black black dirt

[plowindeeper]

I have a Holly tree on my place that is about 4 ft around and 70 ft tall granddaddy said it has been on this place I bought next to him and my parents all his life ( he's 87 ) There has always been a garden under this tree as long as he can remember also.For 50 ft around this tree there is black black dirt for about 2ft deep all the rest of the dirt is brownish this spot grows great tomatoes
soil samples show there is not any difference between dirt colors. Black dirt will grow 2X's amount of any thing we plant there. Brownish does great but not near what the black dirt does. Does the holly tree have anything to do with it
Your thoughts please

 

[jinman]

Your soil samples look for specific contents and may not show what it causing the difference. It could be porosity or even that the black soil has a different heat profile. Certainly, black holds heat better than the lighter soils and also absorbs more light.

 

[dusty3030]

Maybe all the mules hung out under it back in the day for shade or a back scratching post

 

[Taylortractornut]

Holly leaves are really waxy and take a while to break down without help from worms. I pick up leaves in town and add them to the garden. i pile the holly leaves up seperate as they take longer. Ive seen red worms eat the leaves and leave castings. THe tree as it sheds leaves and they break down make Humus the black dirt and leave deposits of boron and other trace elements that the leaves contained.

I havent had alot of dealings with holly trees but where my magnolias shed and accumulate the ground is black around them.

 

[DaveMK]

More organic matter in soil around holy tree.