Ips Bark Beetles in the Southeastern U.S

Home , Bark beetle, Dendroctonus, Dendroctonus terebrans, Ips (beetle), Ips calligraphus, Ips grandicollis

SREF-FH-002 June 2016

Ips Bark Beetles in the Southeastern U.S.

AUTHORED BY: DAVID R. COYLE, A. BRADY SELF, JAMES D. FLOYD, Four species of Ips bark beetles (also AND JOHN J. RIGGINS commonly known as Ips engraver beetles or Ips beetles) occur throughout pure and mixed pine forests in the southeastern U.S.: the six-spined ips (Ips calligraphus), the pine engraver (Ips pini), the eastern five-spined ips Ips( grandicollis), and the small southern pine engraver (Ips avulsus). Ips beetles appear similar to other bark beetles in this region, including the southern pine beetle (SPB), black turpentine beetle, and red turpentine beetle (Table 1, Fig. 1). These beetles occur throughout the entire southeastern U.S., with the exception of the pine engraver Figure 1. Commonly-encountered bark beetles in the southeastern U.S., scaled to size with a dime. Ips bark beetles are distinguished by spines/bumps on their posterior, while Dendrocto- and red turpentine beetle, which are nus species have smooth posteriors. found only in the Appalachian region.

Table 1. Common bark beetles in the southeastern U.S.

Common name Scientific name Average size Host tissue utilized Distribution

Small southern pine engraver Ips avulsus 2.1-2.8 mm Crowns, small/medium Entire southeastern U.S. (Eichhoff) (1/16-1/8“) branches, small diameter slash, upper bole

Eastern five-spined Ips Ips grandicollis 2.9-4.6 mm Middle/upper bole, large Entire southeastern U.S. (Eichhoff) (1/8-3/16”) limbs, recently-felled trees and slash

Six-spined Ips Ips calligraphus 3.8-5.9 mm Lower/middle bole, large Entire southeastern U.S. (Germar) (1/8-1/4”) limbs, slash Pine engraver Ips pini 3.3-4.3 mm Sapling and pole-sized Appalachian Mountain (Say) (1/8-3/16”) trees, slash, crowns region, south to the northern part of GA Southern pine beetle Dendroctonus frontalis 2.0-3.2 mm Main bole Entire southeastern U.S. (Zimmermann) (1/16-1/8“)

Black turpentine beetle Dendroctonus terebrans 5.0-7.5 mm Lower bole, occasionally Entire southeastern U.S. (Olivier) (3/16-5/16”) structural roots

Red turpentine beetle Dendroctonus valens 5.3-8.3 mm Lower bole, occasionally Appalachian Mountain (LeConte) (3/16-5/16”) structural roots region, south to the northern part of GA

