Are the bumps small scaly brown bumps? If so, you probably have a scale infestation. Horticultural oil or certain insecticides are used to treat this.

If that doesn't appear to be the problem, posting a picture might get you a more accurate diagnosis.

Possibly lilac blight.

Lilac leaf miner. Search "lilac problems" or similar phrases. Or try Kansas Cooperative Extension Service for diagnostic assistance.

I didn't know that lilac even got blight. I had to treat spring snow crabapple tree last year for something similar. Our extension office send out quarterly newsletters which has a nice section on trees but mine is not commonly grown in this area. I will check out some of yours suggestions.

Thanks

Lilac blight also affects magnolias. Search Pseudomonas syringae. The species name is after Syringa, the genus of lilacs.

So, yes, lilacs get a blight.

One oversized garden center/growing operation I worked at here was watering the potted lilac sales area with overhead sprinklers when it stared to warm up in spring. The common lilac cultivars seemed to hold up under this OK but the new growth on the tree lilacs came out and then blighted off badly. I am sure it was the overhead dousing.

Lilac blight doesn't cause bumps on the leaves. It can cause malformed leaves and usually causes black/brown areas on the leaves. Again, a picture or more details are necessary to diagnose a problem like this.

Brandon7, your right, that's why I went outside and collected some leaves. I examined and compared the leaves to pictures I saw online. I'm almost 90% sure its blight and due to rain being in the forecast for the next several weeks, treating it will be a problem. So I have emailed the Johnson county extension office for advice.

Brandon7 and bboy just came back from the extension office while it does look like blight, its not. Turns out due the early warm up in late February the leaves on the tree came out early. We then had two late freezes in late March and about the second week in April. It didn't seem to affect any thing except the early blooming flowers and it seems the leaves on this tree. So I guess its freeze burn not sure if that's the right word. Hopefully in a few weeks there will be some leaves but it might not bloom.

One thing I did find interesting is out of the three people in the office only one even knew about lilac trees. They're just not common in our area.

Mu leaves are very small with not to many blooms on a three year old lilac. What do you think is the problem?

Considering this thread is almost a decade and a half old, you'd get better responses by starting you own thread, adding some pictures of your plant and giving us some background information, what part of the world you are in, time of year there and what the weather conditions have been for the last several months.

Other than that, a 3 year old tree lilac (syringa reticulata) may not be mature enough yet to bloom.

Thanks!

Thanks for your quick response. I live in Michigan, an hour north of Detroit. No visible signs of blight or disease. The Japanese lilac DID have some blooms this year.

How small are the leaves? Any late frosts that might have affected them?

Without pictures, it's very hard to envision anything just staring at my computer...