Are There Really Laws About My Backyard Fruit Trees?
March 03 2010
Yes, it's true that many Oregon counties (including Umatilla) have laws that require the control of destructive pests and diseases of fruit trees on your property to prevent their spread to commercial orchards. Before you plant new fruit trees, or if you already have fruit trees, be sure that you're ready and willing to accept the responsibilities that go along with owning them; particularly apple, pear and cherry trees.
ONE LITTLE FRUIT TREE IN MY YARD ISN'T GOING TO HURT ANYTHING, WILL IT?
Think again. Oregon is one of the country's leading producers of apples, cherries and pears. When Oregon Extension agents in Umatilla County mapped the location of coddling moths caught in traps, they found the problem was far greater in backyard trees than in orchards. This isn't surprising since home owners rarely apply the several rounds of pesticides required each year to control apple maggot, codling moth, San Jose scale, scab, and cherry fruit fly. One untended backyard fruit tree can harbor pests that then spread to commercial orchards, and once that happens, our local economies have a lot to lose.
The fruit industry in the Milton-Freewater area alone generates about $85 million a year, employing about one-third of those who live in the 97862 zip code. Just one cherry fruit fly in a shipment of the fruit means foreign markets can reject the entire load. In some Asian countries, if inspectors find three incidents of codling moths in a shipment, they refuse apples from the U.S. a year. The last time that happened in 2004, guess where the apples were from? Milton-Freewater! That translates into a huge loss of income to some of the area's largest employers. Indeed, last year, even California refused to take cherries from Milton-Freewater because of three cherry fruit fly infestations, causing local growers to lose millions of dollars in revenue.
As a result, advice from Umatilla County Extension Agent Clive Kaiser and others is to remove backyard fruit trees rather than planting them if you're unable or unwilling to keep them pest free. Consider replacing them with trees that do not harbor pests. Your Extension Agent can provide you with a list of those trees. The lists of trees to avoid and those to consider are also available on the OSU Extension website http://extension.oregonstate.edu/umatilla/mf/
WHAT CAN HAPPEN IF I DON'T TAKE CARE OF PESTS ON MY FRUIT TREES?
So, what are the potential consequences if you ignore their advice? Many counties now have Horticultural Pest and Disease Boards and Control Agents that have the authority to order you to remove a fruit tree if they find it harbors pests. You may be asked to do so by a representative of the Board, who will return to make sure that you have complied. If you haven't, the Board can hire a commercial pesticide applicator to spray your trees and charge you for the service. If you refuse to pay the bill, they can place a lien against your property until you do.
OK, THAT'S SCARY STUFF, BUT I LOVE FRUIT TREES! HOW CAN I KEEP PESTS UNDER CONTROL?
Still undeterred? You're life will be a lot easier if you steer clear of fruit trees that require multiple pesticide sprays: apples, cherries and pears. Alternatively, consider planting plums, peaches or apricots. Although they also require pest and disease control, they can generally be successfully grown here and do not harbor pests that are serious as those that attack apples, cherries and pears.
Different pests require different treatment programs. In addition to using pesticides, there are cultural and biological practices that can help prevent and/or manage diseases and insects. You'll find lots of information on the website for Oregon State University's Extension Office: http://extension.oregonstate.edu/umatilla/mf/
If you do have apples, pears or cherry trees, following are strategies to control pests on your trees. If you do not have the equipment to do this you will need to hire a reputable pest control spray service. Spraying your trees, and picking fruit, will be made much easier if you keep your fruit trees short enough to avoid the use of a ladder (as most orchardists do to reduce labor costs). Following are guidelines for keeping trees pest free. Keep in mind the rules and regulations for pesticides can change frequently and must be applied according to label instructions. Check with your Extension Agent for the latest.
Apples and Pears
Apples, pears (even crabapples and flowering pears), walnuts and hawthorns are host plants and attract codling moth "worms" or larvae. One female moth lays dozens of eggs on a tree that hatch into "worms" or larvae which typically feed on the leaves until they are up to ½ in length. After this the larvae must look for an apple to bore into, to feed on the seeds and complete their life cycle. Once inside the apple, pesticides can't reach the worms. Once they have consumed sufficient protein in the form of apples seeds the worms either become adult moths during the height of summer or in fall, they drop to the ground, burrow in, and sleep for anything up to two years before re-emerging as moths.
Top three control strategies:
- Pesticide sprays starting 10 days after petal fall, and continuing every 10-14 days until harvest (at least 3-5 sprays per season are necessary).
- Periodically scouting, picking and destroying all infested fruit on the tree.
- Early in the season, bag all fruit on the tree.
- Remove all fruit from the trees.
Apples and hawthorns also attract apple maggots. The adult fly is ¼ inch long. One female can lay dozens of eggs under the surface of apple fruits. Eggs hatch into hungry maggots that tunnel and feed within the fruit. Once inside the apple, pesticides can't reach the maggots.
Top 3 control strategies include:
- Pesticide sprays starting early July and continuing every 10-14 days until harvest (3-4 sprays/year).
- Periodically scouting, picking and destroying of all infested fruit on the tree
- Trapping adult flies with sticky traps or red spheres.
Cherries:
Cherries attract western cherry fruit fly. The fly is less than ¼ inch long. One female fly lays dozens of eggs individually under the surface of a cherry fruit. Each egg will hatch into a maggot that tunnels and feeds in the fruit flesh. Once inside the cherry, pesticides cannot reach the maggots (about ¼" long).
Top 3 control strategies include:
- Pesticide sprays targeting adult flies starting late May and continuing every 7 days until harvest (5-6 sprays per year).
- Trapping adult flies with sticky traps.
- Removing all fruit from the trees.