It is my observation that interdisciplinary courses and team teaching provide a substantial amount of team building, faculty learning, and professional development. As I mentioned, the reward system is vital in driving these kinds of behaviors. If you don't do that, you essentially divorce your desired changes from the existing reward system. You are telling folks that it matters, but not too much. I should also add that I think mathematics leaders should be looking ahead to the substantial opportunities they have to change the culture with the large-scale retirements that are on the horizon.
Most community colleges are about the same age.
Faculty will begin retiring in droves over the next 5-10 years. This represents both a problem and an opportunity. Smart administrators should begin guiding this process in terms of creating the department of the future. If you want interdisciplinary behavior, you should reward and replace faculty on that basis. The message will be clear.