I feel like a NIMROD
Bill, when you said you had a plain retriever my first instinct was to wonder if it was a lab or spaniel :-)
We have a few trees near our field but they don't give anyone too much trouble. Now the fence at the end of the runway is a different story! We've got pvc on the top wire for easy identification but people still snag it from time to time. One tip a member shared was to watch for the shadow of the plane, when it's passed your hazzard (tree/fence/cow) you should be clear.