I have 2 flowering crabapple trees. Both appear distressed but look...
I have 2 flowering crabapple trees. Both appear distressed but look different. One ("snowdrift") is losing leaves from the lower branches. Most leaves have dark bron/black spots. The other tree has unusually small leaves this year, but is not losing them.
Ramsey County Minnesota
The tree that is losing leaves probably has Apple Scab. It is a fungus. It is too late to treat for it this season but sanitation will be extremely important. Pick up and remove all fallen leaves to help prevent the fungi from staying in the soil around the tree to be distributed again next spring. You can use a systemic fungicide very early next spring to help prevent it. The fungicide will not harm pollinators. As far as the small leaves, many trees had a hard time surviving the harsh winter and some leafed out very thinly or with smaller leaves. Give your tree TLC this year and hopefully it will look better next year.