That's really interesting.

    The RF shielded group evidenced more vigorous growth,
    producing 74% more total leader length and 60% more leaf 
    area than the mock-shielded group, though the number of 
    leaves produced by both groups was nearly the same.

And

    Leaves on active leaders in the shielded group were 
    substantially free of leaf tissue lesions (Figure 7), but 
    unshielded and mock-shielded leaves were all affected to 
    some extent by leaf tissue necrosis (Figure 8)

Would be nice if they had analyzed the spectrum to identify roughly what frequencies/equipment this area is exposed to.

Just like in the electronics-on-airplanes issue, it concerns and wonders me that there isn't more research being done in such basic areas.