Mycorrhizal plants are often more drought tolerant and can resist many root diseases that might otherwise threaten them. Soil networked with mycorrhizal fungi has proved to be important in resisting weed invasion. The network builds soil structure, which helps hold the soil together and allows many seedlings to survive that might not otherwise, increasing plant diversity. A network of mycorrhizal fungi in the soil can be crucial in restoration, reclamation, and erosion control. Soils must often be inoculated with the appropriate mycorrhiza in order to accommodate the species and diversity of plants being planted.