How do I take care of an oak tree?

Mary I would check your local cooperative extensions for these answers. You can check the web for your growing zone.

MIf it’s the 50’s and it’s an outdoor tree to begin with I’d set it out for a bit at a time so it isn’t shocked.

I guess I am not sure what you are asking. I live in Michigan and have oak trees in my yard. They have been there for years ( some 70 + years) at temperatures from the high 90's to -20 degrees below zero.

Transplanting is okay as long as the sap is down. We usually do it in February but my husband has plants thousands of trees in the winter in zone 7b. Here is an article that might help you.

http://bountifulharvesting.com/index.php/2016/10/13/transplanting-an-oak-tree/