Source:dota2.gamepedia.com/Trees

Trees

Trees are a terrain feature in Dota 2. They make up a large amount of the map, and are very prominent in the forests that separate the Lanes and border the map. Trees block vision and are impassable.

Mechanics

Trees cannot be targeted by normal attacks, and can only be destroyed by certain skills, such as Beastmaster's Wild Axes.
Trees will regrow five minutes after they were destroyed except if a Hero is standing where they would spawn.
There are 2662 trees in the Dota 2 map.

Abilities that Interact with Trees

Abilities that Destroy Trees

Batrider - Firefly Destroys all trees Batrider flies over.	Batrider - Flamebreak Destroys trees units are pushed into.
Beastmaster - Wild Axes Range: 1300 Radius: 125	Dark Seer - Vacuum Radius: 250/350/450/550
Elder Titan - Earth Splitter Area: 300 (width) / 2400 (distance)	Enigma - Midnight Pulse Radius: 400
Force Staff - Force 2250 Range: 600	Invoker - Deafening Blast Destroys trees units are pushed into.
Io - Tether Radius: 300 Only destroys trees if cast from over 700 units away.	Jakiro - Macropyre Range: 900 (1350*) Radius: 225
Lina - Light Strike Array Radius: 225	Leshrac - Split Earth Radius: 150/175/200/225
Magnus - Skewer Range: 600/800/1000/1200 Radius: 125	Nature's Prophet - Nature's Call Radius: 150/225/300/375
Phoenix - Sun Ray Destroys all trees Phoenix flies over.	Quelling Blade - Destroy Tree 225
Rubick - Telekinesis Radius: 325	Spirit Breaker - Greater Bash Destroys trees units are pushed into.
Storm Spirit - Ball Lightning Range: Global Radius: 125/200/275	Slark - Pounce Destroys trees in a 200x200 square around Slark's landing area.
Tango - Eat Tree 125	Timbersaw - Chakram Range: 1200 Radius: 200 Chakram automatically returns after Timbersaw moves 2000 units away.
Timbersaw - Timber Chain	Timbersaw - Whirling Death Radius: 300
Tiny - Toss Radius: 275	Tusk - Ice Shards Radius: 300
Tusk - Snowball Range: 1250 Radius: 200 + 40 per sec	Vengeful Spirit - Nether Swap Range: 600/900/1200
Warlock - Chaotic Offering Radius: 600	Windrunner - Powershot Range: 1825