Rose eating caterpillars
Last year the roses were covered with ants and this year it’s these funny looking caterpillars which I discovered are Rose Sawfly Larvae (Arge pagana). Yuck. According the Royal Horticultural Society:
Large rose sawflies are insects with pale spotted black, green and yellow caterpillar-like larvae that eat the leaves of roses, sometimes causing severe defoliation.
As I had no sprays to hand they advised removing these ‘larvae’ by hand (no way) so I hosed down vigorously and then sprayed the tree with neem oil. The ants found a new home this year or maybe they were bullied out by these creatures. Have to keep an eye on this.