Evergreen Pests & Fire Blight

Fire Blight

• Fire blight is a devastating disease cause by the bacteria Erwinia amylovora. Evergreens belonging to this plant family include thorny shrubs from the genus Pyrachantha and the evergreen pear tree (Pyrus kawakamii). Fire blight starts by infecting the plant's flowers resulting in a water-soaked effect that turns blossoms a gray-green tone. The flowers soon turn to a brown-to-black hue that quickly spreads to new shoots and foliage. Fire blight gives plants the appearance of being scorched. Eventually, the plant's fruit emits tacky black bacterial ooze. Controlling this disease begins with limiting the spread by maintaining a method of managing pests.

Aphids

• Aphids have a small, soft body coupled with lengthy, thin mouths used to pierces tender plant parts, such as leaves and stems. Apple aphid (Aphis pomi) is a species from the Aphidae family originating from Europe and reported in the United States in 1849. The light-green females have a pear shape and no wings, while the smaller, yellowish- brown males have long, black antennas. Bean aphids (Aphis fabae Scopoli) are dark green-to-black insects with white appendages. These pests appear in subtropical and temperate regions throughout the world. Applying aphicides to foliage before trees blossom early in the season helps control aphids.

Leafhoppers

• Leafhoppers are an insect species of the Cicadellidae family. These piercing-and-sucking pests use their mouthparts to ingest plant fluids. Cherry leafhopper (Fieberiella flonii) is a deep-brown pest with a shape and tone resembling their host plant's buds. The bright-green nymphs overwinter on pyracantha plants. The redbud leafhopper (Enchenopa bistrata) is an insect variety with a black body and yellow splotches. This evergreen plant pest has a pearlike shape and the appearance of a flower bud. Leafhopper control methods include spraying plants with insecticides during March to early April for overwintering nymphs and again in June for hatching nymphs.

Pear psylla

• Pear psylla (Cacopsylla pyricola) is an insect species that feed on new plant growth on the evergreen pear tree (Pyrus kawakamii). This North American pest first came to the United States via Connecticut in 1832 and since then spread as far as Washington state. The stages of the pear psylla follow this pattern adult --- egg, small nymphs and large nymphs. Pear psylla adults come in two varieties: a dark reddish-brown larger insect and during the summer, a tan to light brown-bodied adult. Nymphs start out as a flat, oval red-eyed, yellow-bodied insect that become progressively larger. Insecticides help control pear psyllas.