www.southernforesthealth. 1 Table 2. Native pine species in the southeastern U.S. and use by Ips bark beetles as hosts. of a tree (Table 1), although there is a b (Table modified from Connor and Wilkinson 1983.) considerable overlap. Male Ips bore entrance tunnels through the outer bark and excavate chambers in the Pine Species Ips Species inner bark (cambium and phloem Common name Scientific name calligraphus grandicollis pini avulsus tissue). Males produce chemicals (pheromones) that are released into Eastern white pine P. strobus L. X X X X the air and attract females to the newly-made chamber1. Multiple Loblolly pine P. taeda L. X X X females (up to 7) enter the chamber, Longleaf pine P. palustris Mill. X X X mate, and lay eggs along galleries in the phloem. Female egg galleries are Pitch pine P. rigida Mill. X X X straight and vertically-oriented on the Pond pine P. serotina Michx. X X X stem, and often form an “I”, “H”, or Sand pine P. clausa (Chapm. ex Engelm.) Sarg. X X X “Y” shape (Fig. 2). Individual galleries range from 4 to 7 inches in length Shortleaf pine P. echinata Mill. X X X with eggs being laid along either Figure 4. Ips bark beetle colonization on individual tree branches (identified by white arrows) side of the gallery. After hatching, on otherwise healthy loblolly pine trees in Morgan (A) and Putnam (B) Co., GA. This is known as Slash pine P. elliottii Engelm. X X X the white, legless larvae create their branch “flagging”. Spruce pine P. glabra Walt. X own galleries (perpendicular to the parent galleries) as they feed in the through the outer bark to repeat the under warm weather conditions, but Table Mountain pine P. pungens Lamb. X X inner bark. Larvae pupate at the life cycle. Exit holes are about 1/16 develop slowly when temperatures end of the feeding galleries, and inch in diameter and perfectly round. drop below 59o F. 2. Depending Virginia pine P. virginiana Mill. X X X X the new adults mature and bore out Ips populations can increase rapidly on weather conditions and host availability, Ips beetles can produce between six and ten generations become black as they mature. The colonize other conifers such as fir, per year in warm climates and may Identification beetles are small, ranging between spruce, and hemlock. complete development in less than <1/16th inch and nearly 1/4th inch three weeks4. Ips beetles can be distinguished from in length (Table 1, Fig. 1). Ips bark other bark beetles by the presence of beetles can also be distinguished Ips Bark Beetle Bi- “spines” along a depression located from other bark beetles by the size Symptoms and at the rear of the abdomen (Fig. and pattern of the galleries they leave 2). The size of the beetle as well as behind under the bark of colonized Ips beetles usually colonize stressed Signs of an Ips Bark number of spines helps to identify trees (Fig. 2). Ips beetles can colonize trees, logging slash, or injured species. Freshly emerged adult Ips any pine species within their range branches (e.g. Fig. 3). Ips species Symptoms of a bark beetle infestation bark beetles are light brown and (Table 2). Occasionally, they may tend to attack predictable sections are the tree’s responses to being colonized. Discolored crowns, dying and dead branches, sloughing bark, a b c d and dead trees are all symptoms of an Ips infestation. Pitch tubes, galleries, emergence holes, boring dust, frass (beetle excrement and sawdust), and Ips beetles or larvae themselves are all direct signs of bark beetles. Symptoms are easier to recognize than signs and are usually the first thing observed when trees are colonized. But, through closer inspection, the signs allow you to identify the type of bark beetle present.

Figure 2. The four species of Ips bark beetles in the southeastern U.S. and their associated gallery patterns: I. avulsus (A), I. grandicollis (B), I. pini Figure 3. Broken limb on shortleaf pine in Clarke Co., GA. Limbs such as these are commonly (C), and I. calligraphus (D). colonized by Ips bark beetles. Ips avulsus often colonize individual

