Prune: When completely dormant, every December or January.
Spray: Dormant spray in December or January with Master Nursery Pest-Fighter Year-round Spray Oil and Microcop. Follow label directions for appropriate quantities.
Always check with your Nursery Professional to properly diagnose problems before undertaking additional sprays.
Shot Hole Fungus:
- Spray: Spray trees again with Microcop at pink bud and full bloom stage.
- Pruning: Prune to allow good ventilation.
- Sanitation: Remove and destroy affected buds and blossoms during bloom. Remove and destroy maturing fruit when symptoms appear. In August or September, remove mummies and fallen fruit. Do not compost.
- Irrigation Methods: Use basin or drip irrigation to avoid wetting blossoms, foliage and fruit.
Brown Rot Blossom Blight:
- Spray: Spray trees again with Microcop at pink bud and full bloom stage.
- Irrigation Methods: Use basin or drip irrigation to avoid wetting blossoms, foliage and fruit.
- Sanitation: Remove and destroy affected buds and blossoms during bloom. Remove and destroy maturing fruit when symptoms appear. In August or September, remove mummies and fallen fruit. Do not compost.
- Pruning: Prune to allow good ventilation. Remove affected twigs, fruiting wood and branches. Do not compost.
- Harvest nuts when 95% to 100% of nuts at eye-level have split hulls.
Fertilize: Use Master Nursery Fruit Tree & Vine Food twice a year, around Memorial Day and Labor Day. If you prefer organic fertilizers, use Dr. Earth Fruit Tree Fertilizer two to three weeks earlier. Water in immediately after application.
Water: At planting, construct a soil basin at the drip line of the tree. As the tree matures, extend the basin to the span of the drip line. Flood weekly during the first year and then at 2 to 4 week intervals when the tree is mature. If a drip system is used, place hosing along the tree’s drip line with emitters on 18 inch centers. This system will also need to be adjusted as the drip line expands. Both of these methods are preferable to sprinklers, since they reduce water splash, a common byway of fungal spores. If sprinklers must be used, adjust heads so that they angle water low and away from the trunk.
Other Comments: If unusual symptoms appear, bring several leaf and twig samples to Wegman’s Nursery for evaluation.
Watch for oozing of amber-colored gum on twigs, branches or trunk, which may indicate the presence of borers or fungus. Bring several leaf and twig sample to Wegman’s Nursery for evaluation whenever these or other symptoms appear.
Paint trunks and lower branches of young or non-vigorous trees with a one to one mixture of white interior latex paint and water to prevent sunburn injury and reduce borer infestations. Apply the paint mixture from 2 inches below the soil surface to 3 feet above.
Adapted from Ogawa and English (1991), Diseases of Temperate Zone Tree Fruit & Nut Crops, UC Extension Publication 3345; and from Flint (1998), Pests of the Garden and Small Farm, 2nd Edition, UC Extension Publication 3332.
