Any ground-covering vegetation in the spells area
becomes very hard and sharply pointed without changing its
appearance. In areas of bare earth, roots and rootlets act in the
same way. Typically, spike growth can be cast in any outdoor
setting except open water, ice, heavy snow, sandy desert, or bare
stone. Any creature moving on foot into or through the
spells area takes 1d4 points of damage for each 5 feet of
movement through the spiked area.
Any creature who sustains damage from this spell must also
succeed at a Reflex save or suffer injuries to its feet and legs
that slow its speed by one-third. This speed penalty lasts for 24
hours or until the injured creature receives a cure spell (which
also restores lost hit points). Another character can remove the
penalty by taking 10 minutes to dress the injuries and succeeding
at a Heal check against the spells save DC.
Spike growth is a magic trap that cant be disabled with
the Disable Device skill.