www.southernforesthealth. 2 www.southernforesthealth.net/ 3 Ips a b can complete their development in Table 3. A comparison of bark beetle, southern pine beetle (SPB), and turpentine beetle symptoms and signs. this tree tissue. In otherwise healthy trees, Ips rarely move beyond the Symptom or sign Ips bark beetles SPB Turpentine beetles damaged branches. Ips beetles also Ips avulsus attacks appear as fading on Entire crown fades uniformly Most infestations are insignificant— help selectively remove stressed, old, Tree damage pattern over time individual branches; Ips calligraphus or from yellow to red to brown no crown damage pattern. or otherwise weakened or injured Ips grandicollis attacks on the main stem With heavy infestation, entire crown trees as part of natural succession. lead to crown turning yellow, red, and fades uniformly from yellow to red to Normally referred to as “secondary eventually brown brown. invaders,” Ips beetles attack trees that are affected by some other Gallery shape I, H, or Y-shaped, usually vertical S-shaped or winding side to ?-shaped, upside-down J-shape, or condition; a stressed or damaged side pie-shaped c d tree produces chemical signals that Pitch tubes Usually not present. When they are Located in bark crevices, any- Lower 10’ of tree, large (~1” indicate to Ips beetles that the tree present, located on bark plates – the flat where on tree, small (<1/2” diameter) is vulnerable. A large cluster of tree part of the bark, anywhere on tree (but diameter) mortality from an Ips infestation is see Table 1), small (<1/2” diameter) unusual. Mortality is usually limited to only one or a few trees in a specific location (Fig. 6a), but a checkerboard Adult galleries Usually not packed with frass Usually packed with frass Usually not packed with frass pattern of fading and healthy trees may evolve as Ips moves throughout Figure 5. A comparison of different pitch tubes/entrance holes made by bark beetles in the the stand infesting the weakest trees9 Landscape damage One or few trees, checkerboard pattern, Defined spots One or few trees, checkerboard southeastern U.S. Southern pine beetle entrance hole and pitch tube (A), Ips bark beetle (Fig. 6b). In general, widespread pattern spots only during droughts or other pattern, rarely see significant entrance hole and pitch tube (B), black turpentine beetle entrance hole with pitch tube (C), and drought is one of the main factors large-scale tree stress event mortality. Tree usually has signs of Ips bark beetle exit hole (D). that can cause high Ips densities and some other physical damage significant mortality that occurs as a small branches on a tree, killing “spot” rather than a checkerboard only the infested branches. When Infestations in pattern. For example, in northwestern Ips beetles (i.e. colonizing large made disturbances. For instance, individual branches are infested and Mississippi during fall 2015, an Ips areas) is generally associated with Infestations in large numbers of Ips beetles may needles begin to fade, the resulting Standing Trees beetle infestation occurred that big disturbances on the landscape. accumulate in areas where lightning damage is called branch “flagging” covered nearly an acre in size and In this case, the region had been in Damaged Trees storms, ice storms, tornadoes, (Fig. 4). Other Ips species usually Ips beetles infest branches that are killed ~60 trees (Fig. 7a). Beetle a very heavy drought all through the wildfires, hurricanes, and droughts infest the bole (or main trunk) and weakened by certain conditions populations were so high on some summer and fall months (Fig. 7c), Ips beetles are endemic in most result in large numbers of damaged larger branches, resulting in tree (e.g., damage by storms or lower trees that frass and sawdust were which likely contributed to the stand’s pine stands of the Southeast and will or weakened pines, which are suitable mortality. It is not uncommon to see crown branches that are being easily visible on ground vegetation increased susceptibility to Ips beetles. take advantage of natural or man- for colonization by bark beetles2,10. multiple Ips species attacking a tree “self-pruned” by the tree) and they (Fig. 7b). This type of behavior by resulting in individual larger branches For example, hurricanes are known to turning yellow (called “fading”) leave excessive slash and damaged a b first, followed by the remainder of a b trees in their wake, which are often the crown fading, then turning red heavily colonized by Ips beetles 5,8,12 (recently dead) and finally brown within a year . Ips populations (completely dead). Pitch tubes may also increase following forestry caused by Ips beetles generally occur activities such as prescribed burns on the flat part of bark plates (Fig. 5). that are too intense, as well as When Ips beetles colonize a drought clearcutting or thinning operations stressed tree, pitch tubes may be that wound trees and leave large c 2,6 absent and the boring dust and frass amounts of slash for breeding sites . may be the only external sign of attack. Additionally, small emergence Activities such as thinning operations holes can be observed along the can also result in large amounts of bole of the tree after an entire life slash, and Ips beetles often colonize cycle is completed. In slash material the logging slash or trees wounded colonized by Ips, boring dust and during harvest (though this generally frass will still be present, but a pitch happens only if slash is piled next to Figure 7. Ips bark beetle “spot” (A), beetle frass and sawdust on ground foliage (B), and U.S. a wounded tree, or a wounded tree tube probably won’t due to the lack Figure 6. Dead and fading tree killed in an Ips bark beetle infestation (A) and aerial view of Ips- Drought Monitor report from October 20, 2015, showing intense drought throughout much of of resin. killed trees on the landscape (B). western Mississippi (C). is otherwise weakened by drought).

