willow tree roots

[sharon214]

I moved to Virginia from Arizona recently and have a question about a weeping willow tree on the empty lot (which I also own) next to my house. I am having a patio put in and must excavate a hill in back. I would like to put the dirt from the excavation in a depression surrounding the willow tree. Some very large tree roots are exposed and my neighbor said that if I cover them the tree will die. Is this correct? I don't want to kill the tree and it would only be about 6" of dirt on top of the roots. Thanks for any help.

[grandpasrose]

It is not normally advised to add soil on top of exposed tree roots as this then cuts off the roots access to oxygen. What you could do however, is bring the dirt up to where the roots start showing at the furthest point from your tree, and then place an organic mulch such as chopped straw, shredded leaves, cocoa beans, or untreated bark mulch around the remainder of the area around the tree. This allows oxygen to still get to the roots of your tree, but fills in that unwanted dip. I would not put the mulch any thicker than 4 inches or so.
Hope this helps!
VAL

[The Helpful Gardener]

For most trees I would NOT recommend this practice, but in this case, it being a willow and all, I do not think this would present a big challenge for the tree. Willows are notorious rooters and I suspect that the new roots to keep the tree oxygenated wouldn't be more than a few days developing.

That said, discretion is the better part of valor, and Val's plan will accomplish your goal, albeit at a much slower pace. A tree's pace. And as Rosemary Verey said "Gardening is easy. You just need to learn to think like a plant." Start with 3" of dirt and the mulch. See how things go...

Scott