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Cottonwood Borer

Cottonwood Borer – Facts, Identification & Pest Control

The Cottonwood Borer is a longhorn beetle insect that is fond of cottonwood trees. Although cottonwod borers will destroy poplar and willow trees, the trees they mostly destroy are cottonwood trees. These borers are roughly 1 to 1.5 inches in length. They are easily recognized because of black stripes that are veiled by cross stripes and patches of finely-shaped white hairs surrounding the black stripes. Female beetles of this species are the first to embark on destroying the trees.

How Cottonwood Borers Damage Your Cottonwood Trees

Female cottonwood borers head for cottonwood tree bases and commence to dig small holes into the crown of tree barks and roots that buttress trees.Once they finish digging the pits, the borers then deposit their eggs in the pits. The eggs hatch out approximately 16 to 18 days later. Larvae from the eggs bore down into the inner barks of trees to form huge pupal chambers.

A Clever Pupation Process Leads To Repetitive Cottonwood Borer Life Cycle

Cottonwood borers exist in a clever gallery of chambers as they undergo a pupation process for approximately three weeks. New adults then chew exit holes to exit the pupal chambers and travel into soil. When they get into soil, they begin their life cycle of tree digging destruction and egg laying. This process results in the creation of new borers in large tunnels that are built by borer larvae.

Entomologists note that larvae tunnels may extend as much as 8 inches in length with a 3-inch wide diameter, which has an oval-shaped area. Female cottonwood borers create their tunnel size based on how large the host trees are. Adult cottonwood borers reside on the larvae-infested trees, but they position themselves on higher areas of the trees during daytime.

Reproductive Behavior Of Male Borers

Male cottonwood borers use pheromones to locate a female near the roots of a tree. Pheromones is a chemical substance that males externally secrete in order to influence the organism of female borers. After depositing the secretion substance, the male promptly mounts a female borer without conducting any courtship whatsoever. For unknown reasons, male borers clearly do not choose large females to mate with.

Some aggressive male cottonwod borers defend their female partners during the copulation act.
Another single male will sometimes attempt to dislodge a male and female who are engaged in mating. The rival does so in a blatant attempt to remove sperm from the male it considers to be a rival.

What does the defending borer do to maintain its position and dismiss the aggressive male in such a case?
It grabs the outrageous offending rival’s antenna with the very strong mandibles that cottonwood borers are blessed with. This apparently serves to intimidate the impertinent male rival.

Guarding The Female After Copulation

There is an additional form of trickery that male borers use during copulation. They guard their female partners following the mating drama to ensure that their unique sperm is not removed by an aggressive rival before egg fertilization takes place. Male cottonwood borers, it appears, are serious about their male reproductive power.

Young Trees Falter And Adult Borers Damage Tender Shoots

Young cottonwood trees are susceptible to damage when they are tunneled into under the trees’ bark as well as around its base. The damaged trees then falter and fall to the ground when weather conditions produce high winds.

Not to be overlooked is the fact that adult borers contribute to destruction as well when they feed on leaf stems and bark that cover tender shoots. This activity causes shoots to break and subsequently wither and die.

Larvae Disrupts Phloem of Shoots Nourishment Distribution

Experts suggest that the infrastructure of cottonwood trees is also compromised when larvae bore into the phloem of shoots. The phloem is responsible for conducting substances from tree roots to other parts of trees that need nourishment.

Properly Managing Tainted And Infested Trees

Managing damaged trees properly is the best thing to do when an infestation occurs. That entails removing the tainted trees and destroying the infested ones. Some experts recommend that you dispense insecticide into the soil and lower trunk of trees that are damaged by adult borers. Perform that activity in order to control and reduce the insects’ adult population. Your overall aim should ideally be to prevent the adult cottonwod borer from laying more eggs for pest control.

Holding A Cottonwod Borer To Examine It

Exercise care when handling a cottonwood borer. Its mandibles are quite obvious because they are so large. The mandibles are as long as the insect’s entire body and are their fiercest weapon. If you are not handling the insect in a careful manner, you could end up being bitten. In the event you hear a buzzing or hissing noise while handling the insect, that sound is definitely coming from the cottonwood borer.

Choosing Proper Sites To Plant Cottonwood Trees

The cottonwood borer is plentiful in the Great Plains area. If you live in that area, make sure that you choose proper sites for planting your cottonwood trees. Experts recommend that you choose sites that have good irrigation and fertilization. Those features will help to reduce any prospective injuries caused by cottonwood borers. The bug experts also advise that you can easily scoop out small larvae from tree bases with the use of a pocket knife.

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