Neodiprion sertifer

(Geoffroy, 1785)

European pine sawfly, red pine sawfly, redheaded pine sawfly

Neodiprion sertifer is a native to Europe that was accidentally introduced to North America in 1925, where it has become an established forest pest. emerge in late summer or early autumn and females lay in pine needles using a saw-like ovipositor. Larvae feed gregariously on pine needles and possess a chemical defense mechanism: they store pine resins in specialized gut pouches and regurgitate them when threatened. The overwinters in the egg stage rather than as cocoons, distinguishing it from many .

Neodiprion sertifer (Diprionidae) - (larva), Loonse en Drunense Duinen, the Netherlands by

This image is created by user Wim Rubers at Waarneming.nl, a source of nature observations in the Netherlands.
. Used under a CC BY 3.0 license.

Neodiprion sertifer 289042606 by Gilles San Martin. Used under a CC BY-SA 4.0 license.

Pine needles closterocerus ruforum by Sorneguer. Used under a CC BY-SA 3.0 license.

Pronunciation

How to pronounce Neodiprion sertifer: //ˌniː.oʊˈdɪp.ri.ɒn ˈsɜr.tɪ.fɜr//

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Identification

Larvae have creamy white bodies with rows of black spots and red or scarlet . are -like and stingless. The can be distinguished from similar Neodiprion species by larval coloration and by its with -stage . A larval identification key for eastern North American conifer sawflies is available in Davis et al. (2023).

Images

Habitat

Coniferous forests and plantations, particularly those containing Scots pine (Pinus sylvestris), red pine, Jack pine, Japanese pines, and Crimean pine (Pinus nigra subsp. pallasiana). Found in both natural forests and managed landscapes including urban and suburban areas with ornamental plantings.

Distribution

Native to Europe (Austria, Belgium, Britain, Czechoslovakia, Denmark, Finland, France, Germany, Hungary, Italy, Netherlands, Norway, Poland, Portugal, Romania, Spain, Sweden, Switzerland, Yugoslavia); also recorded in Japan, Korea, Turkey, and Russia. Introduced to North America in 1925; established in Canada (Ontario) and the United States.

Seasonality

emerge from cocoons in late summer or early autumn (September–October). are laid in autumn and overwinter. Larvae hatch from early April to late May. Cocoon stage occurs in summer, with adult timed to autumn regardless of when larval feeding concluded.

Diet

Larvae feed on pine needles (folivory). Young larvae feed on needles from the edge inward, consuming approximately half the needle and leaving a dry sliver; older larvae consume entire needles. pines include Scots pine, red pine, Jack pine, Japanese pines, and Crimean pine.

Life Cycle

with one per year. overwinter in pine needles. Larvae hatch in spring (April–May), feed gregariously, then spin cocoons in summer. emerge from cocoons in autumn (September–October) to mate and oviposit. Unlike such as N. lecontei and N. swainei, this does not overwinter in the cocoon stage.

Behavior

Larvae are gregarious, feeding in groups throughout most of their development. Group feeding may facilitate access to tender needle tissue once one larva breaches the tough needle surface. When disturbed, larvae arch their backs and regurgitate a droplet of sticky, odorous pine resin from specialized gut pouches as an anti- defense. This secretion deters spiders, ants, and birds.

Ecological Role

Herbivore and folivore on conifers; serves as prey for birds and for multiple including Lophyroplectus luteator (Ichneumonidae) and Bracon hebetor (Braconidae). Natural enemies typically help moderate .

Human Relevance

Significant forest pest in North America following its 1925 introduction. can defoliate thousands of acres, though trees rarely die from defoliation alone; growth stunting is the primary damage. Managed through (natural ), manual removal of clusters, or application during the larval stage. Spinosad, , and bassiana have shown efficacy in control studies.

Similar Taxa

Neodiprion leconteiRedheaded pine sawfly; larvae have similar red but is multivoltine with 2+ per year and overwinters in cocoons rather than
Neodiprion swaineiOverwinters in cocoon stage rather than ; different seasonal
Diprion piniEuropean pine ; distinguished by oviposition and response to larval oral secretions (D. pini is deterred by N. sertifer secretions, while N. sertifer is not)