Cutting back a very large eleaegnus last week, I punctured my wrist on one of the thorns and was reminded of the dangers of gardening.  My wrist instantly swelled up like a balloon, became stiff and painful.  A lot.  Six days later, it is still very brightly bruised but much better.  Eleaegnus thorns are not considered to be toxic and many people won’t even realise that eleagnus even has thorns – it’s one of those sneaky shrubs – like the Robinia tree. I knew, and was careful – respectful even - but was still caught out.   

Thorns can cause serious infections and tissue reactions, especially if they penetrate a joint or tendon sheath, which the larger thorns like eleaegnus and blackthorn can do.  The thorns are  long, strong and very sharp and have a habit of breaking off under the skin and then going septic.  Any such puncture wound allows bacteria to invade and produce a potentially serious infection. This produces obvious pain and swelling because of the inflammatory reaction, which causes inflammation within the synovial cavity.

Blackthorns are often the worst offenders – and lots of first-time foragers don’t realise the risks they are taking when picking sloes at this time of year. Blackthorn (Prunus spinosa) is not considered to be poisonous either but Monty Don describes it as being twice as dangerous as Yew or Laburnum.

It is considered to be bad luck to even bring the blackthorn blossom indoors, because the Crown of Thorns was said to be made from blackthorn.  Apparently Black Rod, who is responsible for the door-knocking in Parliament, is so called because he carries a knocking rod made from blackthorn.

Like other thorny plants, the blackthorn can cause something called ‘plant thorn arthritis’ if a thorn penetrates the skin at a joint – like a/my wrist!  Plant thorn arthritis is the inflammation of a joint caused by a thorn leaving residual matter under the skin, causing swelling, stiffness, pain and sometimes a loss of range of motion.  Whilst having experienced and witnessed numerous ‘plant stabbings’, I haven’t heard it being referred to his before but apparently it is a thing. And I have been a victim.

It’s possible for the symptoms to only become apparent days after the initial puncture, even after the immediate removal of the thorn that caused it – as small fragments left behind by the thorn can cause inflammation to develop days or weeks after. If this is the case, you will need to see a nurse or doctor.

During my treatment, I was told that blackthorn injury can give rise to a wide variety of manifestations ranging from mechanical dermatitis, cellulitis, abscess, foreign body granuloma, peritendinitis, tendinitis, pericapsulitis, synovitis to acute septic arthritis. Synovial tissue is very prone to react to organic substances like the bacteria that is on the tips of thorns like elaeagnus and blackthorn – the tips that are likely to get broke off and stay in the skin or joint.

Now that the hedges are being cut in lanes and along many popular dog walking routes, please be careful when walking your dog too – they can easily pick up thorns, including blackthorns, on their walks and the same symptoms and treatment applies.

There are also numerous other ‘hidden horrors’ in the garden, whilst we are on the subject. I’m running out of space to give them too much ‘credit’ but it is worth looking up Ruta, Hemlock, Euphorbia, Yew, Laburnum, Hogweed and as the name suggest, Deadly Nightshade.

There’s no reason to shun these plants, just be aware of their properties.  Some plants, like  people, are just more anti-social than others.