www.southernforesthealth. 4 www.southernforesthealth. 5 Fresh slash material from harvest damage or stress to infested trees in seemingly healthy trees. Abiotic licensed pesticide applicators in protection against soil compaction Ips bark beetle infestation. In urban operations can provide breeding the first place is very important for stresses include soil conditions accordance with label directions. and rutting from logging equipment. areas, this can include avoiding material to sustain all four Ips species managing to minimize or eliminate including compaction, improper use Much more information on pesticide If slash redistribution is not possible or minimizing soil compaction, in the southeastern U.S.3,7. Minimizing that stressor and ultimately the long- of pesticides, drought or excessive application is available from the or desired, residual slash piles can especially in construction areas. soil compaction and mechanical term impacts of Ips. rainfall, weather events, root or trunk USDA Forest Service: be burned or chipped. However, if Replacing turfgrass with mulch within wounds on residual trees following a damage, poor or excessive drainage, www.fs.fed.us/foresthealth/pesticide, burning is employed, take care to the drip zone or extent of the crown harvest can help reduce subsequent Causal agents can be biotic (living) poor nutrient management, grade or from your state’s cooperative ensure residual trees are not damaged. provides a more natural environment Ips beetle problems. or abiotic (non-living). Biotic agents changes and excessive competition extension service. Please consult a At the very least, try to keep slash piles for roots to thrive. Supplemental include primary insects (including or overstocked stands (too many professional prior to any pesticide away from remaining trees. watering of pine trees growing in repeated attacks by defoliators or trees competing for limited resources) usage. residential areas during periods of Characteristics of sapsucking insects) or diseases (like to name a few. Tree age may also be Storm-damaged trees are very drought may be useful in preventing leaf blights and root rots) that attack a contributing factor. STAND MANAGEMENT PRACTICES susceptible to Ips bark beetle damage. Ips bark beetle attacks, as this could Promptly removing these trees not reduce overall tree stress, but there Bark Beetle Infesta- Sound management practices are only reduces the chance of an Ips bark have been no studies conducted to key to the stand-level prevention of beetle infestation, but it also preserves test its effectiveness. Consult with tions in the South- Management Practices to Minimize Ips Ips bark beetle infestations. Stand value by getting the wood to a buyer a local arborist or urban tree health thinning should be scheduled and before other insects or fungi can professional if you have questions Ips bark beetles, SPB, and turpentine Bark conducted so that trees remain colonize the damaged trees. about protecting a high-value tree beetles create many similar symptoms vigorous. Thinning is useful in from potential Ips bark beetle and signs on colonized trees (Table preventing bark beetle attacks, but Sometimes, Ips bark beetles may damage. Several techniques should lessen both frequency and severity of damage from doing so too early in the rotation 3), and damage from these beetles is Ips bark beetles. The best way to decrease risk of Ips beetles and mitigate not impact enough trees to warrant easily confused. Correct identification can decrease the value of future mechanical harvesting or salvaging. damage if they occur is to promote tree and stand health through good sawtimber, while thinning too late of the bark beetle species responsible management. Prevention is the best strategy to limit Ips activity. Preventa- In these cases, letting Ips bark beetle decreases tree vigor and can actually for an attack is critical for prescribing tive management strategies include planting tree species appropriate to a infestations run their course may Summary increase the stand’s susceptibility proper management strategies to particular site, keeping woody and herbaceous competition under control, be the most economical option. to bark beetle infestations11. Pine However, if mortality is significant in lessen further damage to remaining and implementing prescribed burning when appropriate. Avoiding injuries to Four species of Ips bark beetles are trees are most susceptible to attack a stand, removal of affected trees or trees. Ips and turpentine beetles residual trees during a harvest (or other management activity) is also import- present in the southeastern U.S. and from Ips bark beetles during drought a partial stand harvest may be the are usually much less aggressive ant. Ultimately, preventative strategies limit the host suitability in a given area are