After conducting research, it appears that there is no boat ramp named Green Lane in Kent County, Maryland. There are, however, several other boat ramps in the county that service different bodies of water and allow different types of watercraft.

One example is the Worton Creek Marina boat ramp, located at latitude: 39.304324 and longitude: -76.090654. This boat ramp services Worton Creek, which leads out to the Chesapeake Bay. It is a concrete ramp that is 20 feet wide and has a maximum depth of 5 feet at low tide.

The types of watercraft permitted on Worton Creek include power boats, sailboats, kayaks, and canoes. However, there are size restrictions for power boats - they cannot exceed 26 feet in length or have a draft deeper than 4 feet.

It's important to note that information about boat ramps, including their names and specific details, can change over time. It's always a good idea to verify the accuracy of any information before relying on it.