TY - JOUR AU - Dahlgren, Randy A AU - Horwath, William R AU - Tate, Kenneth W AU - Camping, Trina J TI - Blue oak enhance soil quality in California oak woodlands JF - California Agriculture JO - Calif Agr Y1 - 2003/04/01 VL - 57 IS - 2 SP - 42 EP - 47 PB - University of California Agriculture and Nature Resources SN - 0008-0845 UR - http://dx.doi.org/10.3733/ca.v057n02p42 L3 - 10.3733/ca.v057n02p42 AB - Blue oaks create islands of enhanced soil quality and fertility beneath their canopy. The quality of soil beneath the oak canopy is considerably better than that of the grasslands adjacent to the trees. We found evidence of improved soil quality under blue oaks for physical, chemical and biological soil properties. The type of vegetation (oak versus annual grasses) has a much stronger influence on soil organic matter and nutrient pools than does soil parent material. Removal of oak trees results in a rapid deterioration of soil quality with the majority of the loss occurring within 10 to 20 years after tree removal.