Phylloxera, the pest that caused the destruction of much of the world’s grape vines in the late 19th century, has appeared for the first time in Washington’s leading wine region of Walla Walla.
Walla Walla is located in the south-eastern corner of America’s Washington State. Many winegrowers in the region have vines planted on their own rootstocks rather than grafted onto phylloxera-resistant ones, with Walla Walla’s winters considered too cold and its soil too sandy for the pest to thrive.
The region's warming climate, however, might be one of causes that led to the outbreak. Walla Walla hasn’t had the hard winter freezes that would have normally slowed down phylloxera's reproduction.
President of Washington State Wine Steve Warner told Imbibe that he couldn't comment on the effect of climate change, yet assured that ‘while we don’t yet know the scope [of the outbreak], we do know vineyards can remain productive for years with careful management’.
It's not all bad news though. Phylloxera feeds on the roots of the plant, causing wounds that lead to infections, severely reduced yields, and eventually the death of the vine. Until this happens however, phylloxera has no negative effects on the quality of the wine.
‘We don’t foresee an impact to the consumer, as phylloxera does not affect wine quality,’ said Warner. ‘Our growers will address any vineyard productivity issues over time, to ensure our future generations have world-class grapes to work with. The great majority of the world’s wine regions have managed this pest, and we will too.’