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NivEflsfflSSiraiitfTi Georgia Forestry Commission Forest Health Fact Sheet FORESTPEST MANAGEMENT GEORGIAFORESTRY COMMISSION SOUTHERN PINE BEETLE CONTROL TECHNIQUES DEFINITIONS Southern pine beetle (SPB) caused timber losses can be reduced through the use of one or more The techniques used for SPB control are based on recommended direct-control tactics. SPB control, biological and cost effectiveness. Furthermore, they to be most effective, should be a year-round activity refleci the reality ofSPB outbreaks and focus on the Major efforts should be made from late spring through achievable goal ofcontrollingspot growth. Four tech- fall to controlactivelyspreadinginfestations. Winterand niques or methods are used to control SPB spot growth. early spring treatment is also important to reduce the A briefdefinition ofeach follows: — potential for spot growth as well as new spot develop- 1. Cut and remove fellingand removal ofinfested ment later in the spring and summer. Although infesta- trees and abuffer ofadjacent, uninfested, green trees. tions are concentrated in fewer trees for longer periods (Figure 1) This technique reduces the number ofbee- of time during the colder months, the spots are harder tles available to attack new trees. to detect from the air because ofslower crown discol- — 2. Cut and leave fellingofinfested trees and a buffer oration. ofadjacent, uninfested, green, trees toward the center ofthe spot. This technique disrupts pheromone production and beetle attack- behavior. — 3. Cut and hand spray felling, limbingand buckinginfested trees into manageable lengths and hand sprayingwith Lindane or Dursban (Chlorpynfos). This technique destroysbeetle broodsbefore and duringemergence. — 4. Pileand bum felling, pilingand burning infested trees to destroybeetle broodsbefore RtCEIVEb they emerge. 2 DEC. 1 1994 DUCUMENTS , August). When cut and remove is used, onlyinfested trees should be cut; trees vacated by the SPB should remain standing. Uninfested trees within a 200-foot red-cockaded woodpeckerbuffershould notbe cut unless absolutelynecessaryto prevent the SPB from infesting cavity trees. CUT AND LEAVE General Forest Area Cut and leave involves felling infested trees and a bufferstrip of uninfested trees so that the crowns point toward the center ofthe spot. This treatment disruptsspot growth Fig. 1. Thebufferstnpshouldbeatleastthewidthofthetallesttreesinthespot,andshouldencom- and causes emergingadultbeetles to passtheactivehead. disperse into the surrounding forest. CUT AND REMOVE some financial return. However, It isusually recommended forspots with 100 infested trees orless. removal ofindividual spotsis not General Forest Area always practicalbecause ofinaccessi- Cut and leave is practical, Cut and remove is the prompt bility insufficientvolume, poorlum- relativelyinexpensive, and requires removal ofinfested trees. Removal ber orpulpwood markets, and a minimum oflabor, equipment, ofinfested trees and an adequate environmental considerations. In and training. The procedure canbe buffer strip preventsspots from addition, cut and remove often takes applied soon afterspots are spreading. The inclusion ofa buffer longerto implement than alternative detected. Freshly-attacked trees are ensures the removal offreshly- tactics. Despite these limitations, cut sometimes difficult to detect during attacked pines that were overlooked and remove, when properlyand the early stages ofattack. Therefore, orbecame infested after the spot promptlyapplied, remains the most the majordisadvantage is that a was first evaluated and marked. SPB practicalandeconomical control tac- buffer strip ofgreen, uninfested infested trees mustbe promptly tic for treatingmost large, rapidly- trees must be felled aroundeach removed to achieve maximum effec- growinginfestations. spot to assure that freshly-attacked tiveness: stoppingadditional spot trees are included in the treatment. spread. Because both the beetles In the general forest area, many and theirassociated pheromone Near Red-Cockaded Woodpecker landowners, are reluctant to source are removed from the site, Colony Sites sacrifice this bufferifthe trees cannotbe salvaged. the potential forspot spread is mini- Cut and remove can be Expandingspots involvingmore mized. disruptive to the red-cockaded Managers and owners usually woodpecker and should not be than 100 active trees are more prefercut and remove overthe other used duringthe red-cockaded difficult to stop with cut and leave. Breakouts are more likely to occur control options because infested woodpeckerbreedingseason (from treesare removed from the forest March 1 until the younghave forspots exceeding 100 active trees. and used, givingthe landowner fledged, approximatelyJuly- Nevertheless, cut and leave remainsuseful mainly because of son. After the breedingseason and will be limited because ofhigh — anotherbeneficial effect when a duringthe winter months the more costs, the need to fell andsprayall bufferstrip is included, it usually effective cut-and-remove