Enter up to 15 characters for the name of the spot. Characters may include letters, numbers, special characters, and spaces. The name of the spot will appear as a label on graphical or numerical output. Top of Help Page
Enter the date when the infestation was surveyed. The model has only been validated for infestations beginning in May through October ( Lih and Stephen 1989), but I've allowed for the selection of a beginning date as early as April, because infestations occasionally occur that early. The year is unimportant aside from indicating a leap year, so there is a broad range of acceptable years, anywhere from 1500 to 3000 AD. Top of Help Page
Select a Southeastern U.S. state. The model has only been validated for Alabama, Arkansas, Louisiana, Mississippi, and Texas ( Lih and Stephen 1989). Other Southeastern states have been included because southern pine beetle infestations often occur in those states as well. The state is important in approximating latitude and longitude, which are useful in the temperature calculation. However, the state is not generally an important factor in the model, so if an infestation occurs in a state that is not listed, select a neighboring state instead. Top of Help Page
Enter the number of trees that were infested by southern pine beetle earlier this season, but are now dead. You may enter an integer in the range 0-9000. To learn more about how to identify dead and infested trees, check out the easy-to-read USDA Agriculture Handbook No. 558.
If you like, you can enter zero for the number of previously infested trees. Then in the graphical or numerical outputs, the number of dead trees would not represent the number of dead trees killed since the beginning of this season, but rather the number of trees killed since the ground-check date. Top of Help Page
Enter the number of currently infested trees. You may enter an integer in the range 1-9000. To learn more about how to identify dead and infested trees, check out the easy-to-read USDA Agriculture Handbook No. 558. Top of Help Page
Enter the number of trees infested with each of the different development stages of southern pine beetle. You may enter an integer in the range 0-9000 for the numbers of trees infested by each development stage.
If you do not know how many trees are infested with each development stage, set the numbers of trees in each infestation stage to 0.
If you do know how many trees are infested with each development stage, be sure that the numbers of trees infested with each development stage sum to the total number of currently infested trees.
To learn more about how to identify the stages of infested trees, check out the easy-to-read USDA Agriculture Handbook No. 558. Also be sure to look at this Virginia Tech page on southern pine beetles, including development stage identification. Brood adults include callow and mature adults. Top of Help Page
Enter the proportion of loblolly in the infested stand. This is a real number between 0.0 and 1.0. It is calculated by dividing the number of infested loblolly pine trees in the stand by the total number of infested trees in the stand (loblolly/total).
A good site for tree identification is North Carolina State University's Native pines of Eastern North America , specifically loblolly pine. Top of Help Page
Enter the mean diameter at breast height (DBH) of the infested trees in the stand. This is a real number between 12.0 and 77.0 cm or between 5.0 and 30.0 inches. Be sure to select the correct units. For information on how to measure DBH, see the University of Minnesota's page on Estimating Tree Diameter. Top of Help Page
Enter the pine basal area of the infested and healthy trees in the stand. This is a real number between 2.0 and 69.0 square meters per hectare, or between 10.0 and 300.0 square feet per acre. Be sure to select the correct units.
For information on how to measure basal area, see North Carolina State University's page on thinning pine stands, under the heading "How To Measure Stand Density." It might be a good idea to contact your local forester for help if this is your first time measuring basal area. Top of Help Page
Enter the hardwood basal area of the stand. This is a real number between 0.0 and 69.0 square meters per hectare, or between 0.0 and 300.0 square feet per acre. Be sure to select the correct units.
For information on how to measure basal area, see North Carolina State University's page on thinning pine stands, under the heading "How To Measure Stand Density." It might be a good idea to contact your local forester for help if this is your first time measuring basal area. Top of Help Page
Enter the number of days for which the model should predict numbers of dead and infested trees. This is an integer in the range 1 to 92. The model has been validated for up to 92 days ( Lih and Stephen 1989). Top of Help Page
Select whether you would like to graph Dead and/or Infested trees. Infested trees still contain southern pine beetles. Dead trees are all trees that have been killed by southern pine beetles. It is assumed that all trees that are infested at the beginning of the simulation will die, so the initial number of infested trees is added to the number of dead trees. Top of Help Page
Select the beetle populations desired for graphing. Initial Attacking Adults are the adult beetles that are attacking trees at the beginning of the simulation, whereas Attacking Adults are the second and following generations of adult beetles attacking trees. Parent Adults are those beetles that have successfully entered the tree and have mated, but have not left the tree. Eggs and Larvae and Pupae are the immature stages of the southern pine beetles. Brood Adults include callow and newly mature adults. Emerging Adults are adults that are currently leaving the tree. Top of Help Page
Select a format for the simulation output.
If you choose Graphical output, a graph will appear in the left frame of your browser, depicting either dead and infested trees over time, or populations of southern pine beetles over time.
To save graphical output in Netscape or Internet Explorer in Windows, right click on the image and choose "Save Image As" or a similar option. In a MacIntosh operating system, hold down the CTRL key while clicking on the image, and a "Save Image As" option should appear.
If you choose an HTML table, an HTML table will appear in a new window. The table will contain all input and output data, including dead and infested trees as well as populations of southern pine beetles over time. Choosing Comma-delimited text will produce the same information as the HTML table, but in a format that you can copy and paste into a spreadsheet for further data manipulation.
To save tabular output, use the "Save As" option in your web browser's file menu. Top of Help Page