Honeylocust Spider Mite (Platytetranychus multidigituli)
GDD Window (base 50): 220-250 (egg hatch)
Overview:
- Orangish and yellow-green, overwintering adults are1/50” and found in bud scars and bark cracks
- Classified as a warm season mite
- Eggs from overwintering adults are laid in the early spring & hatch shortly after bud break and begin to feed on foliage
- Multiple generations per year
- All stages are present by the beginning of summer
- Greatest damage occurs during late spring and again during late summer
- Heavy infestations may cause foliage to brown and die
- Causes stippling on foliage
- Refoliation can occur if damage occurs early in the season
- Host plants: Honey locust
Management:
Cultural Practices:
- Natural predators: lady beetles, lacewings, predatory thrips, predatory mites
- Scout using a 10x to 15x hand lens during early spring
- Examine trees with a history of this pest
- Mites thrive in hot, dry conditions, so ensure plants have enough water and shade
- Reduce plant stress
- Do not spray carbaryl (aphrodisiac)
Materials:
- Contact insecticides:
- Avermectins [6]: abamectin
- Mitochondrial c. IIII electron transport inhibitors [20B]: acequinocyl
- Pyrethroids [3]: –thrins, fluvalinate
- Systemic insecticides:
- Tetronic acids [23]:
- Spiromesifen (reduced risk)
- Considerations:
- Will harm non-target species
Biorationals:
- Horticultural oil (3%) can be used if leaf buds have not yet opened
- Later in the spring, use a summer oil (1-2%) or soap
- Thiazolidnones (MGR) [10A]:
- Hexythiazox
- Effective against eggs and immature nymphs
- Causes new eggs laid to be sterile
Management:
Landscape Pest Notes: Some Early Spring Insects/Mites – PPA
- This mite species can have multiple generations during the year & peak infestations often take place in late spring & and again in late summer. (Photo Credit: Steven K. Rettke, Rutgers Coop. Ext.)
- Honeylocust Spider Mites will primarily feed on leaf undersides & concentrate at the base of the leaflets. (Photo Credit: Steven K. Rettke, Rutgers Coop. Ext.)
Disclaimer – Materials do not cover all possible control scenarios and are intended for licensed professionals. Tradenames do not imply endorsement and are used as examples. You must strictly follow the label for each compound prior to use. Rutgers is not responsible form is used materials or damages thereof. The label is the law. Labels will provide detailed information on use and restrictions. Additionally, application intervals, compatibility, surfactant use, PHI, PPE, important and other key information is described in detail. Always discuss treatments with your local agents. Note: Neonicotinoids can only be legally applied in commercial agriculture settings by licensed applicators. Guidelines and recommendations made in this presentation are specific to the state of New Jersey.