commonly found in the same trees conditions, so thinning during these best course of action, taking care not than SPB, which is a primary killer of by creating conditions favorable to vigorous tree growth. as three somewhat similar-looking times should be avoided if possible. to damage nearby healthy residual healthy pine trees in the southeastern bark beetle species. Ips bark beetle Consultation with a professional trees. When mortality throughout U.S. Ips beetles are commonly found infestations are often misidentified as CHEMICAL TREATMENTS symptoms are obvious), the tree forester is recommended before the stand exceeds a critical threshold in the same stand and in the same SPB infestations, but differ in several cannot be saved by insecticides. making a pine thinning decision necessary to maintain full stocking tree as SPB. In these cases, SPB is Preventative treatments may be important ways. Proper identification Stand-level treatments are not cost (see Resources section at the end levels, a complete stand harvest may generally the insect dictating tree suitable for high-value trees, but of the species of bark beetle and effective for most nonindustrial of this document). sometimes be the most practical mortality, and most of the outward chemicals are generally not used conditions responsible for stand or private landowners. course of action. This can occur, for symptoms and signs would point to for Ips bark beetles over large tree stress will greatly influence the To help alleviate Ips bark beetle example, during severe and sustained SPB, but Ips beetles are often using areas. A few topical insecticides are recommended management activity or There is no way to predict if or problems after harvest, log deck drought periods even in well-thinned this host material, too. labeled for Ips bark beetles (e.g. control method. Unlike SPB, Ips may when Ips bark beetles will colonize placement and slash management stands. Where sufficient wood carbaryl and permethrin); however, infest slash left by harvesting activity a tree. In general, expect them in are important factors to consider. markets are not available, infested these chemicals must be applied or natural disturbances; consideration times of drought or after a storm Log decks should be kept away from trees may be cut down and left on- repeatedly, and the entire tree, should be given to proper handling Once Ips bark bee- has damaged trees. Any prevention remaining pine trees. All the machine site; however, care must be taken not including the upper portions of the of this potential resource for Ips bark treatments should be considered at activity associated with log decks can to damage adjacent healthy trees. crown, must be sprayed by a certified beetles during harvesting activities. tles are diagnosed, the first indication of an extended stress nearby trees by compacting soil Further, these felled trees should be applicator. Systemic insecticides (e.g. Ips bark beetle habitat is also created drought or after a particularly and damaging roots. Slash should be cut into short lengths to encourage emamectin benzoate, sold as Tree- damaging storm. Trees and forest from damaged trees and rutting/ As stated above, Ips bark beetles ® redistributed throughout the stand, quick drying and bark sloughing, äge ) have shown effectiveness in may suffer from internal and external compacting soils during harvest or are secondary invaders or threats: and this can be accomplished by reducing their usefulness for bark controlling bark beetles, but these damage caused by droughts and other construction activities. Thinning they only attack trees that have logging crews. As slash is run over by beetle habitat. require injection directly into the storms for several years, so trees is a preventive measure that will help equipment it gets broken down and been damaged or weakened by trunk of the tree. For high-value trees, should be monitored and possibly reduce future damage by both Ips exposed to light, wind and extreme some other causal agent. Therefore, insecticide use is recommended treated for extended periods after bark beetles and SPB. Implementing temperatures, all of which can lessen IPS BARK BEETLE MANAGEMENT diagnosing Ips beetles in a tree or only as a preventive measure to these events. proactive management practices is stand of trees is a good first step control Ips beetle damage before slash suitability for Ips bark beetle IN URBAN AREAS the best course of action to minimize toward diagnosing a larger problem. infestation occurs. Once bark beetles breeding and reproduction. Slash Remember - IT’S THE LAW - Any practice that reduces tree future damage from both SPB and Ips have colonized a tree (i.e., crown distribution may also provide some Determining what caused the Pesticides must be applied by stress will lessen the chance of an bark beetles.

