Insect Management in Pine Seed Orchards (Cone and Seed Insects)

Insect Management in Pine Seed Orchards (Cone and Seed Insects)

Insect Management in Pine Seed Orchards (Cone and Seed Insects)

Insect Management in Pine Seed Orchards (Cone and Seed Insects)¹
C. W. Fatzinger, W. N. Dixon, J. L. Foltz and J. R. Meeker²
Table 1. Identification and Management Practices of Insects in Pine Seed Orchards.

Symptoms of Damage
Common Name
Description of Pest

Nymphs and adults feed on female flowers of slash pine from bud-burst until pollination occurs; small resin beads present on female flowers. Flowers sometimes die or conelets and cones are distorted
Slash pine flower thrips
Slender (cigar-shaped) insects less than 3 mm long; dark brown to black in color; may be winged or wingless (adult)

Comments: Several overlapping generations per year. Develop on elongating shoots of young and mature slash pines. Adults feed on female flowers during winter.

Management Practices:
Cultural: Remove young slash pines growing adjacent to slash pine seed trees.
Chemical: Low damage level - no action. Medium to high damage level - apply a registered pesticide when female flowers are in twig-bud stage; second application one week prior to maximum flower receptivity to pollen. Use degree-day models to predict timing of different levels of attack on flowers and to predict appearance of different morphological stages of flower development
Note: An approved, chemically compatible fungicide for control of cone rust may be tank mixed with the insecticide used for the first application for thrips control.

Larvae destroy buds, shoots, flowers, and cones of pines; tunnel extensively in host material, usually push out frass and resin to surface of infested material; blisters and/or webbing may be present
Pine coneworms
Mature caterpillars are yellow-brown to purplish-brown, 16 - 25 mm length (larva)

Comments: It is important to control cone rust; rust-infected conelets are preferred feeding sites of coneworms.

Management Practices:
Chemical: Low damage level - no action. Medium to high damage level - apply a registered pesticide within 30 days following conelet closure, followed by 3-5 applications at least 30 days apart (see label). Alternation of different insecticides is usually successful in minimizing scale insect problem.
Note: Spray with a registered fungicide to prevent cone rust (see note under chemical control for slash pine flower thrips).

Larvae destroy seed in second-year pine cones. No external evidence of infestation in green cones. Mature cones contain hollowed seed packed with frass; larval tunnels are present in cone axis during winter

Pine seedworms
Mature larvae are white and less than 12 mm long

Comments: Moths lay eggs on cones in spring. Larvae feed on seeds during summer and overwinter in cone axis. One generation occurs each year.

Management Practices:
Cultural: Collect and burn all second-year cull cones soon after seed harvest.
Chemical: Low damage level - no action. Medium to high damage levels in slash pine seed orchards only - spray tree crown with a registered insecticide. Only one application is required from May 1-15.

Conelets abort or seed hollowed, discolored, often moldy inside
Pine seedbugs: Leaffooted pine seedbug (plant bug) and Shieldbacked bug
Leaffooted bug is approximately 25 mm long with leaf-like expansion on rear legs. Shieldbacked bug is 12 mm long and "stink-bug"-shaped

Comments: Shieldbacked bug has one generation per year. Leaffooted pine seedbug has several.

Management Practices:
Chemical: Low damage level - no action. Medium to high damage levels - apply registered insecticide within 30 days following conelet closure, followed by 3 to 5 applications at least 30 days apart (see label). Sprays for pine coneworms usually provide good seedbug control. Alternation of different insecticides is usually successful in minimizing scale insect problem.

Footnotes
1. This document is ENY-315, part of the 1999 Insect Management Guide, one of a series of the Department of Entomology and Nematology, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Revised: August 1998. Reviewed: October 2002. Please visit the EDIS Website at http://edis.ifas.ufl.edu.
2. C. W. Fatzinger, research entomologist (retired), USDA Forest Service, Olustee; W. N. Dixon, chief, Bureau of Entomology, Nematology, and Plant Pathology, Division of Plant Industry, Florida Department of Agriculture, Gainesville; J. L. Foltz, extension entomologist, Entomology and Nematology Department, Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida, Gainesville; and J. R. Meeker, forest entomologist, Division of Forestry, Florida Department of Agriculture and Consumer Services, Gainesville, FL.

