What type of expert do I need for grass, tree, and garden advice?

[Anonymous]

Last summer we filled in a rocky, hilly unused small backyard, planted grass, and tried to make it into a useable play area for our small dogs. The new earth/soil seems to be receding and starting to slope back downwards, the grass is almost dead, and half the shrubs have died. What kind of an expert do I need to hire to tell me how to fix this? It involves soil and grass but also trees since there are a few in the background and plants/shrubs. We don't necessarily need them to do the work--just tell us what went wrong and how to fix it.

TIA

[Anonymous]

You could start with your local Extension Service -- DC or what county are you in?

[Anonymous]

Horticulturist

[Anonymous]

OP. Fairfax County