|“|| "This is some of what you'll use to create the barrier. This part is for you, Stiles-- only you. [...] It's from the Mountain Ash tree, which is believed by many cultures to protect against the supernatural. This office is lined with ash wood, making it difficult for someone like Scott to give me any trouble."|
"Okay, so then what? I just spread this around the whole building and then either Jackson or whoever's controlling him can't cross it?"
"They'll be trapped."
In Teen Wolf, Mountain Ash, also known as Sorbus americana, is a form of ash created by burning the wood from a Mountain Ash tree, which possesses the ability to protect against the supernatural by preventing them from coming into contact with it. It was first introduced in Season 1, when it was revealed that the Druid Emissary Alan Deaton had lined his entire animal clinic with both the wood and the ash to prevent any supernatural clients from doing harm inside, and it has played a significant role in the series ever since. In real world mythology, the wood is often referred to as Rowan and supposedly has the ability to scare off evil beings. In addition to the animal clinic, Eichen House, the McCall House, and the boathouse in the Martin family lake house are all lined with Mountain Ash as well; the former prevents its supernatural inmates from escaping, whereas the latter two are to protect those inside the house from supernatural threats, particularly those who are human.
Its typically used by Druids to not only ward a space against supernatural creatures or create a trap to capture them, but can seemingly also modify behavior as well, according to Alan Deaton; this may explain how he protected himself from Peter Hale's attack on him in Code Breaker and how he forced Kali to shift back into human form in Frayed.Mountain Ash seems to be mystically drawn to itself, allowing any human (including those who utilize supernatural forces such as Druids and Banshees) or unnatural creature (such as Chimeras) to create perfectly formed barriers by throwing the ash into the air; Melissa McCall and Lydia Martin each completed barriers in the McCall House and Martin Lake House, respectively, when they threw the ash and allowed it to fill the gaps in their already-lined homes, while both Marin Morrell and Jennifer Blake created perfect circles of Mountain Ash around them by willing it in a circle and throwing the ash in the air. electrocuted. However, there have been a small number of instances in which a supernatural creature was able to break a barrier, thus allowing them access to the space around it.
In Lunar Ellipse, at the old distillery, the potential True Alpha Scott McCall was able to forcibly dispel the barrier set up by Jennifer using sheer willpower, a feat believed to be impossible; Scott himself has implied that the rush of power from becoming an Alpha from sheer force of will combined with the relatively thin barrier of ash and the life-or-death situation he was in allowed him to do this, and he has yet to replicate this feat since. Another example is Jordan Parrish, who is possessed by the Hellhound, Cerberus, and whose flames are powerful enough to literally burn the mystical aspect of Mountain Ash out of the barriers. In addition to these examples, the Oni have demonstrated an ability to break through Mountain Ash barriers, though it takes time for them to find weak spots that they can exploit, and the Ghost Riders can bypass the effects of Mountain Ash by teleporting in and out of the space within barriers through their power of Atmokinesis.
Strangely enough, Mountain Ash has been shown to have no effect on Chimeras due to their non-supernatural status. They can cross it, hold it, and use it with absolutely no problem, just as normal humans can. In Dreamcatchers, Tracy Stewart, a Werewolf-Kanima Chimera, was able to cross it as if it wasn't even there. Later on, the Werewolf-Werecoyote Chimera, Theo Raeken, was able to hold it and then use it against Scott McCall. Banshees are another being with supernatural powers who can wield Mountain Ash like any other human, as Banshees are technically just human women who channel supernatural forces and use them without being controlled by them as shapeshifters are.
