When trees are not under stress, they will generally respond to SPB attack by producing moderate to copious amounts of resin or pitch which flows out of the bark from the entrance holes produced by attacking beetles. Different species of pine produce different amounts and colors of pitch. Loblolly pine generally produces white or pink color pitch in sufficient amounts to detect from a distance of 10 to 20 ft. Shortleaf pine produces red pitch in small amounts which in some cases requires close inspection to detect. Virginia pine, longleaf pine, and slash pines generally produce the largest amount of pitch in response to bark beetle attack.
Pond pine produces copious amounts of red-colored pitch.
Pines under stress or suffering from drought may produce no pitch at all. So remember that pitch tubes are not always present. If pitch tubes are yellow in color , hard to the touch and crumble when crushed in the hand, the tree is not a fresh attack. Often, pines that were attacked in the fall, although killed by SPB, do not change color until the following Spring. yet. It is easiest to find a pitch tube and follow it into the tree.