01/25/00 Southern Pine Beetle in Hernando, Volusia, and Levy Counties

John L. Foltz (retired)
University of Florida
Department of Entomology & Nematology
James R. Meeker (retired)
Florida Department Agriculture & Consumer Services
Division of Forestry

Active Southern Pine Beetle (SPB) infestations were discovered in Hernando, Volusia, and Levy counties. Active infestation continue along the Suwannee River in Hamilton, Madison and Suwannee counties. More information about these infestations, the benefits of controlling SPB spots during the summer, and a URL for SPB web pages are included below.

Hernando - On August 16, eight active SPB infestations were confirmed near Hwy 41 in the southern portion of the city of Brooksville. Infestations ranged in size from 5 trees to 20 acres with several spots larger than one acre. Most infestations are in or near residential/commercial areas and all appear to involve relatively mature, unmanaged natural stands of loblolly pine. A subsequent aerial detection flight and ground checks found a total of 21 spots affecting approximately 53 acres. All activity appears to be confined to a 3 mile square area. Local Division of Forestry (DOF) personnel are aggressively informing and assisting landowners and local governments, and are the contacts for more detailed and timely information. Control/salvage harvest operations are underway on some of the infestations. Interestingly, these infestations represent the southernmost extent of SPB ever recorded in the state.

Volusia - Steve Miller with St. John's Water Management District reported a 25+ acre active infestation of SPB just south of Crescent Lake in northwestern Volusia County. The infestation is in a mature, bottomland loblolly pine-hardwood stand. Control/salvage harvesting of this spot is underway. An aerial survey of the surrounding areas revealed no other signs of SPB.

Levy - A possible third new SPB warning may be forthcoming for the coastal area of southern Levy County. A variety of suspicious activity has just been reported but as yet has not been satisfactorily diagnosed. A recent aerial detection flight revealed 80 suspect spots in one area, the largest being 6 separate spots of 100+ trees. In addition, one multi-acre spot may exist near Yankeetown. A ground check of some of the spots on August 26 suggested that many of the small spots are inactive with SPB brood having matured and dispersed. Several large spots still have active trees, but spot growth is declining. Until further notice a "watch" situation is posted for SE Levy County.

Hamilton, Madison and Suwannee - The existing "warning" situation for SPB along the Suwannee River is still in effect. To date a total of 59 infestations have been detected in the area (28 in Hamilton County, 24 in Madison County and 7 in Suwannee County), of which 16 (27%) have been controlled. Of the 43 existing infestations, 31 (72%) are less than 1 acre in size. Despite the relatively high level of localized activity, infestations are still too few and too small for the area to be classified as a severe "Outbreak" situation.

Population Management - In all of these locales, now is the time to urge and emphasize control of active infestations, before problems potentially worsen dramatically. Typically, SPB activity slows down and there is a reduced likelihood of both dispersal and successful initiation of new spots during the hot summer months. We now have a somewhat brief window of opportunity to successfully influence future events because infested trees and beetle populations are: 1) readily detectable, 2) relatively constant and confined (i.e., they are not continually/consistently generating new spots) and 3) seasonally declining or expanding at a slow rate. During the fall when conditions are more favorable for SPB development and dispersal, it will be much more difficult to find and control new infestations.

The UF/IFAS Pest Alert WWW site is at: http://entomology.ifas.ufl.edu/pestalert/