As long as the hair she donates would be at least ten inches, they do not mandate that they cut it "up to the ears" or anything, and the haircuts are done by professionals.

My very first "real" (as in, not baby sitting or pet sitting) job in the whole world was at an Eva Gabor wig store. We sold mostly synthetics, and had some "real hair" wigs. The "real" ones weighed more than twice as much as the "fakes," and cancer patients usually went with the synthetic both for the comfort and the price. The "real" ones were also much hotter, I was told. For these reasons, I have not donated my mop to Locks of Love, but do support others' choice to do so. I just wouldn't want to inflict a hot, heavy wig on anyone.

Perhaps wig technology has changed, but I haven't heard that. And I usually get it cut before it gets "long enough" anyway.