1304 a of unit 1301 and joint 1304 b of unit 1302 to form joint 1304 and is preferably in the center of section 1306 units 1301 and 1302 with pickets 1305 a and 1305 b and section 1306 of fig1 corresponds to second preferred embodiment 200 with pickets 38 a and 38 b and section 28 c in fig6 8 9 10 11 and 12 but of course could also correspond to first preferred embodiment 100 shown in fig1 3 4 and 5 and the corresponding subparts joint 1304 a and 1304 b are configured such that they align together when positioned as shown in fig1 but note that the nature of joint 1304 permits units 1301 and 1302 to rotate in or out in the direction shown by lines 1311 a and 1311 b to make the resulting circular assembly larger or smaller as shown in fig1 17 and 18 or to change direction altogether as shown in fig2 a 21 b and 21 c in order to create the serpentine assembly shown in sections 702 and 704 of fig1 joints 1304 a and 1304 b preferably incorporate the use of two 2 axes 1303 a and 1303 b approximately positioned at locations equidistant from each other and from the outside surfaces 1315 a and 1315 b and interior surfaces 1316 a and 1316 b in other words axis 1303 a and 1303 b are positioned at locations marking one third u2153 of the distance from exterior surfaces 1315 a and 1315 b and interior surfaces 1316 a and 1316 b note the use of the word interior and exterior is mostly for convenience the word interior loosely referring to the interior region of a circular flower bed and.