Dr. Kris Braman
Professor of Entomology
The University of Georgia
There are several types of insects that seem to like paspalum in
Protection of pollinators:
Managed landscapes often contain flowering plants and can be important foraging sites for bees and other pollinators. Many insecticides are extremely toxic to bees, and others can affect colony health with repeated exposure. Use extreme care when applying insecticides to flowering plants, including
Infestations of the following insects have been documented in seashore paspalum.
Females lay egg clusters on grass blades, other green plants, twigs, fences, sides of buildings, or any light colored object near turf. Eggs hatch in 7-10 days during cool weather and in 2-3 days during hot weather. Larvae mature in about 12 days during summer and 4 weeks during cool weather. Older larvae will pupate in the soil, and new moths will emerge in 9-20 days depending on temperature. Only 23-28 days required to complete a generation during mid-summer.
Scrap underside of leaf blades, leaving a clear upper skeletal epidermal layer; chew leaf margins, leaving a tattered look. Large larvae will eat all leaf material down to
Spinosad (CONSERVE, IRAC Group 5) is
Eggs are laid between leaf sheaths and hatch in 4-5 days. Young larvae burrow into grass stems, feeding and tunneling. Large larvae will burrow out and feed on the crown. 1-2 generations per year.
Stems turn straw colored and die in a scattered fashion. Can feed on roots, crowns, and stolons. Turf will easily pull up.
Avoid stress-induced root or crown damage with sensible irrigation and fertilization.
Biological control—Fungus Beauveria and parasitic nematode (Steinernema
tropical sod webworm
Life cycle: eggs hatch in about one week at 78 F (26 C). Larvae complete development in about 25 days.
Feed along midrib, between veins. Will chew notches in the leaf blades, giving a ragged appearance. Infested turf appears to be severely scalped, with large yellowish or brown patches.
Spinosad (CONSERVE, IRAC Group 5) is
Overwinter in thatch, behind leaf sheaths, or in stems. Eggs hatch as turf comes out of dormancy. Newly hatched nymphs seek moist, humid feeding sites near the base of grass plants. As they feed, they excrete a frothy spittle mass for protection from desiccation and enemies. Masses are found just below the soil surface (0-5 cm). Nymphs mature as adults in 34-60 days depending on moisture and temperature. Eggs hatch in 2-3 weeks during mid-summer. Generally 2 generations per year.
Adults and nymphs suck juice from the grass, weakening the plant. Adults inject a salivary toxin that is translocated up and down the stem, cause the whole plant to turn yellow and brown, then the grass dies. Sparse, blighted looking turf.
Most abundant in years with high spring and summer rainfall. Damage resembles chinch bug feeding except that it occurs in shady areas rather than full sun. Young spittlebugs cannot survive under dry conditions and thrive in moist thatchy turf. Withhold irrigation when nymphs are hatching in the spring or midsummer. Dethatch and aerate to reduce spittlebug buildup.
Chemical control: Acephate (ORTHENE)
Spend most of their lives underground. When
chemical control is best during mid-summer when crickets and nymphs are small.
Chemical control: imidacloprid (MERIT, Group 4A) clothianidin (ARENA 4A) applied at the beginning of egg hatch, subsurface application of fipronil (CHIPCO CHOICE, Group 2B). Carbaryl bait (Group 1A). Apply late in
Biological control: parasitic wasp—Larra bicolor parasitic nematodes—Steinernema
Eggs hatch in 2-3 days. At 75 F (23.9 C), adulthood is reached in 7-10 days. Very tolerant of high summer temperatures. Prefer droughty conditions.
Feed underneath leaf sheaths. Grass appears weak and
Irrigation to minimize drought stress.
Chemical control: Carbaryl may provide some suppression, no effective miticides are labeled
Grubs feed on
Vigorous turf may support as many as 20 grubs/Ft2 while stressed turf can be injured by 8-10 grubs/ Ft2. Successful management requires targeting the small (first and second instar) grubs.
Biological control: Several predators and parasitoids although none commercially available. Entomopathogenic nematodes Heterorhabditis
Chemical control: Carbaryl and pyrethroids are excellent for Green June beetle larvae only. Curative control of larger grubs requires trichlorfon (DYLOX, Group 1B). Systemic insecticides such as imidacloprid (MERIT) and clothianidin (ARENA, Group 4A) are effective if applied early in the life cycle. Chlorantraniliprole (ACELEPRYN, GROUP 28) is also effective against caterpillars. Combination products imidacloprid +bifenthrin (ALLECTUS, Group 4A + 3A) and clothianidin + bifenthrin (ALOFT, GROUP 4A + 3A) are also available.