Pest Control: Spider Mites

There are many species of spider mites (around 1,200 species) all belonging to the family Tetranychidae. They generally prefer living in the undersides of leaves, where they spin protective silk webs which are also used to protect their colonies as well as to travel from plant to plant.

Spider mites can be difficult to spot but if unchecked, later move to the upper leaves. Spider mites vary in color, thus scouting and identification are key.

           

Damage

Retarded plant growth

Spider mite feed on the plant cells, this initial damage will appear as small yellow or brown spots on the leaves. The destruction of the cells results in reduced photosynthesis, plant growth reduction or even, if the infestation is large enough, the death of young plants.

 

Natural Enemies

There are specific natural enemies for different species of spider mites.

The primary beneficial insects that are natural enemies of spider mites are as follows: 

(Click the name of the beneficial insect for additional information) 

BioAndersoni - (Amblyseius andersoni) is a predatory mite that feeds on small arthropod prey and pollen. BioAndersoni is less than 1mm in length and is often used in tomatoes due to its ability to maneuver between trichomes. They are highly effective in targeting two spot spider mites.


BioCalifornicus
 - (Neoseiulus californicus) is an effective predatory mite of a wide array of pest mites. They target two spot spider mites.

BioPersimilis - (Phytoseiulus persimilis) is a predatory mite, proven outstanding, aggressive, and highly effective against two spot spider mites. The adult female is a distinctive reddish-orange color with a pear-shaped body. Its long front legs allow it to move quickly and easily navigate spider mite webs. In suitable conditions, BioPersimilis can develop faster as its prey, allowing it to suppress mite infestation quickly and thoroughly.

In addition to these insects, the following insects also target spider mites along with their primary enemies:

BioCucumeris - (Neoseiulus cucumeris) is a predatory mite widely used in the control of immature thrips (egg and larvae) as well as other species of mites such as broad mites. Although very small (1mm), BioCucumeris can be recognized by its oblong shape and quick mobility along the underside of leaves and in flowers.

BioSwirski - (Amblyseius swirskii) is an efficient predatory mite used for the control of young stages of the western flower thrips as well as the eggs and young nymphs of whiteflies. It also feeds on red spider mites as well as on broad mites.

BioLacewing(Chrysoperla rufilabris) also known as the red-lipped green lacewing, is an insect of the Chrysopidae family. The delicate looking adult feeds on nectar and pollen while the larvae of BioLacewing is the active predator. The three larval instars are the voracious ones.

BioOrius - (Orius laevigatus) is a predatory minute pirate bug equipped with piercing-sucking mouth parts, and two pairs of wings, the front pair being partially rigid. The adult is brown black with grey spots.