Oak Spider Mite – Oligonychus bicolor

Oak Spider Mite (Oligonychus bicolour)

Common Name: Oak Spider Mite

Latin Name: Oligonychus bicolor

Appearance:

• This is a little (0.5 mm long) dark reddish brown mite that prefers oaks (Quercus spp.) but may also be found on birch, beech, elm, and hickory.
• The mites are typically found around the midrib of huge oak trees’ lower leaves.
• Oak spider mites have style-like mouthparts to extract plant juices from leaves, resulting in scattered chlorotic stippling. Before fading, the leaves become yellow or golden in appearance.

Host plant:

Chestnut(Castanea spp.), Elm (Ulmus spp.), Beech (Fagus spp.), Birch (Betula spp.), Hickory (Carya spp.) and Oak (Quercus spp.

Damages caused by Oak Spider Mite:

Spider mites have small mouthparts adapted to pierce individual plant cells and remove their contents. As a consequence, little yellow or white speckles appear. The foliage becomes yellow or bronzed when many feeding places are close together. When a plant’s foliage becomes bronze, it generally drops prematurely. Plants that have been heavily affected may become discoloured, stunted, or even dead. Spider mites that spin webs may cover the leaves with fine silk, which accumulates dust and seems unclean.

Life history and habits:

All spider mites go through the same developmental phases. Adult females often deposit their eggs on the host plants. The eggs hatch into the first stage, known as a larva, in days to weeks. Larvae have spherical bodies and just three pairs of legs. The larvae eat for a few days before seeking a secluded resting place and moulting into the first nymphal stage. The first nymph is now equipped with four pairs of legs. The initial nymphs eat for a few days before moulting into the second nymph. Second, nymphs eat, rest, and moult into adulthood. Males are often the size of a second nymph, with pointed abdomens. Female mites have rounded abdomens and are the biggest mites seen. Most spider mites spend the winter as eggs, but the two-spotted spider mites overwinter as adult females resting in safe areas.