Thank you for using Improve Detroit. Utilizing the category "Post to Neighbors" functions more like an online blog. In order to route a request directly to a department, you must select one of the specific categories that are available (for example, "Illegal Dumping" or "Abandoned Vehicle"). Tall grass/weeds may be reported via telephone to the City of Detroit’s Environmental Enforcement Department at 313-876-0974. More information can be found here: http://www.detroitmi.gov/How-Do-I/Request-a-Service/Environmental-Enforcement-Information Thank you.