The story runs that a man was arguing with another, while digging with a mattock on the spot.

As his word was doubted, he became angry, and seizing his mattock he struck the handle into the ground, saying that if  he was not speaking the truth, then the handle would grow.  

And the handle of the mattock grew.  Hence the name.

In 1898 in the columns of the Taunton Courier there was much discussion about a ghost and a toad on Mattock or Maddock Tree Hill

There were tales of a ghost who wandered around near the hill.  It was described thus:

Concerning this hill I have asked several old in habitants of the neighbourhood and Henlade if they could tell me anything about it, but no more than they had heard told by their forefathers.  Peter Starr and another person, who once lived on the top of the hill have related the story, told by another correspondent, to me several times, and have cautioned me in fun of the night to “beware” of the ghost of the woman who had been murdered down the hill a century or more ago!  There must have been some truth respecting the murder.  It is a very dismal part, although there are old houses on the top and bottom of the hill.  I have heard tradesmen of Taunton who attended Chard market weekly tell the same old tale of the hill.

The ghost was a woman dressed in black, and if anyone spoke to her she wouldn’t answer.  If anyone went towards her she vanished.

A correspondent wrote:

I remember and not many years ago, that a toad was found in a stone standing against a gateway near now Stevens’ blacksmith’s shop on the top of Maddock’s Tree Hill.  It was alive, so my informant said, when the stone was broken and jumped about.  It was a great pity that it should have been killed after so long incarceration.  But many people still believe that killing it was the cause of getting rid of the ghost that terrified the neighbourhood so many years.  

And then we come to the toad.  The story goes that a rock was broken open on Mattock Tree Hill and a live toad was found inside.  There are many stories about toads and witches/ghosts.  But there was a belief that if the toad was killed it’s death would make the ghost disappear.

So either the Mattock Tree Hill toad died from the shock of having it’s home destroyed or it was killed by the locals but the outcome was that the ghost disappeared, or so the story goes.

Another commentator added to the story:

A sleeping toad was found in 1872 embedded in the centre of masonry of a wall in North Winfield Church, Derbyshire.  

When the wall was being pulled down it woke up and did the toadyish for stretching and yawning beneath the sympathetic eyes of the Rev JC Cox, the well-known archaeologist, who loves everything old because it is old.  When the beauty had got as wide awake as a toad ever does, and had had a little breakfast, Mr Cox put her into a train and sent her to visit Mr Frank Buckland, a naturalist whose ink stand she promptly converted into a toadstool and dined heartily on raw flies from the end of Mr Buckland’s penholder.  Thence she was sent to the South Kensington Exhibition and the British public craned their necks over one another’s shoulders and admired the beauty.

There must have been a crevice through which she could have crawled into her hold when a mere cradle hunting baby toad and that probably by the time she wanted a change of scene she found that she had grown larger than the door of her room, and so, perforce, became a hermit and lived on the sympathetic flies who came to condole with her on the loss of her liberty.