According to lasdontrailofhonor.com:

The last bust on the trail is dedicated to the hundreds of women who have dutifully attended our nation’s wounded soldiers for over 200 years. Without the aid and services of these brave women, many more lives would have been lost to infection, disease, and unattended injuries. The bust stands as a testament to their continued service and dedication to our troops at large.

There’s also a monument (not shown here) to eight nurses killed in Vietnam:

As you follow the path leading to the Vietnam Veterans memorial, this humble monument will present itself. This piece of black granite commemorates the sacrifice of the eight nurses who were killed during their service in Vietnam. The monument is placed next to the Vietnam Veteran’s Memorial, showing the significance of their sacrifice during the war to the servicemen they treated. Even though none were from Westchester County, the significance of their story has earned them a place on this beautiful trail.