Sharraxaadda

This is a general question and an example: It's my understanding that sidewalks may be built on private property, but they are on a municipal easement. When vegetation intrudes upon the sidewalk, whose responsibility is it to rectify the situation? The example photo demonstrates poison ivy extending onto the sidewalk at 1329 Ragley Hall Road, but there are other instances of bushes, etc. that have overgrown the sidewalk corridor.