Colonized bugs in trees

[Fifa]

I have found some colonies of some type of flying insect. I have found them in my cedar, elm and pecan trees.
They start out as a "nymph" type insect and grow to an insect with wings. The nymph looks similar to a dwarf pill bug in looks only. They do not have a hard outer covering. They stay together in a group and there are several groups in each tree.
Not much help am I.
I am in the south zone 9.

 

[budroe69moni]

can you post any pictures of these little critters?????? that would help out!!!!
budroe

 

[Fifa]

They have now grown up and flew away. To another tree I imagine to lay some eggs or something. I sprayed the colonies with some pesticide and it killed the ones that were late leaving. I guess I just need to keep an eye on it next spring and get out the camera with the pesticide.
They were very interesting.

 

[John Paul Sanborn]

They were very interesting,

So I killed them.

Sounds like me with sawfly!

 

[Fifa]

Dead Tree

One of my "old" pecan trees is not leafing out. So I guess it's dead. I noticed those bugs in a group on the tree. Just a small colony about as big around as a soccer ball. Is there really a saw fly? By these bugs is a part of the tree that looks like it has been cut in a circle. Are there any type bugs that would eat out part of the tree? :alien:

 

[John Paul Sanborn]

For evry part there is a feeder. Depends on the health of the plant and it's ability to resist.

Saw fly have a neat cattapilar like larva that will rear up when startled. They are a leaf feader.