Seasonal Variations in Activity of the Southern Pine Beetle in East Texas

1964 ◽  
Vol 57 (6) ◽  
pp. 840-842 ◽  
Author(s):  
R. C. Thatcher ◽  
L. S. Pickard
1978 ◽  
Vol 2 (2) ◽  
pp. 62-64 ◽  
Author(s):  
James C. Kroll ◽  
Hershel C. Reeves

Abstract Eleven climatic variables, recorded during the period 1966-76, were used to develop a multiple linear regression model for predicting potential number of southern pine beetle (SPB) infestations for east Texas. Four climatic variables were significantly (P < 0.05) related to numbers of SPB infestations. These were (1) mean temperature for February of current year, (2) total rainfall for previous summer, (3) total rainfall for previous fall, and (4) total rainfall for previous spring. The regression analysis accounted for 90.7 percent of the variation in yearly numbers of SPB infestations.


1981 ◽  
Vol 5 (1) ◽  
pp. 7-10 ◽  
Author(s):  
Ray R. Hicks ◽  
James E. Howard ◽  
Kenneth G. Watterston ◽  
Jack E. Coster

Abstract A ranking system developed in east Texas classifies the susceptibility of host stands to southern pine beetle (Dendroctonous frontalis Zimm.) into four categories. Input variables include pine basal area per acre, average tree height, and a categorical evaluation of land form. Higher-hazard stands are generally overstocked, have taller trees, and grow on wet or low-lying sites. Management strategies are recommended for the various hazard categories.


1979 ◽  
Vol 2 ◽  
pp. 269-283 ◽  
Author(s):  
Ray R. Hicks ◽  
James E. Howard ◽  
Kenneth G. Watterston ◽  
Jack E. Coster

1979 ◽  
Vol 25 (4) ◽  
pp. 547-556
Author(s):  
Roy L. Hedden ◽  
Ronald F. Billings

Abstract The influence of selected forest site and stand factors on the rate of expansion of individual infestations (spots) of southern pine beetle (Dendroctonus frontalis) was studied during the summer months of 1975-77 in east Texas. In small spots (≤20 active trees), further expansion seldom occurred, presumably due to an insufficient quantity and distribution of brood to perpetuate necessary pheromone production. Similarly, the proportion of spots that had declined to less than 20 active trees after 1 month (day 30) was inversely related to number of active trees at first visit (day 0). In expanding spots, the number of additional trees killed per day was significantly and positively correlated with number of active trees per spot and stand basal area. In addition, mean rates of summer spot growth varied among years in direct relation to areawide beetle population levels in east Texas which increased to outbreak levels and then collapsed over the 3-year study period. This emphasizes the need to include some measure of beetle population level and/or aggressiveness in future spot growth models. No correlation was found between number of brood trees per spot at the first visit and stand basal area at the spot origin. These findings support the following hierarchy of priorities for direct control: Priority 1--spots with &gt;100 active trees, even in sparse stands; Priority 2--spots with 20-100 active trees in high basal area stands; Priority 3--spots with 20-100 active trees in low basal area stands; Priority 4--spots with ≤20 active trees. During the summer, small spots, particularly those lacking freshly attacked trees (pheromone source), have a high probability of soon going inactive without control. Forest Sci. 25:547-556.


1978 ◽  
Vol 2 (1) ◽  
pp. 19-22 ◽  
Author(s):  
R. L. Hedden

Abstract Since 1955 commercial forest land in east Texas has declined 6 percent while growing stock volume per acre has almost doubled. At the same time, the southern pine beetle population has increased tenfold. It is postulated that increasing numbers of high-density pine stands susceptible to southern pine beetle attack have become available for infestation. This trend will continue for at least 20 to 30 years. At present, the only method available to land managers to reduce the risk of timber loss to the southern pine beetle is to practice intensive forest management.


2008 ◽  
Vol 37 (3) ◽  
pp. 650-659 ◽  
Author(s):  
N. A. Friedenberg ◽  
S. Sarkar ◽  
N. Kouchoukos ◽  
R. F. Billings ◽  
M. P. Ayres

2020 ◽  
Author(s):  
Stephen R Clarke ◽  
Jessica Hartshorn

Abstract The southern pine beetle (SPB) Dendroctonus frontalis Zimmermann, is the most important insect pest of pines in the southeastern United States, with outbreaks often resulting in thousands of hectares of pine mortality. Natural enemies and competitors have been cited as significant regulators of SPB populations and, therefore, outbreaks. A recent outbreak on the Homochitto National Forest (NF) in Mississippi provided an opportunity to undertake a case study comparing population fluctuations of SPB, its major predator Thanasimus dubius, and its competitors, Ips bark beetles. Trap catches of all three were tracked through the course of the outbreak on the Homochitto NF as well as in two other forests with low or no SPB activity. The number of predators collected initially increased on the Homochitto NF in response to the SPB outbreak, but their impact on reducing infestation numbers was unclear. Numbers of Ips trapped were similar across all three forests, indicating that other factors were regulating SPB populations. The outbreak only lasted a single year, and its brevity likely limited the availability of host resources for natural enemy and competitor populations. Additional studies are warranted to explore the mechanisms affecting the extent and duration of SPB outbreaks, such as active forest management. Study Implications: The widespread application of cut-and-leave treatments during a short duration southern pine beetle (SPB) outbreak on the Homochitto National Forest did not result in immediate increased collections of Ips bark beetles, competitors of SPB. Similar population trends of Ips bark beetles in areas with and without SPB infestations suggest that other factors, such as climate, regulate population numbers. Low numbers of the main SPB predator, Thanasimus dubius, immediately preceded an outbreak, and trap collections increased after outbreak onset, reaffirming the importance of this natural enemy in SPB population fluctuations.


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