On one boundary of Dulwich Wood is a Cherry Laurel hedge separating it from a quiet cul-de-sac and on the outside of the hedge is a strip of grass verge. At the edge of this verge a tiny yellow flower has appeared this week.
I’m pretty sure this is Trailing St John’s-wort Hypericum humifusum which Rose’s guide says is common on heaths and in open acid woodland. So why’s it here? Are the road materials creating an acidic verge? [Some more expert botanists fed back after I’d posted this that they thought this plant was more likely to be Hypericum perforatum or Perforate St John’s-wort]
I do something I wouldn’t do in any other circumstance… I dig a little piece of the plant up, roots and all. Why? Because the local contractors are here this week and probably any day now they’ll weed it out.
I post a picture on Twitter and ask the botanists if they agree with my ID. I receive a few non-committal likes but I’m still optimistic.
I check on the Botanical Society of Britain and Ireland’s website and see that there hasn’t been a record of this plant in this tetrad or 2km by 2km square TQ37 since 2010 and only one in the previous decade. Note to self, must find out how to submit a record, even if it isn’t appropriate for this one.
In the meantime I’m going to do what I can to make a pressed “voucher specimen” and as H. humifusum is perennial, I’m going to plant what’s left of my sample in a tub along with a few other weeds I’ve rescued.