristine (in Bonide Fruit Tree and Plant Guard) in late June or early July last year and I swear it killed the the CAR that developed on my newly grafted Goldrush tree. I think that it killed it because the spots turned brown and the tree kept the infected leaves all season.
My Goldrush graft was the most vigorous of all my grafts last year and it grew about 2.5’ in a season.
Hmmm, thanks for correcting me. I thought that once the spots appeared the infection had happened. How did the graft do this year?
My Gold Rush gets a little CAR but not as bad as my crab trees. As of now the tree seems to deal with it.
I use Immunox. It will stop the development of the cysts, but you’ll be left with dots of damage.
Captan is used on apples to help control scab primarily, it has little effect on CAR. Myclobutanil and others in its class are amazingly effective but pressure varies a great deal season to season- mostly depending on how wet it is as with most fungus issues. Before there were sterol inhibitor fungicides products like Mancozeb were used which wash off in the rain and have no kick back.