Wood Wood was an organic material deriving from tree s . This was a widely - known fact . ( TV : " City of Death " ) " Woods " was also a word used to describe forest s , spaces with large quantities of trees . Wood would catch fire under extreme heat . ( TV : " The End of the World " ) Some objects that were made of wood , such as cricket bat s , required regular application of linseed oil for proper maintenance . ( TV : " Castrovalva " ) Beaver s could chew through wood . ( PROSE : " Wetworld " ) The Doctor ' s sonic screwdriver was ineffective on wood . He was rather embarrassed of this . ( PROSE : " Catastrophea " , TV : " Silence in the Library " , " The Hungry Earth " ) Once , when the Eleventh Doctor was battling Androzani tree s , he complained about the alien s being made of wood , rendering his sonic useless on them . ( TV : " The Doctor , the Widow and the Wardrobe " ) He again found himself in this predicament when facing peg dolls , and noted that he meant to add this setting . ( TV : " Night Terrors " ) The Twelfth Doctor moaned that he still had not added a setting for wood . ( TV : " Empress of Mars " ) When trapped in the Tower of London in 1562 , the War Doctor devised a plan whereby his sonic screwdriver could disintegrate the wooden door , using the added processing power of the Tenth and Eleventh Doctor ' s sonic screwdrivers , running a program for hundreds of years . The problem was solved , but application of the solution was interrupted when Clara Oswald walked in through the unlocked door . ( TV : " The Day of the Doctor " ) Many of his companion s ridiculed the Doctor for his TARDIS exterior being seemingly made of wood . ( TV : " Smith and Jones " , " Meanwhile in the TARDIS " , " The Bells of Saint John " , " The Pilot " ) Uses . Wood was often used to start and / or maintain fire s either in a fire pit ( TV : " Countrycide " , " The Sound of Drums " ) or in a fireplace . ( TV : " The Girl in the Fireplace " ) Book s , gallows and spoon s were all made from wood . ( TV : " Silence in the Library " , " Mona Lisa ' s Revenge " ) Door s were also made from wood . ( TV : " Silence in the Library " , " The Hungry Earth " ) One of Banquo Manor ' s doors were described as having been made of " strong wood . " ( PROSE : " The Banquo Legacy " ) Centuripede s required oak wood to build a pod to transport their egg s . ( TV : " The Last Oak Tree " ) The Dalek s had wood used as support beams in the mines dug by their human slave s during their invasion of Earth in the 22nd century . Ian Chesterton jammed the Daleks ' bomb in its shaft with some left - over support beams , ultimately resulting in the destruction of the entire Dalek invasion force . ( TV : " The Dalek Invasion of Earth " ) A wooden Cyberman was used during the Siege of Trenzalore in an attempt to bypass the Papal Mainframe ' s force field . The plan nearly succeeded since the Cyberman was low - tech but the Eleventh Doctor used his sonic screwdriver to send a signal which would have reversed the polarity of the Cyberman ' s weapon causing it to fire backwards . The Cyberman turned its weapon around and shot itself , since the Doctor did not mention the screwdriver did not work on wood . ( TV : " The Time of the Doctor " ) When Amy Pond asked if a door would keep Prisoner Zero at bay , the Eleventh Doctor sarcastically retorted , " It ' s an alien multi - form from outer space ; they ' re all terrified of wood ! " ( TV : " The Eleventh Hour " )