Gardening

Cypress aphid



It is an aphid lacnid, which attacks several conifers belonging to the Cupressaceae family. Cupressus arizonica, C. macrocarpa, C. sempervirens, Juniperus phoenica, J.oxycedrus macrocarpa, J.sabina, Chamaecyparis lawsoniana, Tuja orientalis and Cupressociparis leilandii are susceptible.
Particularly attached are the plants of C. arizonica bred to form hedges, as the frequent pruning, irrigation and fertilization stimulate the vegetative development of the plants, making them more susceptible to infestations of the aphid.
Due to the removal of the sap and the presence of toxic substances injected with saliva from the phytomizo in the plant tissues, reddening and vegetative desiccation occur, first located in the inner part of the plant, fresher and shaded, and then spread along vertical strips of vegetation, finally affecting the entire crown.
The remarkably attached plants end up almost completely drying up, except in the upper part where you can sometimes observe sparse vegetative spikes. The vitality and ornamental function of plants so damaged are in many cases seriously compromised.
The bark beetles, taking advantage of the state of debilitation, settle in the immediately following times. Their prolific and larval tunnels dug into the cortex truncate the lymphatic vessels, further accentuating the deterioration of the plants, which often becomes irreversible also due to the establishment of the Cypress Cancer, which then leads the plant to death.

Biological cycle



Cinara cypresses lives for the entire year on well lignified twigs, sometimes forming thick colonies arranged in a sleeve. During the good season it multiplies with the almost uninterrupted succession of generations of females landing virginopare, with appearance of the winged forms in May-June.
The colonies reach the maximum density in spring and autumn, after the first late summer rains allow the emission of new vegetation. In summer and winter the aphid populations are reduced, being sensitive to high and low temperatures. Winter is overtaken by female virginal-endangered females, sheltered in the innermost part of the canopy and already during the month of February colonies are in full development.

Cypress aphid: Defense


the development of the aphid colonies is slowed by predatory entomophages, including larvae of sylphid diptera (episyrphys balteatus, in particular), as well as by larvae and adults of coccinellid beetles and chrysopa larvae.
however, due to the considerable dangerousness of this aphid, careful monitoring of the plants is necessary in order to carry out the fight promptly, when the first outbreaks of infestation are noticed.
the most suitable periods for interventions are those of late winter-early spring and late autumn, coinciding with the plant's release of new vegetation and the consequent reconstitution of aphid populations. in general only one intervention is sufficient, provided that the inner parts of the canopy are reached, where the aphids are well sheltered;
to facilitate the penetration of the insecticidal mixture, it would be advisable to make an adequate pruning thinning before the treatment.
The active ingredients that can be used are; acephate, etiofencarb, deltamethrin, flucitrinate, alfamethrin and pirimicarb.