The use of trade names in this publication is solely for the purpose of providing specific information. UF/IFAS does not guarantee or warranty the products named, and references to them in this publication does not signify our approval to the exclusion of other products of suitable composition. Use pesticides safely. Read and follow directions on the manufacturer's label.

The Institute of Food and Agricultural Sciences (IFAS) is an Equal Opportunity Institution authorized to provide research, educational information and other services only to individuals and institutions that function with non-discrimination with respect to race, creed, color, religion, age, disability, sex, sexual orientation, marital status, national origin, political opinions or affiliations. For more information on obtaining other extension publications, contact your county Cooperative Extension service.

U.S. Department of Agriculture, Cooperative Extension Service, University of Florida, IFAS, Florida A. & M. University Cooperative Extension Program, and Boards of County Commissioners Cooperating. Larry Arrington, Dean.

Copyright Information
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Symptoms of Damage	Common Name	Description of Pest
Nymphs and adults feed on female flowers of slash pine from bud-burst until pollination occurs; small resin beads present on female flowers. Flowers sometimes die or conelets and cones are distorted	Slash pine flower thrips	Slender (cigar-shaped) insects less than 3 mm long; dark brown to black in color; may be winged or wingless (adult)
Comments: Several overlapping generations per year. Develop on elongating shoots of young and mature slash pines. Adults feed on female flowers during winter.
Management Practices: Cultural: Remove young slash pines growing adjacent to slash pine seed trees. Chemical: Low damage level - no action. Medium to high damage level - apply a registered pesticide when female flowers are in twig-bud stage; second application one week prior to maximum flower receptivity to pollen. Use degree-day models to predict timing of different levels of attack on flowers and to predict appearance of different morphological stages of flower development Note: An approved, chemically compatible fungicide for control of cone rust may be tank mixed with the insecticide used for the first application for thrips control.
Larvae destroy buds, shoots, flowers, and cones of pines; tunnel extensively in host material, usually push out frass and resin to surface of infested material; blisters and/or webbing may be present	Pine coneworms	Mature caterpillars are yellow-brown to purplish-brown, 16 - 25 mm length (larva)
Comments: It is important to control cone rust; rust-infected conelets are preferred feeding sites of coneworms.
Management Practices: Chemical: Low damage level - no action. Medium to high damage level - apply a registered pesticide within 30 days following conelet closure, followed by 3-5 applications at least 30 days apart (see label). Alternation of different insecticides is usually successful in minimizing scale insect problem. Note: Spray with a registered fungicide to prevent cone rust (see note under chemical control for slash pine flower thrips).
Larvae destroy seed in second-year pine cones. No external evidence of infestation in green cones. Mature cones contain hollowed seed packed with frass; larval tunnels are present in cone axis during winter	Pine seedworms	Mature larvae are white and less than 12 mm long
Comments: Moths lay eggs on cones in spring. Larvae feed on seeds during summer and overwinter in cone axis. One generation occurs each year.
Management Practices: Cultural: Collect and burn all second-year cull cones soon after seed harvest. Chemical: Low damage level - no action. Medium to high damage levels in slash pine seed orchards only - spray tree crown with a registered insecticide. Only one application is required from May 1-15.
Conelets abort or seed hollowed, discolored, often moldy inside	Pine seedbugs: Leaffooted pine seedbug (plant bug) and Shieldbacked bug	Leaffooted bug is approximately 25 mm long with leaf-like expansion on rear legs. Shieldbacked bug is 12 mm long and "stink-bug"-shaped
Comments: Shieldbacked bug has one generation per year. Leaffooted pine seedbug has several.
Management Practices: Chemical: Low damage level - no action. Medium to high damage levels - apply registered insecticide within 30 days following conelet closure, followed by 3 to 5 applications at least 30 days apart (see label). Sprays for pine coneworms usually provide good seedbug control. Alternation of different insecticides is usually successful in minimizing scale insect problem.

Insect Management in Pine Seed Orchards (Cone and Seed Insects)1

Footnotes

Copyright Information

Insect Management in Pine Seed Orchards (Cone and Seed Insects)¹