Southern Pine Beetle (SPB)

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2 Southern Pine Beetle (SPB) SPB is the most destructive pest of pine forests in the South. SPB outbreaks are cyclic, with peaks usually every 6-9 years. Multiple-tree infestations (spots) may expand rapidly if not controlled, killing even healthy pines. Prompt direct control can reduce economic losses but only prevention activities will reduce the frequency and duration of SPB outbreaks.

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4 SPB Infestations Detected in East Texas Infestations Detected (Thousands) Year

5 December SPB Spots by Month on the NFT, January February March April May June July August Sepember October November SPB Infestations

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9 Indian Mounds Wilderness in Texas July 1992 Small SPB spots

10 Indian Mounds Wilderness in Texas February 1993 Many uncontrolled SPB spots converge into an expanding infestation 11-year old pine plantation

11 Indian Mounds Wilderness in Texas June year old pine plantation

12 Indian Mounds Wilderness in Texas August year old pine plantation 7,500 acres killed by SPB U

13 SPB Prediction System For detailed instructions on how to monitor SPB and clerid predators with pheromone traps as a means to predict SPB infestation trends, see the tutorial entitled How to Predict Southern Pine Beetle Infestation Trends with Pheromone Traps on the Texas Forest Service web page at: and_diseases/insects/southern_pine_beetle/index.html SPB adult Clerid adult (major predator of SPB)

14 SPB Prediction System Prediction accuracy = 70-85%. Developed in 1986 and administered annually TFS. Uses pheromone traps deployed in spring to predict SPB infestatio trends and levels. Utilized by state and fede agencies in 13 southe states.

15 Direct Control Methods for SPB Cut-and-remove (salvage) Cut-and-leave Chemical control (seldom used) Pile-and-burn (seldom used) Verbenone (SPB inhibitor) No control (small or inactive spots and those on wilderness) See USDA Agriculture Handbook No. 575 Direct Control Methods for the Southern Pine Beetle (also available in Spanish).

16 Buffer Strips for SPB Control (used with cut-and-remove and cut-and-leave treatments)

17 SPB Spot Controlled by Cut-and- Remove Prompt direct control can reduce losses by 85% or more.

18 Turkey Hill Wilderness

19 Prevention is the preferred long-term solution for minimizing the severity and duration of SPB outbreaks in managed forests.

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21 Eastern Forest Entomology Ips engraver beetles

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24 Eastern Forest Entomology Black turpentine beetle

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31 Texas Leaf-Cutting Ant (Town Ant or Cut Ant) (Atta texana)

32 Texas Leaf-cutting Ant Native to eastern Texas and west central Louisiana Prefers deep, sandy soil Collects green vegetation and builds towns Strips needles and buds from pine seedlings during winter months The ants don t eat the leaves Causes the seedling to die

33 Range of Texas Leaf-Cutting Ant

34 Texas Leaf-Cutting Ants Reproductives Workers Workers

35 Leaf-cutting ant workers literally destroying a young pine seedling

36 Leaf-cutting ant workers harvesting oak leaves

37 Typical Town Ant Mounds Notice the course, granular soil particles associated with fresh excavation.

38 Central nest area of Texas leafcutting ant colony. Notice the high density of mounds.

39 BARK LICE, TREE CATTLE, OR PSOCIDS They don t do any damage to a tree, but really grab your attention.

40 The strange webbing, that may appear on a tree overnight, is very striking and causes concern about tree health. The tree is not harmed and no control is needed.

41 TENT CATERPILLARS Eastern tent caterpillar Eastern tent caterpillar Forest tent caterpillar Forest tent caterpillars (foot prints along back) don t make tents

42 Both the forest and eastern tent caterpillars overwinter as eggs encircling twigs of host plants. The larvae hatch in the early spring as the leaves are unfolding from their buds. There is one generation per year. Eggs that have hatched Eggs that have not hatched

43 FOREST TENT CATERPILLAR Forest tent caterpillar defoliation occurred in mixed hardwood forests on the lower Trinity, Neches, and Sabine river bottoms the spring of 2002, covering over 125,000 acres. This insect is present each spring, but tends to be very localized. These caterpillars do not cause a serious problem since the trees refoliate by early summer and only suffer minor growth loss.

44 Forest Tent Caterpillar Larvae of the forest tent caterpillar are easily identified by the footprint or keyhole pattern along their backs. This caterpillar does NOT make a distinct tent.

45 EASTERN TENT CATERPILLAR This caterpillar is especially fond of wild cherry, plum, and other trees in the genus Prunus. Distinct tents can be found in the early spring at branch junctions.

46 The colorful larvae are easily identified by the solid light-colored line down the center of their backs. EASTERN TENT CATERPILLAR

47 FALL WEBWORM

48 Fall Webworm Don t confuse the fall webworm with the tent caterpillar. Tent caterpillars ONLY occur in the early spring. Fall webworms occur throughout the summer months. They are particularly fond of pecan and sweetgum.

49 Orangestriped Oak Worm Anisota senatoria A fall defoliator of oak trees in eastern Texas

50 Orangestriped Oak Worm Anisota senatoria

51 Oak Leaf Roller Archips semiferana Silk threads on which larvae have descended.

52 Oak Leaf Roller Archips semiferana

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