Yes, more talk about brambles! I am seriously thinking of renaming this blog "All About Brambles" as that's what about half of "new" readers are looking for!
Anyway, another question about brambles which deserves an article to itself, as the first article - the first one of many, by the way - has such a huge list of comments and questions under it, that I bet most people lose the will to live before they reach the end.
So, a new question, a new article.
This one comes from Vicki. (says in Michelle Pfeiffer voice: "Ice skater, or stewardess?") (only joking, I was watching Batman Returns last night!)
Vicki says they have just cleared an area at the back of their garden so they can extend, and that the area was previously covered in brambles.
She asks: "All the shoots are now gone, though, and the
roots are still in the ground. Do you think glyphosate will still help
to kill the roots? We are planning to cover the area with membrane, then
bark chippings: do you think the brambles will still grow through
First question: no, glyphosate will not help at this point, because there are no new leaves for it to be sprayed onto. Glyphosate is a translocated weedkiller, you spray it on the leaves and it moves down inside the plant to the roots, then kills them. So no leaves = no point of ingress. Also, one of the main benefits of glyphosate is that it is inactivated on contact with the soil - it doesn't poison the soil for months afterwards. So by spraying it on bare ground, it is immediately deactivated. It won't penetrate down and kill the roots. (cries of "Drat!" from Vicki)
Second question, will brambles grow back through membrane and bark chips.
Now, this very much depends on how the shoots were removed. If the top inch or two of the area was removed by machinery, ie scraped off, then the growing point will have been removed and all should be well.
But if the shoots were just pulled off, or chopped off using loppers, or a strimmer, they will only have been cut at or slightly above ground level, so the crowns of the brambles are still in the ground. In this case then yes, they will regrow, and they will either grow through the membrane, or they will push it up from underneath, resulting in strange lumpy areas.
My suggestion would be to spray the area with something like SBK, or possibly Pathclear, before you lay the membrane. If you read the instructions for both of those products, you may well be able to decide which one you think fits the bill best.
The non-chemical answer would be to leave the area as it is for a couple of weeks until the brambles start to re-grow, then you can dig them all out properly. (I can hear Vicki groaning from here.)
And the truly eco suggestion would be to get some pigs in to truffle it all up for you, but honestly, that is such a silly suggestion, and I do wish that the dippy hippy eco-warrior brigade would give it a rest: I have only known one person in my entire professional life so far who had sufficient room to put pigs on their bramble infestation: and he refused to do so because it would have taken several months, and he did not want to live with the quagmire they would leave at the end of it, and the smell, noise, disturbance and vigilance they would create and require, in the meantime. *end of annoyed rant*
Hopefully that will answer the question for Vicki!