Uses of Mountain Ash
- Marie-Jeanne Valet mixed Mountain Ash with Wolfsbane and added it to steel that was forged with her blood under the light of a Full Moon to create Marie-Jeanne's Pike. ("Maid of Gévaudan")
- At some point prior to the start of the series, Alan Deaton used Mountain Ash to fortify the defenses of his animal clinic by replacing his baseboards and the gate between the reception area and the exam room with rowan wood. ("Code Breaker")
- Stiles Stilinski created a trap at the warehouse rave in order to capture Jackson Whittemore and learn who was controlling him. ("Raving")
- Scott McCall and Alan Deaton created Mountain Ash pills and swapped them out with Gerard Argent's cancer medications to prevent him from achieving his goal of becoming a Werewolf through forcing Derek Hale to give him the Bite and then killing him to become the Alpha. ("Fury"), ("Master Plan")
- Marin Morrell created a barrier inside First National Bank's vault to force Scott McCall and Derek Hale to fight the rabid Vernon Boyd and Cora Hale. Allison Argent broke the barrier shortly afterward, inadvertently freeing Boyd and Cora in the name of saving the lives of Derek and Scott. ("Chaos Rising")
- The Darach used Mountain Ash to create a barrier to prevent anyone from reaching Alan Deaton, her intended "healer" sacrifice, though this barrier was ultimately and unknowingly broken with the help of Sheriff Stilinski. ("Currents")
- Marin Morrell created a barrier to prevent herself from being harmed by Deucalion, Kali, Ethan and Aiden, though it was unable to protect her from Deucalion throwing his blade-tipped cane through her shoulder. ("Alpha Pact")
- Jennifer Blake created a ring of Mountain Ash to protect her from Scott McCall, Derek Hale, and Deucalion. This barrier was ultimately broken by Scott during his ascension to True Alpha status. ("Lunar Ellipse")
- The Calavera Family hid the Triskelion Urn in a box made of rowan wood and filled with Mountain Ash to prevent Derek Hale and Peter Hale (or any other supernatural creature) from getting inside of it. ("More Bad Than Good"
- Melissa McCall created a barrier at the McCall House to prevent the Oni from coming in and attacking Rafael McCall, Scott McCall, Derek Hale, Kira Yukimura, the twins, and herself, though the Oni were eventually able to break through it by exploiting the barrier's weak spots with their ninjatos. ("Galvanize")
- The barrier also confirmed Kira's status as a supernatural Thunder Kitsune when she was unable to cross it.
- The Chemist created a barrier in his laboratory to trap the Werewolf test subject who was exposed to and killed by the Modified Canine Distemper Virus he created. ("Weaponized")
- Alan Deaton tossed a jar of Mountain Ash at the doorway to the exam room of the Beacon Hills Animal Clinic in order to complete the room's built-in barrier and to prevent Tracy Stewart, whom they believed to be a newly-turned Werewolf, from leaving. However, this barrier ultimately proved to be useless as a prison due to the fact that Tracy was actually a Werewolf-Kanima Chimera and thus immune to the effects of the substance. ("Dreamcatchers")
- Scott McCall and Kira Yukimura were sedated and somewhat weakened from being in the vicinity in the thick and powerful Mountain Ash barriers outside of the closed supernatural unit of Eichen House while Stiles Stilinski and Lydia Martin questioned Eichen House prisoner Gabriel Valack regarding the Dread Doctors. ("A Novel Approach")
- Theo Raeken made a barrier in Beacon Hills High School to trap Scott McCall and Liam Dunbar with the intention of having Liam kill Scott, revealing his own Werewolf-Werecoyote Chimera nature. This barrier was later broken by Mason Hewitt just before Liam had the chance to kill Scott. ("Status Asthmaticus")
- Scott McCall and Liam Dunbar found themselves unable to pass a thick barrier of rowan wood and mountain ash while trying to rescue Lydia Martin from Eichen House. ("Lie Ability")
- Melissa McCall and Braeden created a series of barriers at the McCall House to protect Malia Tate from her mother, Corinne. The final barrier was broken by the Werewolf-Kanima Chimera Tracy Stewart, who had been asked by Theo Raeken to assist Corinne as part of their agreement. The barrier was then restored by the mercenary Braeden, trapping Malia and Corinne inside the house. ("The Beast of Beacon Hills"), ("Apotheosis")
- Mason Hewitt and Corey Bryant created a barrier of Mountain Ash to prevent the Ghost Riders from coming to capture and erase Gwen from reality during a party at the McCall House. It was then revealed that the Ghost Riders could bypass the effects of the Mountain Ash by using their atmokinetic teleportation to transport themselves inside and outside of the barriers by riding the lightning. ("Sundowning")
- Stiles Stilinski, on Scott McCall's instructions, stole Mountain Ash from the Argent Arms International armory and brought it to the high school, where he used it to create a barrier around the Anuk-ite to use its power of Petrification against itself, defeating it and saving Peter Hale, Malia Tate, Derek Hale, Jackson Whittemore, and Ethan Steiner from death. ("The Wolves of War")
- In large and potent quantities, Mountain Ash can even weaken a supernatural creature who is in its presence, as Scott McCall and Kira Yukimura both stated that standing outside of the heavily-fortified supernatural ward of Eichen House was making them feel weak and sedated.
- Mountain Ash has no effect on humans, Banshees, or Chimeras.
- Malia Tate referred to her first experience with mountain ash as "weird."