Q.Soil under/after chicken
I have questions about soil after chicken. The chicken coop was over the soil for nearly a year and I thought that I can use it for gardening but later I read that the soil is useless as nothing will grow. Can I build a raised bed over the soil or build a compost pile over it?
Was this an chicken pen area?
Chicken Manure makes excellent compost. Here is a link with more information.
I would not see any reason why you could not garden over an area as long as the manure has aged.
I would recommend a soil test prior to planting.
https://www.gardeningknowhow.com/composting/manures/chicken-manure-fertilizer.htm
https://www.gardeningknowhow.com/composting/manures/the-benefits-of-manure-in-your-garden.htm