Please help identify what is ailing my lilacs!

I recently moved to my property in Chilliwack. There was one existing lilac tree here, and my husband bought me three more last year because he knows how much I love lilacs. Unfortunately this year I got almost no lilacs at all, and the leaves on three of the lilacs (all pretty near each other) have brown spots on them and chunks taken out of the leaves. Does anybody know what is going on with my lilacs and how I can treat them? I'm attaching a photo.

Thanks

 

That looks like Leaf Spot damage. I think there are many different types of fungi that cause this but I think the treatment is generally the same. Open and thin the plant to allow air circulation and light. If you look closely at the leaf spot you can see tiny black dots which are probably the original fungal spores that as the link describes then grow into a larger damaged area. The lack of flowering might be more to do with cold damage than the leaf spot situation.

plant-leaf-spots.htm

 

Yes! There are tiny black dots on some of the leaves. The plants themselves are not overgrown though, as two of them are just babies. Maybe I should just remove all of the affected leaves? I just didn’t want to kill my trees by removing too much! I’ll read the article. Thanks!

 

I don't think it will kill the plant. Just remove any damaged leaves from the plant and from the ground below. Then keep an eye on it especially in the Spring when rains 'splash' the spores from the ground onto the new young foliage.