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

I believe that's lichen or moss. I doubt it's the reason for your sickly apples. Check out videos by Stephen Hayes on youtube. He is based in the UK and has some great videos about rehabilitating old apple trees there. His trees look a lot like yours.

Cedar- apple rust? Just a guess since I have never had it (luckily). Spray with myclobutanil (Rally, Nova, or Immunox fungicide) early in the season. For me that means 2 applications in May and I never have the problem. Do you lots of eastern redcedars growing nearby?

the goo is gumosis ....a systemic problem that is not correctable ... and will lead to the trees demise ... which in tree time.. might be 5 or 10 years ... who knows ... https://duckduckgo.com/?q=gumosis&t=ffcm&ia=web the leaf issue reminds me of japanese beetles ... but you would have to find the bug for complete ID ... and it might be long gone.. since i see unaffected leaves ... where are you.. big city name ... isnt this a deciduous tree ... and it will soon be losing its leaves ... so who cares if they fall off ugly ... it is tree planting time for most of us.... perhaps its time to plant a new tree or two.. and plan on getting rid of this one due to the disease .... ken https://sites.google.com/site/tnarboretum/Home/planting-a-tree-or-shrub