Leyland cypress, aphid, dieback, browning, hedge, trimming
Leyland and Lawson cypress are extensively used to make quick growing hedges, but regular trimming of the hedges is needed to avoid excessive growth. Brown patches (dieback) are becoming more common on trimmed hedges. Feeding damage by conifer aphids can cause browning on conifers, but it is uncertain if aphids are responsible for most of the damage seen.
To survey the relationship between incidences of dieback in Leyland and plants’ growing environment and style of maintenance. To understand whether the attack of cypress aphid, Cinara cupresivora, is the primary cause of foliage dieback in Leyland hedges.
The findings of this project will provide answers on how the maintenance of the Leyland hedges can be optimised to decrease the likelihood of cypress dieback appearing and spreading.
Read more on Conifers: brown patches
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