method surfaces ofinfested trees, safety stops the expansion ofa spot. The canbe used. Trees vacatedby the precautions, and toxicityto non-tar- biological rationale forspot SPB will not be cut. Uninfested trees get organisms. disruptionby cut and leave isbased within a 200-foot red cockaded on the way individual spots expand woodpeckercolonybufferzone will dunngthe summer. Continuous not be cut unless absolutelyneces- Near Red-Cockaded Woodpecker spot growth requires at least three sary to prevent the SPB from infest- Colony Sites factors: emergingbeetles, nearby ing cavity trees. This method canbe used when pine trees, and a source of alternative methods are outside secondaryattractants. Felling the theireffective period (cut and leave most recently attacked trees CUT AND HAND SPRAY duringMarch and April) ornot eliminates the attractant source. The General Forest Area feasible, orwhen a biological felled bufferstrip eliminates nearby Cut and hand spray is the felling, evaluation determines that foraging unattacked pines, and beetles limbingand bucking ofinfested habitat loss due to controlmust be emerging from the infested trees trees into manageable lengths and minimized. Inno case will any tend to disperse in the absence of hand spraying with an insecticide. standingtreesbe sprayed. attractants. Insecticides may be used to control The fate ofbeetles that are not the SPB in individual trees orsmall killed or removed mechanically has groups oftrees. Registered PILE AND BURN been partially explained by SPB insecticides, Lindane and Dursban General Forest Area population dynamics research. This (Chlorpyrifos), are available for this Pile andburn refers to the felling, research has determined that long- purpose. Although chemical control piling, andburningofinfested trees. range beetle dispersal normally is costly and raisessome environ- This technique is one ofthe oldest occurswhen temperature— mental concerns, it maybe the best SPB control methods, and also is conditions are favorable from alternative in urban forests, high- one ofthe most effective when Novemberthrough March. Very value recreational areas and, to a properly done. However, because of little dispersal occurs dunngthe limited degree, in commercial high costs andenvironmental warmermonthsbecause ofthe forestswhen othermethods cannot constraints, the practice hasbeen weakened physiological condition be used. used sparinglyinrecentyears. The — ofthe beetles the stored fat from Because ofhigh costs and barkmust be completelyburned to which the beetles draw energy for environmental concerns, no large- achieve control. Vacated treesneed flight is lowest during this period. scale chemical barkbeetle control notbe cut, piled, and burned. For projects are likely tobe undertaken practical reasons, both infested and Near Red-Cockaded in the South. Nevertheless, a need vacated treesare usually piled and Woodpecker Sites remains fora fast-acting, effective burned to clear the site for Cut and leave is the preferred tactic to reduce SPB concentrations. regeneration. Because burningcan technique forcontrollingspots near To date, only insecticide sprays can cause wildfires, this technique red-cockadedwoodpeckercolony assure this level ofprotection. In should be restricted to periods of sites duringthe birds' breeding commercial forests, insecticides are low fire danger. Also, federaland season. The effectiveness ofthis useful for treatingsmall spots dur- state airpollution lawsmustbe method is greatest from May to ingthe winter, spotsinaccessible to followed. October, which generally coincides heavyequipment, and orbreakouts. The biological rationale forpile with the red-cockadedbreedingsea- The use ofinsecticides in forests and burn is comparable to that for cut and remove and cut and hand Near Red-Cockaded Woodpecker southern pine beetles is the check- — spray the beetles are destroyed if Colony Sites ered beetle. (Figure 2) Regardless of the infested bark is completely This method will notbe used in the control technique, older killed burned. This practice hasbeen ornearactive red-cockaded wood- trees should be left standing where largely abandoned, however, pecker colonies. feasible toprotectasmanycheckered because ofthe laborand logistical beetles as possible. These older kills usually harbor numerous checkered problems involved. In most cases, BIOLOGICAL CONTROL beetles, andtheyalsoprovidevarious heavyequipment must be used to woodpeckerswithnestingsites. pile the trees. Inwet areas, burning Several species of parasitic and felled treesbecomes extremely predacious insects feed on southern difficult. In dryareas, the procedure pinebeetles. Theirabilityto keep the southern pine beetle under control increases the chances ofwildfire, and burningmustbe restricted to depends on many factors. The insect dayswhen fire dangeris low. most famous for its ability to devour Fig. 2.Anadultcheckered beetle feedingonasouthern pinebeetle Checkeredbeetlesrequirealongerdevelopmentperiodthansouthernpinebeetlesand this reason that older kill treesbe left when feasible