How to Manage Pests

Grape phylloxera—Daktulosphaira vitifoliae

Phylloxera are tiny yellow soft-bodied insects that feed in groups on roots especially in summer and fall. They are oval and less than 0.10 inch long; a hand lens is required to see them.

Life cycle

Damage

Phylloxera cause a premature yellowing of leaves and stunted growth. Root tips are swollen with yellow brown galls. Roots may be dead or dying.

Symptoms

There are no satisfactory controls available once vines are infested. Good irrigation and fertilizer practices help offset damage to roots. Use resistant rootstocks.