Is this St Johns Wort, why is the root so big, and how do I remove safely?

Hi everyone,
I hope you are staying safe and well?
We have an area of our garden that is covered in bramble and some green leafy plant.. As we started trying to pull bits of it up, we realised that it is growing from a MASSIVE root system. We used an app on our phone to try and identifiy it, and it is coming out as St Johns wort... but the root is HUGE and we can't really believe it. The roots looked like the roots from the evergreen trees we have surrounding the area. Can anyone help us out and identify the plant / root? Is it safe to just dig out and get rid of? Should I be burning the waste? Any help would be amazing
Thank you in advance, and stay well and stay safe.
Matt

 

It is a Hypericum probably Calycinum I should think ( St john wort is its common name ) . But the root is off the pine tree behind

 

Hi Perki,
Thanks so much for getting back to me. It does look like the Clycinum is growing from the root which really threw me. I won't cut through that huge root though now! I might dig out the Calycinum and try and re-cover some of the pine root system. At least there's time with lockdown. Thanks again. Matt