Oak leaves! Of course (I was thinking in more "southern" trees as olive, palm or laurel
) if your symbols are german inspired! Thanks.
PS: The symbol of the HQ of a logistic brigade is very appealing, but unfortunately I can't understand the meaning. But others are just spectacular (the rangers for example) or very evocative (like the mountain troops).
The symbols are NATO standard, taken from the unclassified allied publication APP-6 NATO JOINT MILITARY SYMBOLOGY. NATO is currently using the APP-6D edition, which I could not easily find, but I did locate the previous version, APP-6C. To my understanding there isn't really many significant changes between the two.