Ashaya, Soul of the Wild

Ashaya's power and toughness are each equal to the number of lands you control.
Nontoken creatures you control are Forest lands in addition to their other types. (They're still affected by summoning sickness.)

Kalonian Twingrove

Kalonian Twingrove's power and toughness are each equal to the number of Forests you control.
When this creature enters, create a green Treefolk Warrior creature token with "This token's power and toughness are each equal to the number of Forests you control."

Kodama's Reach

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Great Oak Guardian

Flash (You may cast this spell any time you could cast an instant.)
Reach
When this creature enters, creatures target player controls get +2/+2 until end of turn. Untap them.

Heartwood Storyteller

Whenever a player casts a noncreature spell, each of that player's opponents may draw a card.

Orchard Strider

When this creature enters, create two Food tokens. (They're artifacts with "{2}, {T}, Sacrifice this token: You gain 3 life.")
Basic landcycling {1}{G} ({1}{G}, Discard this card: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.)

Rootless Yew

When this creature dies, search your library for a creature card with power or toughness 6 or greater, reveal it, put it into your hand, then shuffle.

Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Burlfist Oak

Whenever you draw a card, this creature gets +2/+2 until end of turn.

Quickbeam, Upstart Ent

Whenever Quickbeam or another Treefolk you control enters, up to two target creatures each get +2/+2 and gain trample until end of turn.

Ghastbark Twins

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
This creature can block an additional creature each combat.

Yedora, Grave Gardener

Whenever another nontoken creature you control dies, you may return it to the battlefield face down under its owner's control. It's a Forest land. (It has no other types or abilities.)

Deadwood Treefolk

Vanishing 3 (This creature enters with three time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)
When this creature enters or leaves the battlefield, return another target creature card from your graveyard to your hand.

Reach of Branches

Create a 2/5 green Treefolk Shaman creature token.
Whenever a Forest you control enters, you may return this card from your graveyard to your hand.

Orchard Warden

Whenever another Treefolk creature you control enters, you may gain life equal to that creature's toughness.

Gnarled Grovestrider

Vigilance
Other creatures you control have vigilance.

Dormant Grove

At the beginning of combat on your turn, put a +1/+1 counter on target creature you control. Then if that creature has toughness 6 or greater, transform this enchantment.

Dormant Grove // Gnarled Grovestrider

Treefolk Harbinger

When this creature enters, you may search your library for a Treefolk or Forest card, reveal it, then shuffle and put that card on top.

Bosk Banneret

Treefolk spells and Shaman spells you cast cost {1} less to cast.

Scurry Oak

Evolve (Whenever a creature you control enters, if that creature has greater power or toughness than this creature, put a +1/+1 counter on this creature.)
Whenever one or more +1/+1 counters are put on this creature, you may create a 1/1 green Squirrel creature token.

Nemata, Grove Guardian

{2}{G}: Create a 1/1 green Saproling creature token.
Sacrifice a Saproling: Saproling creatures get +1/+1 until end of turn.

Kurbis, Harvest Celebrant

Kurbis enters with a number of +1/+1 counters on it equal to the amount of mana spent to cast it.
Remove a +1/+1 counter from Kurbis: Prevent all damage that would be dealt this turn to another target creature with a +1/+1 counter on it.

Kodama of the East Tree

Reach
Whenever another permanent you control enters, if it wasn't put onto the battlefield with this ability, you may put a permanent card with equal or lesser mana value from your hand onto the battlefield.
Partner (You can have two commanders if both have partner.)

Treefolk Mystic

Whenever this creature blocks or becomes blocked by a creature, destroy all Auras attached to that creature.

Verdeloth the Ancient

Kicker {X} (You may pay an additional {X} as you cast this spell.)
Saproling creatures and other Treefolk creatures get +1/+1.
When Verdeloth enters, if it was kicked, create X 1/1 green Saproling creature tokens.

Warden of the Woods

Vigilance (Attacking doesn't cause this creature to tap.)
Whenever this creature becomes the target of a spell or ability an opponent controls, you may draw two cards.

Wickerbough Elder

This creature enters with a -1/-1 counter on it.
{G}, Remove a -1/-1 counter from this creature: Destroy target artifact or enchantment.

Fangorn, Tree Shepherd

Treefolk you control have vigilance.
Whenever one or more Treefolk you control attack, add twice that much {G}.
You don't lose unspent green mana as steps and phases end.

Battlewand Oak

Whenever a Forest you control enters, this creature gets +2/+2 until end of turn.
Whenever you cast a Treefolk spell, this creature gets +2/+2 until end of turn.