www.southernforesthealth. 6 www.southernforesthealth. 7 This document was modified from Publication 2876, Ips: The Other Pine Bark Beetles, Extension Service of Mississippi State University, cooperating with U.S. Department of Agriculture. Resources

For the location and phone numbers of state agencies in Oklahoma Cooperative Extension Service: AUTHORS: the southeastern U.S. providing forestry assistance and http://www.oces.okstate.edu/ information, see the following websites: Clemson Cooperative Extension (South Carolina): David R. Coyle, Forest Health Extension Associate, Southern Regional http://www.clemson.edu/extension/ Extension Forestry and D.B. Warnell School of Forestry and Natural Resources, Alabama Forestry Commission: http://www.forestry.alabama.gov/ University of Georgia University of Tennessee Extension: https://extension.tennessee.edu/ Arkansas Forestry Commission: A. Brady Self, Assistant Extension Professor, Department of Forestry, Mississippi http://forestry.arkansas.gov/Pages/default.aspx Texas A&M AgriLife Extension: http://agrilifeextension.tamu.edu/ State University Florida Forest Service: http://www.floridaforestservice.com/ Virginia Cooperative Extension: http://www.ext.vt.edu/ James D. Floyd, Forestry Instructor, Holmes Community College Georgia Forestry Commission: http://www.gatrees.org/ John J. Riggins, Assistant Professor, Department of Biochemistry, Molecular To locate a consulting forester: Biology, Entomology, and Plant Pathology, Mississippi State University Kentucky Division of Forestry: http://forestry.ky.gov/Pages/default.aspx Association of Consulting Foresters: http://www.acf-foresters.org/acfweb. Louisiana Department of Agriculture and Forestry: SREF-FH-002 | www.sref.info http://www.ldaf.state.la.us/ Click on “Find a Forester”, then select your state in the A Regional Peer Reviewed Technology Bulletin published by “People Search – Public” search page. http://www.mfc.ms.gov/ Southern Regional Extension Forestry, Mississippi Forestry Commission: William G. Hubbard, Regional Forester, North Carolina Forest Service: http://www.ncforestservice.gov/ For more information on how to select a consulting ASRED/CES- Southern Region. forester, go to: Oklahoma Forestry Services: http://www.forestry.ok.gov/ Southern Regional Extension Forestry (SREF) is a diverse team of trained natural resource educators, IT specialists, graphic designers, communi- cations and marketing experts, and media and content producers. SREF works closely with the Southern Land Grant University System, US Forest South Carolina Forestry Commission: http://msucares.com/pubs/publications/p2718.pdf Service, and state forestry agencies to develop content, tools and support for the forestry and natural resource community. To find out more http://www.state.sc.us/forest/ http://texashelp.tamu.edu/011-disaster-by-stage/pdfs/recovery/ER- about SREF programs please visit www.sref.info. 038-Selecting-a-Consulting-Forester.pdf Tennessee Division of Forestry: https://www.tn.gov/agriculture/section/forests http://www.uaex.edu/environment-nature/forestry/FSA-5019.pdf ACKNOWLEDGEMENTS: Texas A&M Forest Service: http://texasforestservice.tamu.edu/ We thank S. Clarke, C. Asaro, F. Stephen, C. Barton, and R. Trickel for helpful comments on earlier versions of this document. Virginia Department of Forestry: http://www.dof.virginia.gov/ Photo Credits For the location and phone numbers of University Figure 1: David R. Coyle, Southern Regional Extension Forestry References Extension personnel in the southeastern U.S. providing and University of Georgia, and Joseph V. McHugh, forestry assistance and information, see the following University of Georgia websites: 1Birgersson, G., M.J. Dalusky, K.E. Espelie, and C.W. Berisford. 