Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract Full Text

First report of scale insects as pests of Kangra tea in Himachal Pradesh, India.


A field survey was conducted in Palampur (Himachal Pradesh, India) and neighbouring tea gardens to study the infestation of scale insects in tea. To determine the incidence of scales in the experimental plot (50 sq. m), 10 tea bushes were randomly selected for sampling. The number of scale insects (egg mass and crawlers) was counted on 10 randomly selected leaves and stem (10 cm length) per bush and represented as number of egg mass per leaf and stem. The infestation of the scales (egg mass) was first observed during April (1-2 egg mass per leaf), then the infestation gradually increased during May (3 and 5 egg mass per leaf and stem, respectively) and June 2012 (4 and 10 egg mass per leaf and stem) and peaked during July (8 and 13 egg mass per leaf and stem), which may due to high temperature (28-30°C) and humidity (70-80%). Three soft scale (Coccidae) and one armored scale (Diaspididae) species were observed during April-July 2012. These were: the green scale (Coccus viridis), hemispherical scale (Saissetia coffeae), brown soft scale (Coccus hesperidum), and the yellow scale (Aonidiella citrina). This is thought to be the first report of the incidence of these scales on tea in Palampur. Additional information is given on crop damage due to these pests, their geographical distribution, host range and morphology.