Weed control is perhaps the most important task during this establishment phase, particularly to reduce grass competition prior to canopy closure. Where moisture is not limiting, cover crops could be planted and mown between the rows while maintaining an herbicide cleared strip beneath the trees. Fertilization and irrigation during dry periods will promote faster growth. In Oregon, black walnut encounters no significant disease, insect or deer browse problems. Early training and pruning are necessary for the production of high-value veneer and sawlogs.
Training starts in the second year to eliminate branch crotches and other form defects.
Modified farm equipment such as a tractor-mounted cherry picker can be used for pruning. To minimize knot size, limbs should be removed before they reach an inch in diameter. Thinning at about age five is also recommended for black walnuts. The best formed, apically dominant trees are selected to grow on after removal of the poorer trees. The Oregon Chapter of the Walnut Council presents special workshops on pruning black walnut.