Honey, I Shrunk the Orcwort
I second Xarlen's complaint about the Orcwort. The monster is a very cool idea, perfect for a one-evening "The village is being menaced!" kind of adventure. But I think one either has to buff up the little wortlings (to CR12+) or weaken the Orcwort (to CR10 or less).
Here is my attempt at the latter approach:
Lesser Orcwort
Huge Plant
Hit Dice: 10d8 + 50 (95 hp)
Init: +2 (-2 Dex, +4 Improved Initiative)
Speed: 10
AC: 9 (-2 Dex, -2 Size, +3 natural)
Attacks: 6 slams +11 melee
Damage: Slam 2d6+6
Face/Reach: 10 ft. by 10 ft / 15 ft.
Special Attacks: Improved grab, paralysis, swallow whole
Special Qualities: partial immunity to piercing, plant traits, telepathy, woodsense
Saves: Fort +12, Ref +1, Will +6
Abilities: Str 23, Dex 7, Con 21, Int 10, Wis 16, Cha 8
Skills: Hide +5, Move Silently +13
Feats: Improved Initiative
Climate/Terrain: Temperate or warm plains, hills, or marsh
Organization: Crop (1 orcwort + 5-20 wortlings)
Challenge Rating: ??
Treasure: None
Alignment: Always neutral
Advancement: 11-16 HD (Huge); 17-30 HD (Gargantuan)
I've scaled the orcwort down by giving it 10 HD and using the standard size reduction rules. I've also taken away the entangling roots and damage reduction. Paralysis DC is now 20, grappling bonus +21. I'm not sure what the challenge rating on this thing is (I'm not very good at making such judgements). 8 or 9 maybe?