CU-Structural Soil™ is a revolutionary patented and trademarked tree planting medium developed at the Cornell University Urban Horticulture Institute. It is used when planting a tree in a sidewalk or other area that restricts the growth of the roots; it allows the tree to grow happily and keeps sidewalks and parking lots from being destroyed. The medium includes stones, soil and other materials meeting certain specifications such that it allows the tree roots to benefit from good drainage, aeration and nutrition.

Title: Using CU- Structural Soil™ in the Urban Environment
Author/Source: Urban Horticulture Institute, Cornell University
Description: Crystal-clear explanation of the benefits of using this product, with great photos and images so you can understand what CU Structural Soil™ is, and how and what to use it. On page 12 you will find a list of some street tree species appropriate for planting in this product.

Title: Tree Planting Standards
Sponsoring Organization: New York City Parks and Recreation
Description: While based on New York City, this extensive brochure may be helpful to municipalities. It explains exactly HOW and WHEN to use CU Structural Soil™ for urban sites. There is also a discussion of tree pit size, extolling the benefits of planting several trees in a larger pit, rather than several trees in several separate small pits.