  Future direct observations of extrasolar Earth-sized planets in the habitable
zone could be hampered by a worrisome source of noise, starlight-reflecting
exozodiacal dust. Mid-infrared surveys are currently underway to constrain the
amount of exozodiacal dust in the habitable zones around nearby stars. However,
at visible wavelengths another source of dust, invisible to these surveys, may
dominate over exozodiacal dust. For systems observed near edge-on, a cloud of
dust with face-on optical depth 10^-7 beyond ~5 AU can mimic the surface
brightness of a cloud of exozodiacal dust with equal optical depth if the dust
grains are sufficiently forward-scattering. We posit that dust migrating inward
from cold debris belts via Poynting-Robertson drag could produce this
"pseudo-zodiacal" effect, potentially making it ~50% as common as exozodiacal
clouds. We place constraints on the disk radii and scattering phase function
required to produce the effect.
