Can yoiu please identify the species of tree. it is very difficult to tell from the photo. It would be helpful if you could take a photo of the whole tree.

See photo of tree

See photo of tree

It is hard to identify without seeing a whole leaf but believe it is a hawthorn. This plant is susceptible to rust disease which can be seen on the leaves. It can live with this disease which causes the orange to yellow spots on leaves and it can also infect the fruit. It is unique in that it starts on a juniper which gives it the name cedar-apple-hawthorn rust. Treating would require proactive sprays to the leaves prior to the disease starting in the spring. Fungicides can be applied just as flower buds begin to swell but before they open. Usually requires multiple treatments to get it past the stage where it is active on the junipers. Does not harm the junipers. For more information see the following: https://hortnews.extension.iastate.edu/cedar-hawthorn-rust

Thank You!!

You are welcome!  Have a great day!