Southern Pine Beetle Aerial Survey Procedures

Introduction

Although the southern pine beetle (SPB) is a native insect that is often controlled by natural factors, SPB infestations have a remarkable potential to grow rapidly (edges of infested spots can expand by >50 feet/day) and cause extensive pine mortality under certain conditions Because of this damage potential, the Division of Forestry conducts annual aerial detection surveys to record the location and size of SPB "spots" (groups of infested trees) These aerial surveys should be accompanied by ground checks and notifications to landowners/managers about the need to control expanding SPB spots as soon as possible Early and rapid detection (and subsequent control) of SPB spots is critical to preventing the development of outbreaks, and for minimizing damage when outbreaks do occur.

Timing and Frequency of Flights

Each DOF District within the known range of SPB (Districts 1-12) is responsible for conducting at least one SPB aerial detection survey of all its counties each calendar year In most years, this initial aerial survey is to be conducted in late May or early June in accordance with a memorandum (issued in May) to the District/Center Managers Earlier surveys may be requested by the Forest Entomologist for areas where winter/spring SPB infestations are discovered, or in areas where moderate to outbreak levels of activity are predicted by the spring Pheromone Trap Survey Forecast

If no SPB spots are detected during the initial May/June aerial survey, no additional SPB aerial surveys need to be conducted, unless SPB spots are later detected and confirmed through another means (e.g., response to a landowner call, ground detection, detection on a wildfire survey flight, etc.)

If SPB spots are detected on the initial flight, or detected later through other means, follow-up aerial surveys should be conducted monthly until no new spots are identified In counties experiencing outbreaks with rapid initiation of new spots, flights should be conducted every 2-3 weeks until no new spots develop Follow-up flights can be discontinued after November 1^st In counties that experienced active SPB spots during the year, at least one aerial flight should be conducted during late December-mid January; otherwise flights are to resume with the initial May/June survey. (top)

Area of Coverage

The manner in which each District is covered in the survey is up to the discretion of the District Manager or an SPB Coordinator designated by the Manager Managers may choose to have each county forester survey their own county, or to have pairs or groups of counties (where feasible) surveyed in a single flight Regardless of whether counties are surveyed individually or in groups, SPB spot data should be reported to the Forest Health Section on a county-by-county basis (see Reporting section below) Aerial surveyors should attempt to cover all of the susceptible host type (pine areas) in a given county; areas where pine is notably absent or very sparse may be omitted Close attention should be given to mature, over-mature, and/or high density stands of loblolly pine Loblolly pine stands in flood plains or along watercourses are notorious locations for SPB infestations and therefore should be checked closely. (top)

Survey Procedure

As long as the primary goals of the aerial survey are achieved, the specifics of the procedure can vary depending on the preferences and judgment of the forester(s) and pilot involved The primary goals of the flight are 1) to detect most or all potential SPB spots in a given county, 2) roughly estimate the size of each spot, 3) record the location of each spot such that it can be visited on the ground and identified in follow-up flights, and 4) determine whether previously-detected spots have substantially expanded, been controlled, or gone inactive The following general guidelines are offered for achieving these goals:

Equipment:
The observer(s) should consider taking the following items in flight:

Maps (or aerial photos) of the area

Pencil(s) or grease pencil(s) for marking photos/maps

GPS Unit

Notepad and/or small tape recorder

Air sickness sack or canister; air sickness remedy

Flight pattern, altitude, conditions: To help ensure adequate coverage of the county/area, parallel flight lines (N/S or E/W) may be drawn on the map(s) prior to the flight and discussed with the pilot Spacing of flight lines will vary depending on the distance each observer is able to accurately scan The following table indicates the percent of an area that can be surveyed given two observers, one surveying from each side of the plane:

Interval between flight lines	Percent coverage if each observer can scan a distance of :
	½ mile	1 mile	1 ¼ mile
1 mile	100	-	-
2 miles	50	100	-
2 ½ miles	40	80	100
5 miles	20	40	50
from Billings and Ward 1984, "How to Conduct a Southern Pine Beetle Aerial Survey"

Ideally, flights should be conducted on clear days with low wind velocities and minimal haze, and at an altitude ranging from 1000 to 3000 feet Lower altitudes allow a greater ability to detect small spots, while higher altitudes can allow for better visual orientation and location of landmarks Flights should be conducted between 9:00 am and 3:00 pm to avoid long shadows, and should not last more than 4 hours without landing to avoid observer fatigue.

Recognizing SPB spots:

SPB spots usually appear as distinct clusters of dying or dead-and-dying pines New spots that have just become visible from the air may have only light green or yellow-crowned trees Older spots will have trees in various stages of attack, grading in appearance from needleless (vacated by SPB) to red-topped (mostly vacated), to yellow- and light green-topped (actively infested), to green-topped trees (recently infested) that are indistinguishable from unattacked trees The color of the crowns in the spot can indicate if, how rapidly, and in what direction the spot is spreading See An Aerial Observer's Guide to Recognizing and Reporting Southern Pine Beetle Spots for more information.

