Fruit Tree Pest Update for 2013 Robert Ll. Morris, Emeritus University of Nevada Email: morrisr@unce.unr.edu Questions: Extremehort@aol.com Blog: Xtremehorticulture of the Desert
The UNCE Orchard
100 yards east of N. Decatur and Horse Drive, North Las Vegas
1997: 2005: 2006: 2007: 2008: 2009: 2010:
Over 600 fruit and nut trees, grapes, berries. Nopales, blackberries, raspberries, strawberries, tomatoes Wine grapes Melons, asparagus Tomatoes, sweet onions, garlic, melons Herbs, hoophouse Hops
Fruit trees include: almond, apple, apricot, cherry, figs, jujube, nectarine, peach, pear, Asian pear, persimmon, pistachio, plum, pomegranate, quince and interspecific hybrids such as pluots, apriums, plumcots.
Success of Fruit Trees in the Desert Success is due to: Desert climate Quality plant material Use of compost Whitewash Wood mulches Sanitation Protection from vermin Timely applications of fertilizers Appropriate irrigations Pest control when needed
Whitewash Reduces Borer Damage
Whitewash at time of planting Most important: south and west-facing trunk and limbs; upper surfaces of limbs White or off-white latex paint diluted 50/50 (equal parts) water and paint Reduces sunburn Reduces borer infestations due to sunburn Renew every three to four years
Compost at Planting Enhances Growth
2007 compost incorporated
2006 compost on surface
Staking = Faster Establishment
Staking is done to immobilize the roots, not the top. Stake low enough to allow the top to move but not the roots. Stakes should be pounded deeply into solid soil at the bottom of the hole. Staking should NEVER be needed to support plant canopy if plants are good quality.
Wood Mulch Improves Tree Growth and Health
Wood mulch should be a variety of different chipped woods. Mulch should be wood, not bark alone. Mulch should be 4 to 6 inches deep. Mulch should be kept 12 inches from tree trunks the first five years. Using wood chipped from local trees does not increase insect or disease problems.
Wood Mulch Improves Tree Growth in the First Season Wood surface mulch
Wood surface mulch No surface mulch
Rabbit Prone Areas Need Rabbit Fencing Rabbit prone areas are near golf courses and open desert. Both desert cottontail and jackrabbit will damage landscapes. Trees trunks are prone to damage until five years old. Tree limbs closer than 3 feet to the ground will be damaged by jackrabbits. 1 inch hexagonal chicken wire is adequate if the bottom edge is buried.
Water, Not Your Foot, is the Best Way to Remove Air Pockets
Your foot damages roots if you stomp on the planting hole. If soil is prepared well, water will remove air pockets and improve establishment speed. Make sure to plant in a wet hole. Basins around the plants force water deep into the root zone.
Regular Irrigations During Fruiting Improve Fruit Quality ď Ź ď Ź
Fruit growth follows double sigmoid curve. Water is critical during these two growth phases for good fruit growth and size.
Fruit Growth
Summer Pruning Health and Fruit Production • • •
• • • •
Increases light inside the tree canopy Reduces interior limb dieback Distributes fruit production all through the canopy Improves fruit quality Helps keep the tree dwarfed March - April only Remove only new growth
Fertilizers Control Growth and Affect Health
Baseline and periodic soil tests should be done Nitrogen most important for new growth and most limiting Lawn fertilizer ratios are usually adequate (3-1-2) Single application is done in late winter Split application done in late winter and after harvest Iron is needed for most fruit trees in the rose family Best is iron in EDDHA chelated form applied in January
Insects and Pests That Can Move General Pests Borers Birds Ground Squirrels Rabbits Apples and Pears (Pome fruits) Coddling moth Peaches and Apricots Peach twig borer Nectarines Thrips Pomegranate, Almond and Pistachio Leaffooted plant bug
Sanitation Reduces Pest Problems
Ripe fruit attracts critters that attack fresh fruit on the tree Fruit should be picked up as soon as possible when it falls It should be buried in compost or sealed in containers
Borers Attack Nearly Any Tree
Borers damage landscape and fruit trees Peaches and nectarines worst borer problems in fruit trees Borers can be present without noticeable damage Merit labeled for borer control may not give you good PR Prevention and sanitation will help reduce borer problems
Borer Removal ď Ź
ď Ź
Loose bark is removed with a knife during winter Branches more than 50% dead are removed
Birds Feed on Ripe Fruit ď Ź ď Ź
Birds normally damage soft fruit ready to be harvested Harvest fruit as soon as damage first appears or early when still firm
Ground Squirrels
Ground squirrels will steal or feed on almonds, pistachios, grapes, soft fruit, damaged pomegranates, vegetables and many others Can be a serious problem Baits
Codling Moth Damages Apples and Pears
Sanitation, pick up fallen fruit Pheremone traps Sprays of Bt or Spinosad
Wormy Peaches
Wormy peaches, nectarines, apricots, almonds Pheremone traps (different pheremone) Sprays of Bt or Spinosad
Fruit Scarring on Nectarine ď Ź ď Ź
Nectarine fruit skin is horribly scarred and fruit deformed Repeat weekly sprays of spinosad, soap, Neem as fruit develops
Leaffooted Plant Bug Insect From Hell
Any fruit but usually noticed on pomegranate Causes nut drop in pistachio, blanks in almond, early fruit drop or deformed fruit in pomegranate Usually seen in June when numbers have multiplied Winged and can fly but not well Overwinter in the landscape Dormant oils, Sevin and synthetic pyrethroids
Diseases No disease agent (Abiotic) Sunburn Iron chlorosis Bitter pit, corky spot Disease agent (fungus or bacterium) Fireblight (bacterium) Shothole (Coryneum blight, fungus)
Sunburn – Fruit Likes Partial Shade Sunburn – apples, persimmons, others
Brown Spots in Apple Pear Flesh
Apple it is called “Bitter Pit” Pear it is called “Corky Spot” Calcium deficiency in developing fruit Looks bad but is safe to eat 5 sprays of calcium chloride (food grade) to the fruit a week apart as it is in early development Use wetting agent and spray fruit to runoff
Fireblight Fireblight – apples, pears, Asian pears
Shothole or Coryneum Blight Shothole fungus – peaches, nectarines
Resources Xtremehorticulture of the Desert http://xtremehorticulture.blogspot.com/ Send questions and pictures to Extremehort@aol.com NEW!! Desert Horticulture yahoo discussion group Dave Wilson Nursery http://www.davewilson.com/ Fruit Pests University of California IPM Online http://www.ipm.ucdavis.edu/