The soil generally has a clay base and the tree is in an open space that gets lots of sun. Wet and dry condition would be reflective of the actual climate conditions for this area (Sudbury). The climate zone I believe is either 2 or 3.
With the apple tree the issue is the fruit. This is a mature tree and we have enjoyed the fruit off this tree for a number of years but the last two or three years the fruit has spoiled on the tree. Although the fruit doesn’t look too bad on the outside, though it is still marked, this inside is definitely affected by something. Again this tree is fertilized by fruit spikes. Although some of the leaves seems to be slightly eaten there are plenty of good foliage on the tree and there is new growth each year.
Any help would be greatly appreciated. Thanks.
Thank you for contacting Toronto Master Gardeners.
From your photo it looks like you have apple maggots. Apple maggots are a big problem for commercial apple growers in Ontario and BC and does require some care to eradicate. In 2014 there was a much higher incidence than previous years which coincides with the beginning of your issues.
Sanitation around the apple tree is an essential first step. Picking up and removing windfall apples helps remove the larvae from the site and will hopefully decrease the number maturing to adulthood. Do not put the apples in your compost, have them removed from your yard.
There are a collection of traps available for catching the adults before they lay their eggs. These can be hung in trees before the adults arrive. Commercial orchards do spray for the larvae but I am uncertain what sprays you will be able to find at your local nurseries available for home use. I have attached two links for sites from the Ontario Government which outline methods to identify and control apple maggots.
Good luck and I hope this information helps.