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Dialeurodes chittendeni

The citrus whitefly shown here, Dialeurodes citri, is in the same genus as the rhododendron whitefly. Photo: Lyle Buss, University of Florida, Bugwood.
Scientific Name: 
Dialeurodes chittendeni
Common Name: 
Rhododendron Whitefly
Growing Degree Days (GDD's): 
None available at this time.
Host Plant(s) Common Name (Scientific Name): 
Rhododendron (Rhododendron spp.)
Insect Description: 

The rhododendron whitefly can be a significant pest of its namesake host in the US. It was first reported in the United States in 1932 on rhododendrons from England; however, the insect may be native to parts of Asia. Reports from British Columbia indicate that rhododendrons brought from Kent, England in 1933 and 1934 were slightly infested with this insect. Adult females lay their elongate-oval, smooth eggs on the undersides of host plant leaves, attached with a short stalk. Nymphs hatch from these eggs and adhere themselves to the leaf underside, where they feed the entire time until adulthood. The immatures may look like and be confused for scale crawlers on the leaf undersides; they are semi-transparent, elliptical in shape, and become rounder as they mature. A single generation of the rhododendron whitefly may occur per year. The overwintering life stage is the immature nymph. Nymphal instars may overlap in their timing at a single location during the growing season, leading to variation. The final nymphal stage (immature) is sometimes referred to as a "pupae"; however these insects do not undergo complete metamorphosis. This final nymphal stage ("pupa") is transparent, white, and papery and 1.25 mm long. Stout spines are found along the edges of the "pupa" and tiny legs and mouthparts may be examined with magnification. Adults are present from mid-May to early August and are dusty-colored (white wings that are 8 mm across and a yellow body). Adults are said to be extremely active during sunny weather (Olds, 1935). When disturbed, the adults may fly around the infested shrub and then quickly settle back on the undersides of the leaves. Adults may be capable of short-range independent movement, however longer distance dispersal is likely human-aided.

Damage to Host: 

The first sign of the presence of the rhododendron whitefly may be mottling of the undersides of older leaves. Undersides of leaves of rhododendron, especially the more tender, terminal leaves are preferred feeding locations for this insect. Heavy feeding causes leaf yellowing and curling. Much honeydew, or liquid, sugary waste, can be produced by this insect. On top of the honeydew, black sooty mold is able to grow. It is believed that rhododendron may be the only host plant of this insect, however susceptibility between rhododendron varieties to this insect is variable. Smooth-leaved species of rhododendrons and their hybrids are preferred. 


Look for overwintered nymphs on the undersides of susceptible host plant leaves. Adults may be present from approximately mid-May to early-August. Shaking shrubs will cause the adults to fly around the shrub, and in a few moments settle back on the undersides of leaves. Yellow sticky cards can be placed close to host plants and monitored for the adults.

Cultural Management: 

Rhododendron varieties with thick and leathery and hairy leaves are often less frequently attacked by this insect. Heavily infested leaves can be hand-picked and destroyed. 

Natural Enemies & Biological Control: 

The study of population dynamics of whiteflies in natural settings is needed. For introduced species, not necessarily the rhododendron whitefly, it is common that the whitefly population explodes rapidly, leading to severe leaf damage and possibly plant death. Natural enemy introductions are also recorded for some non-native whitefly species. These include but are not limited to parasitic wasps and lady beetle predators. In a few cases, whitefly-killing fungi have also been introduced. In most cases, introduction of these natural enemies has resulted in significant declines in the whitefly population. Temperature, wind, rain, and relative humidity can also impact whitefly populations, as well as competition within their own species for nymphal food and adult egg-laying locations (Byrne and Bellows, 1991).

Chemical Management: 

Abamectin (NL)

Acephate (NL)

Acetamprid (L)

Azadirachtin (larvae) (NL)

Beauveria bassiana (NL)

Bifenthrin (NL)

Bifenthrin+imidacloprid (L)

Buprofezin (NL)

Carbaryl (L)

Chlorpyrifos (N)

Clothianidin (NL)

Cyantraniliprole (NL)

Cyfluthrin (NL)

Diflubenzuron (N)

Dinotefuran (NL)

Fenazaquin (NL)

Flonicamid+cyclaniliprole (N)

Tau-fluvalinate (NL)

Gamma-cyhalothrin (L)

Horticultural oil (L)

Imidacloprid (L)

Insecticidal soap (NL)

Isaria (paecilomyces) fumosoroseus (NL)

Lambda-cyhalothrin (L)

Malathion (L)

Metarhizium anisopliae (robertii) (NL)

Neem oil (NL)

Permethrin (L)

Pymetrozine (NL)

Pyrethrins+piperonyl butoxide (L)

Pyrethrins+sulfur (NL)

Pyridaben (NL)

Pyriproxifen (eggs) (L)

Spinetoram+sulfoxaflor (N)

Spiromesifen (L)


Active ingredients that may be applied systemically include: abamectin (injection), acephate (injection), azadirachtin (injection, soil drench), clothianidin (soil drench), cyantraniliprole (soil drench, soil injection), diflubenzuron (sprench), dinotefuran (soil drench), imidacloprid (soil drench), metarhizium anisopliae (robertii) (NL), and neem oil (soil drench).

Make insecticide applications after bloom to protect pollinators. Applications at times of the day and temperatures when pollinators are less likely to be active can also reduce the risk of impacting their populations.

Note: Beginning July 1, 2022, neonicotinoid insecticides are classified as state restricted use for use on tree and shrub insect pests in Massachusetts. For more information, visit the MA Department of Agricultural Resources Pesticide Program.

Read and follow all label instructions for safety and proper use. If this guide contradicts language on the label, follow the most up-to-date instructions on the product label. Always confirm that the site you wish to treat and the pest you wish to manage are on the label before using any pesticide. Read the full disclaimer. Active ingredients labeled "L" indicate some products containing the active ingredient are labeled for landscape uses on trees or shrubs. Active ingredients labeled "N" indicate some products containing the active ingredient are labeled for use in nurseries. Always confirm allowable uses on product labels. This active ingredient list is based on what was registered for use in Massachusetts at the time of publication. This information changes rapidly and may not be up to date. If you are viewing this information from another state, check with your local Extension Service and State Pesticide Program for local uses and regulations. Active ingredient lists were last updated: January 2024. To check current product registrations in Massachusetts, please visit: .