How to Treat Date Trees to Prevent Worms

Two types of moth larvae sometimes attack ripening dates.

Dates are a drupe fruit that several members of the Palm tree genus Phoenix produce. The Senegal date palm, Canary Island date palm and traditional African date palm, or Phoenix dactylifera, all give us the sweet, tasty fruit we call dates. They are attractive trees that can reach heights of 100 feet or taller, although they grow only in USDA climate zone 9 and higher. Larvae of the raisin moth (Cadra figulilella) and the greater date moth (Arenipses sabella) sometimes attack ripening fruit, both on and off the tree. Pheromone traps can help to control the adult population.

Things You'll Need

• Pest monitoring kit
• Pheromone lures
• Pesticide (optional)

Instructions

1. Hang special monitoring traps near ripening dates to attract and gather adult members of the moths that produce the worms, or larvae, that eat dates. Knowing the specific species you are dealing with is important in planning your treatment strategy.

2. Hang one monitoring trap in each orchard or field of date palms. Hang more traps if you are evaluating an area larger than 10 acres or if you believe your population of raisin moths or greater date moths is especially large.

3. Hang one pheromone lure near each tree after you determine the type of moth that is present in your area. Such lures can effectively reduce the population and will confuse the insects, limiting their ability to find a mate.

4. Spray with approved pesticides if the infestation is severe. Field trials in Egypt in 2007 and 2008 concluded that the products Proclaim and Deltachem reduced the occurrence of the greater date moth by 75.74 percent in 2007 and 85.48 percent in 2008, according to an article presented at the International Date Palm Conference.

Tips & Warnings

• When you order a monitoring kit for the moths that affect date palms, it will include all of the various pieces you need, such as wire hangers, insect removal sticks, plastic tops and instructions.

• The naturally occurring soil bacterium, Bacillus thuringiensis (Bt), is ineffective against the worms that eat dates because they hatch inside the fruit and you apply Bt to the outside of plants to control other types of worms, such as the tomato hornworm.

References

• Purdue University Extension; Date; Julia Morton; 1987
• Cambridge University: Bulletin of Entomological Research, 58
• Arbico Organics: Raisin Moth, Cadra figulilella Pheromone Lure
• International Date Palm Conference: Control of the Greater Date Moth