List Generic - get some files

Question

I created a generic string list, in which I want to add files from two different locations: from C:\folder1 and from C:\folder2. The files that I want to add, have .pdf extension and as comparation, must be accessed today. This is my code:

List<string> PDFiles = Directory.GetFiles("C:\folder1\", "*.pdf", SearchOption.AllDirectories).Where(x => File.GetLastAccessTime(x).Date.ToShortDateString() == DateTime.Today.Date.ToShortDateString())

                                                  .Select(x => x)

                                                  .ToList();

Now how can I add the next files, from C:\folder2 path? (with the same extension and comparation )?

I tried something like this, but I don't know if is such a good idea:

 foreach (var test in Directory.GetFiles("C:\folder2\, "*.pdf", SearchOption.AllDirectories).Where(x => File.GetLastAccessTime(x).Date.ToShortDateString() == DateTime.Today.Date.ToShortDateString()))

                {

                    PDFiles.Add(test);

                }