Landscape - Southern Red Mites

Watch for increased southern red mite activity as cooler weather continues. The following is more information.

Southern red mite adults and nymphs are active from 1913 -3518 [2933 peak] and 240 -3584 [3034 peak] GDD base 50 respectively. This mite feeds azaleas, camellias, hollies, photinia, and many others. Southern red mites generally feed on the underside of leaves causing them to turn brownish to grayish and damaged leaves may drop prematurely. This mite is dark red to brownish and has a pale stripe. Eggs are brownish to reddish and have a fine hair coming off the center.

Southern red mite highly magnified. Photo by Jim Baker, North Carolina State University, Bugwood.org

Information from Brian Kunkel, Ornamental IPM Specialist, UD

Landscape and Nursery - Cool Season Mites

The following is information on cool season mites in the landscape. These mites will be more active now with the reduced temperatures.

COOL SEASON MITES.

As temperatures consistently return to the 60's and 70's during the next few weeks, spruce spider mite and southern red mite activity will increase. Spruce spider mites feed on fir, arborvitae, spruce, Douglas-fir, and other conifers, feeding on older foliage first. Spruce spider mites are olivedark red with reddish-yellow legs and two reddish eye spots with a pale stripe down the back (visible with a microscope). Spruce spider mites start feeding in the fall around 2301 3957 [3094 peak] GDD and continues until there is a hard frost. In the summer, damage appears as bleaching, yellowing, stippling or bronzing of the needles. Damage visible on trees in summer is from intensive fall feeding.

Southern red mites feed on a wide variety of plants including azaleas, camellias, hollies, clethra, juniper, elaeagnus, hibiscus, photinia and rose. Nymphs and adults are active starting around 2401 3584 [3034 peak] GDD and 1913 3518 [2933 peak] GDD respectively. This mite has a dark reddish to brown abdomen with a pinkish to red cephalothorax and a pale mid-stripe. It feeds on the lower leaf surface but during high populations may be found on upper surfaces. Damaged leaves may be brown to gray and drop prematurely.

Monitor with a clipboard and a white sheet of paper, looking for dots the size of periods. Watch for predatory mites and small lady beetles; both are predators of the spruce spider mite and should be conserved. Miticides available for control include hexythiazox (Hexygon, Savy), bifenazate (Floramite), abamectin (Avid) and others. Research has shown bifenthrin (Talstar) can cause mite 'resurgences' because natural enemies are killed; thus mite eggs are able to hatch without threat of predators.

Information from Dr. Brian Kunkel, Ornamental IPM Specialist, UD

Landscape and Nursery - Southern Red Mites

Southern Red Mites, Oligonychus ilicis have hatched and are very active. The following is information on these mites from the University of Maryland.

Southern red mites are active at this time. Examine broadleaf evergreens including hollies, laurels, camellias, and azaleas. The southern red mite is also commonly found Clethra, Photinia, Pyracantha and Viburnum. If your customers have ornamental or fruit bearing plums and peaches, southern red mite is active on these plants also.

Control: Early in the season some of the best control measures involve using mite growth regulators that impact nymphs of spider mites. These materials prevent mites from shedding their skin and going to the next life stage. Here are some of the mite growth regulators available: hexythiazox (Hexygon), clofentezine (Ovation), etoxazole (Tetrasan). Another miticide that is relatively new that looks very good is Forbid. The chemical in Forbid is translaminar and desiccates treated mites and eggs. It acts a little like a growth regulator in that it inhibits molting of the mites. It also inhibits oviposition in adult females. Some of the other materials for mite control are abamectin (Avid) fenpyroximate (Akari), bifenazate (Floramite), spinosad (Conserve), and pyridaben (Sanmite).

Information from the TPM/IPM Weekly Report for Arborists, Landscape Managers & Nursery Managers from the University of Maryland Cooperative Extension

Landscape and Nursery - Southern Red Mite

This is the time of the year that Southern Red Mite (Oligonychus ilicis) is out and active. The following is an article on this pest.

Southern red mite. Photo by John A. Weidhass, Virginia Polytechnic Institute and State University, Bugwood.org

Be on the look out for southern red on Japanese holly, camelia, laurel, azaleas, and pyracantha. You may be able to find eggs, immature mites and some mature mites. This mite is one of the most destructive mites of broad leaved evergreen plants. It feeds using piercing mouthparts to damage plant cells and causes a stippling to the foliage that can be noticed as the population increases. Examine foliage of plants in hot, sunny locations for mite activity. Dry wather will increase activity of this mite.

Monitoring: Examine the undersides of foliage of Japanese holly, camellia, laurel, azaleas, and pyracantha. These guys are small so you may want to beat foliage over a white piece of paper and look for small reddish “spots” crawling around.

Control: Since southern red mite just hatched you have the options of using mite growth regulators such as Hexygon. Most arborists mix 1 % horticultural oil with Hexygon. Other good materials to use include Forbid, Akari, Floramite, or Avid.

Information adapted from an article in the May 12, 2006 edition of the TPM/IPM Weekly Report for Arborists, Landscape Managers & Nursery Managers from the University of Maryland Cooperative Extension

Ornamentals Hotline Pictures for the "What's Hot" Section of Issue 26, October 12, 2007

Brown marmorated stinkb bug adults and nymph.

Photo by Gary Bernon, USDA APHIS, Bugwood.org

Western conifer seed bug.

Photo by Whitney Cranshaw, Colorado State University, Bugwood.org

Southern red mite.

Photo by John A. Weidhass, Virginia Polytechnic Institute and State University, Bugwood.org

Spruce spider mite with webbing.

Photo from USDA Forest Service - Region 4 Archive, USDA Forest Service, Bugwood.org