Pinyon Pitch Nodulemaker – Retinia arionensis

Pinyon Pitch Nodule Moth (Retinia arizonensis)

Latin Name: Retinia (Petrova) arizonensis (Heinrich)

Common Name: Pinyon Pitch Nodule Moth

Appearance:

• Pitch nodule moths are seldom seen, but their devastation is noticeable.
• Moths have a 3/4-inch (19 mm) wingspan and are rusty brown with speckled forewings. During an attack, branch tips fade, and pitch nodules develop at the insects’ feeding spots.
• Pitch nodules are hollow pitch balls 1/2-1 inch (10-25 mm) in diameter, spherical, smooth, and generally pale purple or red.
• They are most commonly found near the crotch of two or more twigs on pinyon pines. The needles on the fading twigs finally break off, and the twigs fall off.

Host plants:

Pinyon pine and ponderosa pine

Territory:

Throughout the United States

Damages caused by Pinyon Pitch Nodule Moth:

Leaders are periodically damaged, which can result in trees with many terminals. Insect populations and damage might be plentiful in some places. Attacks affecting the terminal growth of ponderosa pine happen.

Life history and Habits:

Pitch nodule moths reproduce once a year. In July or early August, the tiny reddish-brown moths emerge through holes in the pitch nodule. Eggs are deposited on the current year’s growth needle sheaths. Newly born larvae eat young needles before digging into the bark of twigs and branches at nodes or whorls. Pitch nodules grow at feeding places, where larvae eat and are sheltered in winter. Larvae are about 1/2 inch (13 mm) long, reddish-yellow in color, with a black head and a dark region behind the head when fully developed. In June, pupation takes place inside the pitch nodule. Before emerging as adults, pupae migrate close beneath the surface of the pitch.