The bay tree which shades the outside craft spot had sent roots across to the grapefruit tree around the corner of the shed, and sent up suckers. It also went across to the other side, and shot a row of suckers along the front of the shed on the way. So I excavated along the shed base, removing the roots which crossed my path, about 40 cm down.
The blighter had gone well under the shed's concrete base, and I suspected the suckers had gone independent, so I dug under the shed about 15 cm and set slow-burning fire under them. A satisfying number of runners came down from lurking after that.
I replaced soil to the shed edge, then dug the trench, a tad wider than the garden trowel blade, down to almost as deep as the 60 cm heavy black plastic barrier roll (that's on the left, beside the trunk) - removing sections of deeper roots, and rocks. Lined with the plastic up to the grapefruit roots, and put the soil back. (I'll poison any suckers which come up past there.)
Then I dug around the tree, from the shed plastic, in a half-oval, to stop it invading under the house! That area had builders' sand under topsoil and minor roots throughout over compacted limestone rubble which needed clobbering and levering with the stonking great pointed bar (the black thing with a knob on top for hammering, beside the roll of plastic barrier) to shift. The builders' sand and those rocks are the main reason the trench was just the width of the trowel, except where the sides collapsed.
I don't know why there were few major roots in that trench.
I had large piles of sand and dirt, collections of roots, and heaps of rocks before I put in the new liner, glued its ends to the shed liner, and filled the trench - the liner and soil decided the liner was going to undulate, and I didn't argue. Most of the mess has been tidied up, but I'm still not sure what to do with the last of the rocks. Strengthen retaining steps and deepen the gravel paths, probably.
#BayTree #Control #Gardening