Q.i LIVE IN ZONE 6, AND HAVE A VERY MOIST AREA, COMING FROM MY NEIGHBOR, 16 INCHES X 50
WHAT CAN I PLANT IN IT
Depending on the amount of water and the drainage of your soil, you may need to address the flooding and amend the soil.
These articles will help you get started.
https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/what-is-well-drained-garden-soil.htm
https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/yard-drainage-problems.htm
https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/how-to-improve-clay-soil.htm
https://www.gardeningknowhow.com/ornamental/water-plants/wgen/water-tolerant-plants.htm
https://www.gardeningknowhow.com/edible/fruits/fegen/fruit-trees-in-wet-conditions.htm
https://www.gardeningknowhow.com/ornamental/flowers/fgen/moisture-loving-wildflowers.htm