A year ago I noticed that several of my indian hawthorn shrubs had lost some of their leaves. Close examination showed some partially "eaten" leaves, but I couldn't find any culprits. In early spring I sprayed the plants with and insecticide being sure to cover the underside of the remaining leaves.

I now notice another significant leaf loss. Again it appears some....not a large number...but some leaves have the ends eaten off, but again it isn't a large number.

There are 3 plants like this, yet within 25 feet there are 3 other plants that are perfect.

All plants are well mulched and receive drip irrigation during the growing season. They have been established for 5 years, and are approximately 30" tall and 4' across.

Any suggestions are certainly appreciated.