Short History of Grape Phylloxera

"Grape stock prices would reach an all-time high, and wine would be in short supply. The poor and the middle-class turned to absinthe as a cheaper alternative"

Phylloxera was without a doubt the greatest threat to vineyards. Inadvertently imported to England and France on nursery stock between 1854 and 1860, the insect quickly invaded nonresistant Vitis vinifera wine grape blocks throughout Europe. By the end of the 19th century, grape phylloxera had destroyed two-thirds of the vineyards on the continent. When it was first discovered, it was called Phylloxera vastatrix - "the devastating louse".

The losses suffered in France as a result of the phylloxera invasion in the 1860s was considered being greater than the total cost to the French of the Franco-Prussian war. Over 2000 hectares of vineyard were wiped out in France before the reconstruction on phylloxera-resistant rootstocks began.

Since that time, this pest has invaded most of the grape growing areas of the world. Grape phylloxera was introduced into California in the 1850s, where it currently infests an estimated 20% of the vineyards.

The British Columbia Department of Agriculture found grape phylloxera in the Penticton area in 1961; growers discovered the insect in Oregon in the early 1970s.

In Australia, phylloxera was first discovered in Victoria in 1875. The Victorian government attempted to eradicate the pest by destroying vines and sterilising the soil. This was very expensive, and proved to be unsuccessful. It spread to Rutherglen in 1899, which at the time was the principal vine-growing district in the country. It has never recovered this status since the setbacks it suffered as a result of the phylloxera infestation (although it is still a premium winegrape-producing region). Once the government realised that it was futile to continue eradication efforts, money was redirected to helping the growers replant their vineyards with grafted vines.

In New Zealand it has been present in the North Island since the the end of the 1800's. Romeo Bragato found it on his travels in 1895 and lamented its presence. It remained North Island bound until the 1990's when it found its way to Malborough devastating the vineyards there and forcing the replanting of most the region on resistant roostocks. So far it is not known in Canterbury or Otago where a large proportion of vineyards have vines planted on their own roots and would be immediately susceptible to the disease should it find its way to these regions. It would be devastating for these vineyards to have Phylloxera introduced.

What is Grape Phylloxera

Grape phylloxera is a tiny aphidlike insect that feeds on Vitis vinifera grape roots, stunting growth of vines or killing them. Grape phylloxera damage the root systems of grapevines by feeding on the root, either on growing rootlets, which then swell and turn yellowish, or on mature hardened roots where the swellings are often hard to see.

The majority of grape phylloxera adults are wingless females. They are generally oval shaped, but egg layers are pear shaped. They are small (0.04 inch long and 0.02 inch wide) and vary in color from yellow, yellowish green, olive green, to light brown, brown, or orange. Newly deposited eggs are yellow, oval, and about twice as long as wide. Nymphs resemble adults except they are smaller.