(Courtesy of and adapted with modifications from the University
of Wisconsin) Under most conditions, insects are not perennially
serious pests of currants and gooseberries; however, certain
insects occasionally will become abundant enough to cause
serious damage if left uncontrolled. The currant aphid,
Cryptomyzus ribis (L.), overwinters in the egg stage on plant
stems. Eggs hatch in early spring, and the insects feed by
sucking out the plant juices, which results in stunted and
distorted new growth. As leaves continue to develop, they will
be crinkled with downturned edges. Areas between veins on the
upper leaf surface may be reddened. As the aphids feed, they
excrete excess sugar and water in small droplets called
honeydew. Ants may feed on this, and a black fungus (sooty
mold)often grows on it. The aphids themselves are small (up to
about 2 millimeters), green, and usually found in colonies.
Other aphid species also occasionally feed on currants and
gooseberries. Aphids often are kept under good natural co