Crapemyrtle Bark Scale Research Articles

Thermal Tolerance and Prediction of Northern Distribution of the Crapemyrtle Bark Scale (Hemiptera: Eriococcidae).

Physiological limits of non-native species to environmental factors are critical for their establishment and spread in the adventive range. The crapemyrtle bark scale, Acanthococcus lagerstroemiae (Kuwana), is a major pest of crapemyrtles. Despite concerns on its rapid spread, there is a lack of information on potential distribution range of this scale in the United States. To understand this scale's distribution potential, its thermal tolerance was evaluated using higher and lower thermal limits. Exposure time leading to 50 and 90% mortality (Lt50 and Lt90) at extreme low or high temperatures were measured under controlled conditions. A model was then built to fit temperature data of cold fronts from 2001 to 2016 and to calculate potential mortalities along latitudes. Isothermal lines delineated at 90% mortality were defined as the northern limits. Modeling results suggested that A. lagerstroemiae nymphs collected in summer could tolerate heat; however, they were more susceptible to cold temperatures. Laboratory assays suggested that cold tolerance of A. lagerstroemiae nymphs varied from summer to winter. For example, SCP of nymphs collected in summer was higher than those collected in fall (-21 vs. -27°C), and the exposure time leading to Lt90 at 0°C was also different, which were 8 versus 50 h comparing nymphs collected in summer versus fall. Our prediction suggested that A. lagerstroemiae is likely to be limited by cold temperatures along the 43° N latitude. Based on these results, integrated management strategies can be developed for A. lagerstroemiae within the predicted range.

Insecticidal Control of Crapemyrtle Bark Scale on Potted Crapemyrtles, Fall 2018

Insecticidal Control of Crapemyrtle Bark Scale on Potted Crapemyrtles, Fall 2018

Hypericum kalmianum (St. Johnswort) Confirmed as a New Host of the Crapemyrtle Bark Scale in Virginia, U.S.A.

Hypericum kalmianum (St. Johnswort) Confirmed as a New Host of the Crapemyrtle Bark Scale in Virginia, U.S.A.

Physiology of crapemyrtle bark scale, Acanthococcus lagerstroemiae (Kuwana), associated with seasonally altered cold tolerance

Temperature is one of the most important abiotic factors influencing the adaptation and diversification of insects. Diverse and complex physiological mechanisms have evolved to help insects adapt to seasonal changes in temperature and prevent cold injury. Although the mechanisms of seasonal adaptation to low temperatures have been studied for insects in different taxa, none of these mechanisms have been investigated in scale insects in the superfamily Coccoidea. The crapemyrtle bark scale, Acanthococcus lagerstroemiae (Kuwana) (Hemiptera: Eriococcidae), is a newly introduced scale pest of crapemyrtles, Lagerstroemia spp. (Myrtales: Lythraceae). Our previous study concerning the cold tolerance of this pest suggested that, from summer to winter, A. lagerstroemiae seasonally adapted to lower temperature with a 5 °C reduction of supercooling points. In addition, time required to achieve the same levels of mortality at lower temperatures also increased. In this study, we used A. lagerstroemiae as a model system to investigate the physiological mechanisms correlated with changes in cold tolerance in scale insects, by measuring water content, lipid content and fatty acid composition, and cryoprotective polyols and sugars every other month. Results suggested that water content was lower in winter and early spring than in summer and early fall (40.8% vs. 63.3%). The proportions of the fatty acids in PL were similar over seasons, but in TAG, shorter chain fatty acids (from C6:0 to C10:0) increased in winter as longer chain fatty acids (from C14:0 to C18:0) decreased. Among all measured polyols and sugars, including glycerol, d-mannitol, myo-inositol, and d-trehalose, the levels of d-mannitol were the highest in January 2016, which were 19-times of those in March 2016 and 4.5-times of those in September 2016. Results from this study provide a better understanding on how A. lagerstroemiae overwinters, which may give insights into the overwintering strategies of other scale insects.

How scary is this? Two emerging pests: emerald ash borer and crapemyrtle bark scale©

How scary is this? Two emerging pests: emerald ash borer and crapemyrtle bark scale^©

Crapemyrtle Bark Scale Acanthococcus (=Eriococcus) lagerstroemiae (Kuwana) (Insecta: Hemiptera: Eriococcidae)

The crapemyrtle bark scale is an invasive felt scale in the family Eriococcidae (or Acanthococcidae, as the taxonomy of this family is still being debated). This group is in the superfamily Coccoidea (scale insects) and the order Hemiptera (true bugs). Felt scales, also called bark scales, are not considered either armored scales or soft scales. As of early 2018, crapemyrtle bark scale has not yet been reported in Florida, however, it has been found in Alabama and Georgia and is expected eventually to spread into Florida. At that time, early detection and treatment will be critical to minimize further spread within the state. Includes: Introduction - Synonymy - Distribution - Description - Life Cycle and Biology - Hosts - Damage - Management - Selected References.https://edis.ifas.ufl.edu/in1218
 Previously published at http://entnemdept.ufl.edu/creatures/ORN/SCALES/crapemyrtle_bark_scale.html

Erratum to: “Bark and Systemic Insecticidal Control of Acanthococcus (=Eriococcus) lagerstroemiae (Crapemyrtle Bark Scale) on Landscape Crapemyrtles, 2016”

Erratum to: “Bark and Systemic Insecticidal Control of Acanthococcus (=Eriococcus) lagerstroemiae (Crapemyrtle Bark Scale) on Landscape Crapemyrtles, 2016”

Longevity of Imidacloprid as a Soil Treatment for Crapemyrtle Bark Scale on Crapemyrtle, 2016–2017

Longevity of Imidacloprid as a Soil Treatment for Crapemyrtle Bark Scale on Crapemyrtle, 2016–2017