In a way yes, because if you join the National Guard you Can Not apply for the National ROTC Scholarship or compete for a Battalion Scholarship once on campus.
The only Scholarship you can apply for is the GRFD, which if you get requires you to remain in the Reserves/National Guard when you commission, you would not be allowed to compete for Active Duty if you accept the GRFD Scholarship.
If you apply for the National ROTC Scholarship, join the Guard, you may be able to get a release from the Guard if you are awarded a Scholarship, you can't do both unless it's a GRFD Scholarship.
You really need to talk to a Recruiting Officer at an Army ROTC Battalion before you sign anything with the Guard. Do Not go by just what your local recruiter tells you, their job is to get you to enlist, they do not know all the in's and out's of the ROTC program and it has and is changing a lot right now so make sure you talk with a ROTC Battalion before you do anything. Research the ROTC SMP Program fully before you sign anything. The SMP program is changing as well, if your interested in Active Duty at all, do more research.