Question
QUESTION: i am in az 40 years i have always noticed on scrub oak trees and i belive all species of oak except gamble oak a nearly hollow bulb type growth with a seed type object suspended in the center being supported by very fine "hairs" the bulb can get up to about 2" in diameter most all bulbs found have a hole in them looks like a bug chewed its way in

ANSWER: These are insect galls. A tiny insect lays its eggs either on the surface of a leaf or on a twig and secrete a chemical that causes the cells of the plant to expand and cover the eggs. The eggs hatch and mature and bore out of the gall. The hole is where they come out not enter.These cause little heath problems to the tree and need not be treated. The population of these insects will vary each year depending on the weather so some years there will be large numbers other years very little galls are seen. Not a real problem to the tree.

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QUESTION: can you tell me what these insects are named? and maybe send a pic of one? also are there more than one species?

Answer
There are several different kinds and species depending on the size and looks of the galls. here is a web link that describes some of these. It really does not matter which one you have except for conversation sake--none need treatment.

http://ento.psu.edu/extension/factsheets/galls-oak