Monday, May 5, 2014

Pest News for Week of May 5th


From: Steve Frank, Extension Entomologist

Cool Season Mites

In North Carolina, the most important cool season mites are the spruce spider mite (Oligonychus ununguis) and southern red mite (Oligonychus ilicis). These are among the earliest and most damaging pests in nurseries and landscapes. As their name implies, cool season mites are active in spring and fall when they suck fluid from cells on plant leaves and needles. In hot summer months these mites are dormant. However, it is summer when their damage becomes apparent as chlorophyll bearing cells die. Thus, by the time plants exhibit aesthetic damage the mites are gone and treatment is wasted.

Southern red mite feeds on broadleaf evergreens such as azalea, camellia, holly, and rhododendron. Spruce spider mite feeds on coniferous evergreens such as spruce, juniper, hemlock, and arborvitae.

Scout plants that had mites or mite damage the previous year as they are likely to have them again because the mites have overwintered as eggs. Cool season mites reproduce very quickly so it is important to identify populations early before they reach eruptive levels and cause severe damage. Throughout spring you will find egg, juvenile, and adult mites due to their rapid, overlapping generations. In addition, you may find silk webbing and shed skins. On broadleaf evergreens, look on the underside of leaves for the southern red mite. Look for spruce spider mite on conifers by inspecting last year’s needles.

The most efficient method of scouting for cool season mites (and other mites) is to hold a piece of white paper or a paper plate below a branch and strike it with a pencil or stick to dislodge arthropods. Spider mites will appear as tiny moving specks about the size of the period at the end of this sentence.

For more information and control options consult the North Carolina State University insect note at More pictures and information on southern red mite at

Southern red mite on cherry laurel. Photo: S. D. Frank.

Tulip Poplar Aphids in the Landscape

Tulip poplar aphids are becoming abundant in their annual cycle of boom and bust. They start to boom in spring since natural enemies are not very active or abundant. As aphids become abundant, predators and parasitoids home in on them and tend to keep their numbers under control. However, trees in highly urban areas or those tended by fire ants may become more abundant since nature predation and parasitism will be limited. General information about managing aphid in the landscape is here. Other aphids to watch out for soon are crape myrtle aphids and rose aphids.

Lady beetle eggs positioned next to a family of tulip poplar aphids. Photo: S. D. Frank.

Fire Ant Mounds Abound

Fire ants are making lots of fresh new mounds this time of year. Often like this one pictured they develop in just a day or so. A frequent location for fire ant mound is in the mulch around landscape trees, particularly when too much mulch is applied as shown in this video (


Recommendations for the use of chemicals are included in this publication as a convenience to the reader. The use of brand names and any mention or listing of commercial products or services in this publication does not imply endorsement by North Carolina State University, North Carolina A&T State University or North Carolina Cooperative Extension nor discrimination against similar products or services not mentioned. Individuals who use chemicals are responsible for ensuring that the intended use complies with current regulations and conforms to the product label. Be sure to obtain current information about usage regulations and examine a current product label before applying any chemical. For assistance, contact an agent of North Carolina Cooperative Extension.
Employment and program opportunities are offered to all people regardless of race, color, national origin, sex, age or disability. North Carolina State University, North Carolina A&T State University, U.S. Department of Agriculture, and local governments cooperating.

For more information contact your local Cooperative Extension Center and ask for the Commercial Horticulture Agent.