2012. 7Nebeker, T. E. 2003. Integrated forest pest management. In: Integrated Figure 2: A: insect, Michael Ferro, Louisiana State Arthropod Museum; damage, Ronald Billings, Texas A&M Forest Pheromone production, attraction, and interspecific inhibition among four Pest Management: Current and Future Strategies. Council for Agriculture Alabama Cooperative Extension System: http://www.aces.edu/main/ Service, Bugwood.org; B: insect, Michael Ferro, species of Ips bark beetles in the southeastern USA. Psyche 2012, Article Science and Technology (CAST). Task Force Report 140. pp. 11-116. Louisiana State Arthropod Museum; damage, Jeffrey ID 532652, 14 p. M. Eickwort, Florida DACS, Bugwood.org; C: insect, 8Nebeker, T. E. 2009. Forest Health. Chapter 13 In: Wallace, M. J. and A. J. University of Arkansas Cooperative Extension Service: http://www.uaex.edu/ Natasha Wright, Cook’s Pest Control, Bugwood.org; 2Connor, M. D., and R. C. Wilkinson. 1983. Ips bark beetles in the south: Londo (Eds). Managing the Family Forest in Mississippi, Publication 2470. damage, Texas A&M Forest Service, Bugwood.org; D: insect, Michael Ferro, Louisiana State Arthropod Forest Insect and Disease Leaflet 129, U.S. Department of Agriculture 98 p. University of Florida’s Institute of Food and Agricultural Museum; damage, Tim Tigner, Virginia Department of Forest Service. Available online at http://www.barkbeetles.org/ips/ipsfidl. Sciences (UF/IFAS): 9 Forestry, Bugwood.org. htm. Accessed 18 July 2008. Stone, D., T. E. Nebeker, and A. J. Londo. 2007. Identifying and http://solutionsforyourlife.ufl.edu/ Controlling the Southern Pine Bark Beetles. Mississippi Forestry David R. Coyle, Southern Regional Extension Forestry 3 http://extension.uga.edu/ Figure 3: Drooz, A.T., 1985. Insects of Eastern Forests. Misc. Publication 1426. U.S. Commission and Mississippi State Extension Service, Publication 2448. University of Georgia Extension: and University of Georgia Department of Agriculture, Forest Service, Washington, DC, 608 p. 10 Kentucky Cooperative Extension Service: Thatcher, R. C., J. L. Searcy, J. E. Coster, and G. D. Hertel (eds.). 1980. The Figure 4: David R. Coyle, Southern Regional Extension Forestry 4 https://extension.ca.uky.edu/ Eickwort, M. J., E. A. Mayfield III, and L. J. Foltz. 2006. Ips Engraver Beetles southern pine beetle. US Forest Service, Technical Bulletin 1631. 266 p. and University of Georgia (Coleoptera: Curculionidae: Scolytinae). Florida Dept. Agriculture & Con. Louisiana Cooperative Extension Service: Serv. Division of Plant Industry, Entomology Circular No. 417. 11Traugott, T. A., and S. Dicke. 2006. Are My Pine Trees Ready To Thin? http://www.lsuagcenter.com/ Figure 5: James McGraw, North Carolina State University, Mississippi State Extension Service, Publication 2260. Bugwood.org. 5Hook, D.D., M.A. Buford, ad T.M. Williams. 1991. Impact of Hurricane Mississippi State University Extension Service: Hugo on the South Carolina Coastal Plain forest. J. Coastal Res. 8: 291-300. 12Wilkinson, R.C., R.W. Britt, E.A. Spence, and S.M. Seiber. 1978. Hurricane- http://extension.msstate.edu/ Figure 6: Ronald F. Billings, Texas A&M Forest Service, Bugwood.org Tornado Damage, Mortality, and Insect Infestations of Slash Pine. South. J. North Carolina Cooperative Extension: 6Mayfield, A. E., III, J. Nowak, and G. C. Moses. 2006. Southern Pine Beetle Appl. For. 2: 132-134. https://www.ces.ncsu.edu/ Figure 7: A. Brady Self, Mississippi State University; map created Prevention in Florida: Assessing landowner Awareness, Attitudes, and by Brad Rippey, USDA, available online at Actions. J. For. 104: 241-247. http://droughtmonitor.unl.edu.