Yes, grass clippings must be removed according to the HUD guidelines.
Mortgagee Letter 2010-18 states:
“Grass cuts (initial and subsequent cuts) include mowing, weeding, edge trimming, sweeping of all paved areas, and removal of all lawn clippings, related cuttings, and incidental debris (newspapers, flyers, bottles, etc.) removal. The disposal of all clippings and incidental debris should comply with jurisdictional requirements.”
You can see the Yard Maintenance and Snow Removal guidelines on this page of Property Preservation Training
