I recently walked the Cape to Cape track, starting at Cape Leeuwin, on 21.10.2011. A notice there, with photograph, advised of an invasive thistle that should be reported if seen along the track. On 26.10.2011, at Bob's Hollow,about 40 or 50m Nth of the metal trapdoor,near the cave,I saw what I believe were a small number of these thistles, some flowering, beside, and mostly on the Sth side of the track.
I thoroughly enjoyed the walk, completing it in 9 days.
I observed that in a number of places the track signage, is less clear when travelling Sth to Nth, than in the opposite direction.

Regards,
Graeme Beveridge
5 Enderley Av.
Surfers Paradise, 4217

Tel. (07) 5538 5578