A Guide to Grapevine Abnormalities in South Africa - P.G. GOUSSARD

Quince stem-borer pupa (341); stem-borer (342).

PHOTO 341. A typical example where a longitudinal section of this affected trunk exposes the presence of a quince stem-borer pupa. Also note the incidence of tunnels and wood shavings, with which this pest phenomenon is associated.

PHOTO 342. Although stem-borer damage is mostly encountered in wood that is older than a year, younger canes may also be affected – as indicated in this example by small, almost invisible holes.

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