A Nutty Place to be Born

As the fall season progresses Oak trees can come under attack by pests and disease. This is most commonly manifested by a sticky sap that is dropped from trees covering cars, driveways and patios. This is evidence of something much more invasive and dangerous to the survival of the Oak tree’s future. So, what could be strong enough to destroy the offspring of one of the strongest trees in the United States? A small beetle with a long skinny snout can be one of the culprits. The Filbert Weevil is only about ¼” in length, with a snout almost as long as their entire body. The most common population is in the Western United States and Mexico, although we do have other nut weevils in Tennessee. The Filbert Weevil may be small, but this small pest is responsible for damage to acorns and making it possible for other smaller pests, animals and disease to destroy any possibility of a new Oak tree from sprouting.

The Filbert Weevil takes advantage of a perfect hard shell compartment to continue its life cycle and a place for their eggs to hatch and larva to develop into a fully grown adult.

They begin while the acorn is still on the tree and are smart enough to choose the shady side of the tree. This allows the nut to avoid the sunshine and possible cracking open due to the light and heat. If the nut was to crack open, it would expose their eggs and cause them to die. The method of entry into the outer shell is their snout which they use as a tiny drill. As the female aggressively drills into the hard acorn with her snout, she also gets a meal. The deeper she drills, the more nut meat she can eat on the way to making a home for her offspring. Once the tunnel or canal is drilled out, the Filbert Weevil will lay one or two eggs in the safe hard shell for them to develop. This will not be the only nut used, as the females are capable of laying 25 – 30 eggs in a mating cycle. The larva eventually hatch, safe and sound and surrounded by nut meat to feed on as they grow and mature. As the larva continues to grow, the fall season comes to the point of the Oak tree dropping its potential new saplings. As the acorns hit the ground, the Filbert Weevil gets the signal to emerge from its home as a full grown adult. It is now winter, so to survive the cold weather; the newly born Filbert Weevil bores a hole in the ground so it can survive until the next spring.

With the acorn now hollowed out and the outer shell compromised, it is now a prime target for other pests, animals and disease to enter. Prior to the Filbert Weevil boring the hole and eating out the inner nut meat, many of these other predators would not be able to break the shell or penetrate the interior. So, the potential sapling does not get a chance to produce another Oak tree. Now on the ground, they fall prey to many other insects, birds, squirrels and eventually disease.

This cycle of life begins with the Filbert Weevil looking for a safe, hard shelled and nutrient rich place to hatch their offspring. But in nature’s world of survival this ends the possibility of a new Oak tree.

 

 

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