Q.Lilac Trees
We have 4 lilac trees along our back fence. Two years ago, one of them became brittle and dead looking and produced no leaves. It is now spreading to the other three. Yesterday I was able to break it off at the ground level or simply pull it up at the ground level. What is happening?

Certified GKH Gardening Expert
The trees are likely infested with some type of insect or have a fungus. You can remove any dying, brittle growth and treat the lilacs with neem oil. It is effective in treating many types of insect pests and is a fungucide as well. Here is more info: https://www.gardeningknowhow.com/plant-problems/pests/pesticides/neem-oil-uses.htm