Hey I'm new to growing fruit but I bought some Gala Apple Trees and planted them in my back yard a few months ago. They were looking great at first and one even has some fruit which made me pretty happy for the first year but now they are getting this yellow leaf thing and I don't know what it is.
I took some detailed pictures because it doesn't resemble anything I've seen online just searching for it. I read a similar problem on here and checked for all the beginner mistakes, water, mulch, low-planting. I think I'm good there but maybe wrong.
Please help.
Looks like a manganese deficiency. 
Get a feed/fertiliser that has manganese in it and scatter on the soil around the tree and water it in.
Could also be worth spraying the leaves with a foliar feed standard tomato feed has manganese in it so should be OK. There may be better or more specific.
Usually yellowing is a sign that the ground is alkaline (chalky) so you may find it easier/better to use a fertiliser for ericaceous plants as that will supply iron as well as manganese.
Get a feed/fertiliser that has manganese in it and scatter on the soil around the tree and water it in.
Could also be worth spraying the leaves with a foliar feed standard tomato feed has manganese in it so should be OK. There may be better or more specific.
Usually yellowing is a sign that the ground is alkaline (chalky) so you may find it easier/better to use a fertiliser for ericaceous plants as that will supply iron as well as manganese.
Second option: The picture I am looking at is similar to yours and says manganese deficency.
The text for both Manganese and Magnesium deficency say yellowing of leaves.
However it seems apples are prone to Magnesium deficency. Sorry to throw in a second option.
However all general purpose fertilisers I have around have both manganese and magnesium in so in theory should help for either situation.
The text for both Manganese and Magnesium deficency say yellowing of leaves.
However it seems apples are prone to Magnesium deficency. Sorry to throw in a second option.
However all general purpose fertilisers I have around have both manganese and magnesium in so in theory should help for either situation.