beetles, and ambrosia beetles. Several large outbreaks have occurred in Florida and 
Texas; however, they subsided after one or two seasons. Starvation and reduced 
reproductive capability of the females are among the factors that help bring 
outbreaks to an end. The ichneumonid, Endasys subclavatus (Say), is an effective 
parasite attacking cocoons spun in the litter and topsoil (342), while the pteromalid, 
Dibrachys cavus (Walker), commonly attacks cocoons spun above ground. 
The slash pine sawfly. NV. merkeli Ross, is known to occur in Georgia, Florida, 
Mississippi, and on Grand Bahama Island. Both varieties of slash pine are hosts in 
the United States, and Caribbean pine is infested in the Bahamas. Full-grown 
female larvae are 25 to 30 mm long, with brown subdorsal and supraspiracular 
stripes, and two widely separated, black semioval spots near the posterior end. The 
head is 2.3 to 2.5 mm wide, reddish above the eyes and sooty black below. This 
two-tone coloration is most evident in alcohol-preserved larvae. Eggs are laid in 
growing, current year’s needles, with a row of 10 to 15 egg pockets typically 
underlying the flat side of a needle, beginning at the fascicle sheath (/294). 
Winter is spent as a prepupa in dark mahogany-brown cocoons usually spun in 
the soil. Adult emergence occurs approximately during May, July, and September 
in Florida. Larvae feed only on old foliage during the growing season, but may 
completely defoliate trees during the fall when the largest populations typically 
develop. Extensive fall outbreaks have occurred in 5- to 10-year-old open planta- 
tions growing on periodically flooded flatwood sites in Florida and Mississippi, 
subsequently resulting in greatly reduced tree growth when defoliation exceeds 90 
percent per tree. Outbreaks in south Florida have been terminated within one 
growing season by a nuclear polyhedrosis virus disease. Flies in the genus 
Spathimeigenia are important parasites attacking mature, feeding larvae (342), and 
Villa sinuosa sinuosa (Wiedemann) is an important cocoon parasite during 
droughts. Chance flooding of cocoons immediately following adult sawfly 
emergence resulted in complete mortality of parasitoids within cocoons, followed 
by a large outbreak of this sawfly in south Florida. 
A number of other species of Neodiprion also occur in eastern forests: N. 
nigroscutum Middleton occurs on jack pine in the Lake States and Ontario. Mature, 
feeding larvae have reddish-brown heads, unbroken subdorsal and supraspiracular 
stripes, and arcuate markings above the legs. An epiproctal spot is not present (8/). 
N. pinusrigidae (Norton) feeds on pitch pine from New Jersey to Maine. Full- 
grown feeding larvae are dull green with a black head, solid black subdorsal stripe, 
and broken black lateral stripe. Sometimes a double row of black dots occurs below 
each lateral stripe. N. hetricki Ross has been observed feeding on loblolly pine in 
Virginia and North Carolina and pond pine in South Carolina. Mature, feeding 
larvae have black heads, black subdorsal stripes, and black lateral stripes that may 
be either broken or solid. There is a single generation each year in Virginia, with 
females depositing overwintering eggs during October (564). N. compar (Leach) is 
reported from southeastern Canada, Virginia, Georgia, and Florida. Known hosts 
include red and jack pines in Canada and longleaf pine in Florida. Mature feeding 
larvae from Florida are pale green, with barely discernible longitudinal stripes. The 
pale-amber head bears a yellow triangular spot within a large black pentagonal 
marking. N. maurus Rohwer occurs on jack pine in southeastern Canada and the 
Lake States. 
The genus Diprion is represented by only one species in the United States and 
Canada, and this species is of foreign origin. 
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