Myllocerus sp. nr chloris Crops: Apple, peach Why is it a problem? Adults feed in groups on small apples, causing rot and making them unmarketable. They can arrive in large numbers. However, as they normally feed in groups total fruit loss is generally quite low and they can be relatively …
Microserica sp. Crop: Apple Why is it a problem? Large beetle numbers can defoliate trees. This is mainly a problem with young trees and newly established orchards where it can retard growth. Where and when is it a problem? Problems have been recorded in Thimphu and Paro valley from late …
Linda rubescens Crop: Apple Why is it a problem? Larvae bore into stems causing twig dieback. This is most damaging in seedlings where the main leading shoot can be destroyed. Outbreaks are very easily managed without pesticides, provided trees are monitored. Where and when is it a problem? Outbreaks are …
Eriosoma lanigerum Crop: Apple Why is it a problem? The woolly aphid is a very conspicuous pest on trees of all sizes, but is mostly a problem on small trees on which it can stunt growth. Galls can also cause splitting and secondary infections, and root galls can affect nutrient …
Diaspidiotus perniciosus Crop: Apple Why is it a problem? When feeding on apples this scale insect leaves red spots, and in severe cases distorts the fruit. This affects sale prices, especially for export. Complete coverage on twigs and branches can lead to dieback of affected parts and ultimately the decline …
Cleorina spp. Crops: Apples, walnut Why is it a problem? Cleorina leaf beetles are not normally a serious problem in apples, but can cause localised damage to developing apples and occasionally completely defoliate young trees. Where and when is it a problem? This beetle can be commonly found in all …
Argyresthia sp. Crop: Apple Why is it a problem? Caterpillars burrow into developing apples, resulting in early fruit fall and lost production. It is difficult to manage. Where and when is it a problem? It can be a serious problem in most high altitude apple growing areas (> 2,000 m …
Agalope hyalina Crop: Apple Why is it a problem? Large numbers of larvae on young fruit can result in considerable losses through fruit drop. Market value can also be reduced through distortion of fruit shape caused by partial feeding on the apple. Insecticides are needed to manage severe outbreaks. Feeding …
Rhynchocoris poseidon Crop: Citrus Why is it a problem? Feeding on sap of young mandarins can cause considerable early (“summer”) fruit drop, although compensatory development of remaining fruit can lessen the economic importance. Damage can be severe, but management is generally not needed in most years and orchards. Where and …
Phyllocnistis citrella Crop: Citrus Why is it a problem? The citrus leaf-miner is mainly a problem in young (seedling) trees, including in nurseries, where at high densities it retards growth and can result in secondary infections. Mature trees are better able to withstand the attack. Where and when is it …
