"Early practitioners of dark witchcraft favoured the wood cut from Blackthorn and tipped with the thorns as a wand – or even as a ‘blasting rod’ or ‘black rod’, used apparently for cursing. The rod would frequently have the ancient Futhark rune for thorn ‘Thurisaz’ scratched or burned into it.The thorns have been found stuck into witches ‘poppets’, used as pins. Superstition tells us that the devil pricked the fingers of his victims with a sloe thorn and sealed the deals he made in the resulting blood. Because a scratch from the sloe bush was apt to go septic if unattended, it was thought to be poisonous.Witches burned as heretics were sometimes accompanied into the fire with their blackthorn wands or staffs, and branches of it were thrown in to feed the flames. This may be where the tree gained its reputation for purification, and even exorcism.The starry blossoms were considered unlucky and not worn as a decoration or brought into the house. They were associated with death, probably because they bloom on the bare, thorny black branches at winter’s end"
"The Blackthorn is depicted in many fairytales throughout Europe as a tree of ill omen. Called Straif in the Ogham, this tree has the most sinister reputation in Celtic tree lore. The English word “strife” is said to derive from this Celtic word. To Witches, it often represents the dark side of the Craft. It is a sacred tree to the Dark, or Crone aspect of the Triple Goddess, and represents the Waning and Dark Moons. Blackthorn is known as “the increaser and keeper of dark secrets”. The tree is linked with warfare, wounding and death, associated with the Cailleach - the Crone of Death, and the Irish Morrigan. Winter begins when the Cailleach (also the Goddess of Winter) strikes the ground with her Blackthorn staff"
"The Blackthorn has a long and often sinister history, associated with witchcraft and murder, but it is also associated with the concept of the cycle of life and death and protection not to mention its practical physical uses. It is often associated with darkness, winter, and the waning or dark moon, a particularly cold spring is referred to as 'a Blackthorn winter'. The devil was said to prick the fingers of his followers with Blackthorn to seal their pact. It is considered the opposite of the benign Hawthorn (which is also known as Whitethorn) with which it so frequently grows. The Blackthorns spines are extremely hard and can cause a great deal of bleeding, and the wound will often turn septic. They were frequently used as pins by English witches and became known as the 'pin of slumber'. The shrub was denounced as a witch’s tool by the church and therefore the wood of the Blackthorn was used for the pyres of witches and heretics. They were also placed under horse’s saddles, by the rider’s enemies, causing the horse to throw its rider when the spines pieced the horses flesh, causing injury or death to the unfortunate rider.
The Blackthorn is also seen as a protective tree and representative of the endless cycle of life and death. For all its deadly associations the blossoms were used in ancient fertility rites as well as being hung in the bedchamber of a bride on her wedding night. It provides blossom whilst there is still snow on the ground while everything else still seems dead from its winter sleep, its dense branches protect the year’s new chicks from predation and in their adulthood provides them with food when many other species of plant have lost their berries. It is a thicket of these trees that protects sleeping beauty in her castle, and witches in northern England would carve the symbol for thorn on a Blackthorn staff for protection.
The tree itself is said to be protected by the fairy folk. It is considered a fairy tree and is protected by the Lunantishee, a type of fairy that inhabits it. They will not allow a mortal to cut Blackthorn on May 11th or Nov 11th (said to have been the originaldates of Beltaine (May Day) and Samhain (All Hallows Eve) before the calendar was changed. Great misfortune will befall anyone who ignores this advice. The Lunantishee may also be the Leannán Sidhe or Fairy Lover"