Mostly Spikes.
Brambles spell read:
Small magical thorns or spikes protude from the surface of a wooden weapon, such as a club, greatclub, nunchaku or quarterstaff. For the duration of the spell the weapon deals both piercing and bludgeoning damage. It gains a +1 enhancement bonus on its attacks and deals an additional +1 point of damage per caster level (maximum +10). This spell works only on melee weapons with wooden striking surfaces. For instance, it does not work on a bow, an arrow or a metal mace.
Well... It gains thorns or spikes!
So, the Spike spell reads:
As Brambles, except that the affected weapon gains a +2 enchanment bonus on its attack, and its threat range is doubled.
Meh-.. Wait. Threat range is doubled? Where is the part, that normaly says "Does not stack with Keen, Impact and Imp. Crit" ?
Has this been errated - if not.. yum!
Both spells are from Complete Divine.
Brambles is a Cleric and Druid level 2 spell, while Spikes is a Cleric and Druid 3.
Also, is there any way one can change the parameters of the bramble spell, to work on metal weapons?
If not, what kind of sexy wood-weapons is out there, that we can enjoy?