Recording spot location and size:

The location and size of all spots with 6 or more red-topped pines and adjacent yellow-crowned faders should be recorded Spots with fewer trees or only yellow-crowned trees may be recorded at the observer's discretion if they look suspiciously like developing SPB spots Spots should be plotted as polygons or points on a map or photo so that they can be located on the ground and monitored on subsequent flights If possible, have the pilot fly over the spot and record the lat/long coordinates using a GPS unit Also, roughly estimate and record the size of the spot in acres (or fractions of acres), either in the plane or later based on the size of the polygons drawn on the map Acreage estimates can be adjusted after the ground check if necessary. (top)

Assigning ground check priorities:

If detected SPB spots are so numerous that available personnel and time will not permit ground checks on all spots, use the following table to help assign ground check priorities to each detected SPB spot Ground check priority numbers can be recorded directly on the sketch map:

Priority for Ground Check	Spot Classification
Priority 1 (high)	More yellow than red-crowned trees In dense natural pine stand or in area with past history of SPB outbreaks Easy access or high salvageable volume In plantation or other high value area Threat to cross property lines and affect high value stands
Priority 2 (breakout)	Yellow-crowned trees in spot previously reported controlled or inactive
Priority 3 (medium)	More red-crowned than yellow-crowned trees Poor access or moderate salvageable volume
Priority 4 (low)	Few yellow-crowned trees Infested pines surrounded by hardwoods or open land Difficult to locate on ground because of small size or inaccessibility In unmerchantable timber or with low salvageable volume
from Billings and Ward, 1984 "How to Conduct a Southern Pine Beetle Aerial Survey"

For additional information and guidelines on SPB survey procedures, consult How to Conduct a Southern Pine Beetle Aerial Detection Survey by the Texas Forest Service. (top)

Landowner Notifications and Ground Checks

Identify the landowner of suspect spots within five days after the flight. After identifying the landowner, immediately (or within two days at the latest) notify the landowner of the potential SPB activity on his or her property by letter, phone, in person, or otherwise. Over the years, individual counties have developed procedures and form letters to tailor this notification process to their own situation. For sample letters or suggested notification materials, contact the Forest Health Section office.

Ideally, do a ground check (i.e. visit the site to confirm the presence of SPB) on all newly detected spots as soon as possible and before the next follow-up flight. However, when spots are numerous, you may have to prioritize ground checks using the criteria listed in the table above, or based on landowner familiarity with/capability of dealing with SPB.

The primary goals of the ground check are to 1) confirm that the spot is actually an SPB spot rather than mortality caused primarily by another bark beetle, insect, disease, or causal agent, 2) evaluate the likelihood of spot expansion based on presence of active and freshly-attacked trees 3) delineate a control buffer strip around the active portion of spots, and 4) collect some basic stand measurement data at the spot. Detailed guidelines for these activities can be found in A Field Guide for Ground Checking Southern Pine Beetle Spots, USDA Agriculture Handbook 558. If the landowner resides at the property, the ground check is also an opportune time to discuss the situation with him/her and provide information about control options.

During the ground check, take a few moments to roughly estimate and record the following spot parameters and information:
• Predominant pine species
• Avg. Basal area, height, and diameter - (don't cruise the stand, just use 1-2 prism plots or ocular estimates)
• Predominant market size class (pulpwood, chip-n-saw, or sawtimber)
• Landform (bottomland/flatwoods, sandhill/ridge, or other terrain)
• STR or lat/long coordinate
• Adjust estimates of spot size if needed
• Note whether the spot is active, inactive, or has been controlled.

Spots should be aerially surveyed or revisited at monthly intervals following detection until they are controlled or inactive. (top)

Reporting

Use the SPB Activity Excel Spreadsheet to periodically record and report SPB spot/infestation data to the Forest Entomologist on a county basis. This reporting can be done by the county forester(s) or others assigned the responsibility by the District/Center Manager or SPB coordinator. The spreadsheet is intended to be a tool for the forester to keep track of activity in his/her county, as well as provide the Forest Health Section with data on the extent and volume of SPB impact in the state (as required by our Regional USDA Forest Service cooperators). The spot parameter data is used to determine what types of stands are most vulnerable to SPB in Florida.

Update and submit the completed Excel spreadsheet to the Forest Entomologist monthly during active years, or by November of inactive years. The spreadsheet can be saved electronically and emailed. Because the spreadsheet contains embedded formulas, do not alter its format. Instructions for completing the spreadsheet are included on one of the spreadsheet 'tabs'. Drop-down menus are programmed into many of the columns to avoid typing. Please contact the forest Entomologist with any questions regarding the spreadsheet or reporting procedure. (top)

Online References

The handbooks referenced in the above text are located at the following website managed through the University of Georgia's Bugwood Network: http://www.barkbeetles.org/spb.html

Last Updated 24 March '04, Bud Mayfield, DOF Forest Entomologist. (top)