This might have had something to do with my email and followup from the Dutchess BPAC leader, all with absolutely no feedback:
To judge from the shattered stems lining the route, NYSDOT positioned an articulated rotary mower vertically and ran it along the guide rail, cutting the Japanese knotweed more-or-less flush with the rail, then cleaning up most of the debris. Absent glyphosate treatment, the bushes will return in full force next summer.
Even though the disintegrating pavement isn’t any more rideable than before, not having weeds brush our elbows and grab for our eyes makes for a much more comfortable riding experience; now, we’re set for the peak Halloween-to-Groundhog-Day riding season.
As NYSDOT says: “Maintaining roads goes far beyond the edge of the pavement.“