Southern pine beetle: biology, prevention, & restoration [Feb. 2013]

Longleaf Pine Establishment in speciled areas of the State

Longleaf pine is the most resistant pine to southern pine beetle attack (Figure 11). Landowners should consider planting longleaf pine instead of loblolly within it's natural range (Figure 12).

For more detailed information concerning the Southern Pine Beetle Prevention and Restoration Program, you may contact the nearest GFC District Office:

COOSA DISTRICT - 1

*ainesville 2fce

Rome 2fce

3005 Atlanta Highway 3086 Martha Berry Hwy NE

Gainesville, GA 30507

Rome, GA 30165

770-531-6043/6048

706-295-6021/6022

Figure 11- Photo by James Johnson, GFC
State of Georgia Historic Longleaf Pine Range
Legend
County Boundary Historic Longleaf Pine Range

FLINT DISTRICT - 2

&amilla ofce

Americus ofce

3561 Hwy 112

243 US Hwy 19 North

Camilla, GA 31730

Americus, GA 31719

229-522-3580/3581

229-931-2436/2437

OCONEE DISTRICT - 3

Milledgeville ofce

:ashington ofce

119 Hwy 49

1465 Tignall Rd

Milledgeville, GA 31061 Washington, GA 30673

478-445-5164/5548

706-678-2015

Figure 12- Native longleaf range in Georgia

Hardwood planting (statewide)

Pine stands that have been killed by southern pine beetles can be converted to desirable hardwood plantings. Mast producing species will improve wildlife habitat for many species of game and nongame animals.

CHATTAHOOCHEE DISTRICT - 4 Newnan 2fce 187 Corinth Road
Newnan, GA 30263 770-254-7218

SATILLA DISTRICT - 5
Waycross 2fce 5003 Jacksonville Hwy. Waycross, GA 31503
912-287-4915

OGEECHEE DISTRICT - 6

Mc5ae ofce

Americus ofce

Route 1 Box 67

243 US Hwy 19 North

Helena, GA 31037

Americus GA 31719

229-868-3385

229-931-2436/2437

Funds for this publication are provided by the USDA Forest Service. Rev. 02/13

Southern Pine Beetle
Biology, Pevention, & Restoration

Introduction
Figure 1 - Photo by David Almquist, University of FL

The Southern Pine Beetle (SPB) Dendroctonus frontalis, is not much bigger than an eye gnat (Figure 1). It attacks and kills all species of southern yellow pines in
Georgia including white pine. Trees are killed when beetles construct winding S-shaped egg galleries underneath the bark (Figure 2). These galleries effectively girdle the tree and destroy the conductive tissues that transport food throughout the tree. Furthermore, the beetles carry bluestaining fungi on their bodies that clog the water conductive tissues (wood) that transport water within the tree. Signs of attack on the outside of the tree are pitch tubes and boring dust (frass) caused by beetles entering the tree (Figures 3 & 4).

Additional signs are egg pits

created by a secondary beetle

Figure 2 - Photo by

called the southern pine

Ronald Billings, sawyer (Figure 5). Needles turn pale green

Texas Forest Service to yellow to red then brown (Figure 6). Trees

under drought stress may not produce

pitch tubes when attacked by southern

Figure 3 - Photo by Tim Tigner, Figure 4 - Photo by Erich G. Vallery,

VA Dept of Forestry

USDA Forest Service

pine beetles and that is why the other signs are important in identifying infested trees.

Figure 5 - Photo by Lacy L. Hyche, Auburn University

Southern pine beetles have killed over $254 million worth of pine trees in Georgia since 1972. That's an average annual loss of over 7 million. If the trees were placed end-to-end, they would reach to the moon eight times. No other insect comes close to causing this much economic damage to Georgia's pine forests.

Based on 32

years of aerial

survey data in

Georgia, SPB

outbreaks

are cyclic

and often

correspond to

weather events

of drought

Figure 6 - Photo by Gerald J. Lenhard,

or flooding depending on the location within Georgia.

LA State University The data further suggests that Piedmont

populations increase to epidemic levels

every 6-10 years, while those in the

Mountain region occur every 12 years,

with both being inuenced by drought.

Outbreaks occurring in the Coastal Plain

are more sporadic and can be triggered by

ooding or drought. Outbreaks may persist

for 1-3 years.

Pines are most susceptible when they are stressed by drought, flooding, storm damage, or by stand conditions such as over crowding, old age, or root disease. Lightning struck trees are particularly vulnerable to attack as are trees damaged

Figure 7 - Photo by Erich G. Vallery, USDA Forest Service

by road building or logging activities (Figure 7). All of the above factors help sustain beetles when their numbers are low. But during epidemic years when beetle numbers are sky-rocketing, even the healthiest of trees/stands are killed. Therefore, foresters need to conduct practices that promote tree vigor while beetle populations are low. This is best achieved by thinning overcrowded pine stands to reduce competition between trees and by selectively removing those that are diseased. Certain pathogens that lead to diseases (such as pitch canker, littleleaf disease, and other root diseases) can weaken pines and create stands that are especially vulnerable to SPB attack and damage (Figure 8).

Figure 8 - Photo by Terry Price, retired GFC

Selecting pine species that are less susceptible to SPB is another key ingredient in preventing outbreaks. Loblolly, shortleaf, and Virginia pines are the three most susceptible species with white, slash, and longleaf pines being the most resistant.

What Can Be Done?

The GFC in cooperation with the US Forest Service, Forest Health Protection Unit is offering a Southern Pine Beetle Prevention and Restoration cost share program to Georgia landowners who want to reduce their risk of an SPB problem or who need to restore stands killed by SPB. The cost share program will help landowners implement various forestry practices that promote tree health thus preventing beetle infestations. The program will also assist landowners with the restoration of areas killed by SPB.

The practices that will be available to landowners are listed below.

Non-commer- Dense, over-crowded pine stands need

cial thinning to be thinned to improve the growth

(statewide) of remaining trees and to produce

a higher value

wood product

(Figure 9). A

properly thinned

stand also

reduces the rate

at which beetles

can spread.

Stands should be

thinned to a basal

area of 80 square

Figure 9 - Photo by James Johnson, GFC

feet or less.

Chemical release of pine stands (statewide)
Prescribed burning (statewide)

Hardwood species can compete with pines for water and nutrients and should be eliminated if pine vigor is to be maintained. This can be accomplished by the use of selective herbicides.
Prescribed burning reduces competing hardwoods and underbrush beneath pines. If done properly, a low
intensity fire can improve pine vigor, thus reducing the threat of a southern pine beetle infestation (Figure 10).

Figure 10 - Photo by David J. Moorhead, UGA

Pine Planting (statewide)

Planting loblolly, slash, shortleaf, and white pine at appropriate stocking levels and managing these stands at proper densities can help with vigor and natural resistance to the southern pine beetle. Matching the correct species to the site is crucial to expect good long term results and your GFC forester can help with this important decision.