From birth to death the white pine weevil chews and eats its way through various sections and levels of Colorado blue and Engelmann spruces. Each weevil attack reduces tree height growth by 40 to 60 percent each year. The recommended approach for control of the white pine weevil, Pissodes strobi, is to apply an Integrated Pest Management system (IPM) (Alfaro et al. Fertilization and weevil attack; Weevil management . Davey uses cookies to make your experience a great one by providing us analytics so we can offer you the most relevant content. The adult is a small rust-colored weevil that is about 4-6 mm long. The pupal chambers called "chip cocoons" are filled with shredded wood and can be found inside the terminal at this time. White Pine Weevil Treatment. of Forests UGA0907019b, Image 4 - White pine weevil damage to terminal P issodes strobi (Peck) E.B. Adults emerge in 10 to 15 days through small holes at the base of the dead terminal of the host plant usually in late July and August. Are new needles on your evergreen growing in brownish-red? This species kills the terminal leader primarily of eastern white pine. When mature, the larva is approximately 7 mm long, legless, and slightly C-shaped. The third weevil management strategy is to make preventative systemic insecticide applications in the fall that target the weevils as they feed on the phloem the following spring. Adults (Image 1) spend the winter in the leaf litter under or near host trees. The white pine weevil is considered the most destructive insect pest of eastern white pine in North America. For several years after successful attack by this pest, a few more laterals may grow as leaders. See White Pine Weevil from Oregon State University for more information and photographs. Most unmanaged stands have a natural crown closure of 70 to 80%. From late July to early September, those eggs emerge as adults. Mechanical Control - If excessive pitch is found, cut open the area of pitch exit and look for the larvae. The white pine weevil kills the top of conifers and is the most serious economic insect pest of white pine. Observations of resin droplets on the leader in early spring may be an indication that adults are feeding. They crawl up the trunks of nearby host trees to the terminal shoot and begin to feed before mating. Why do we need this? Colorado blue, Norway, and Serbian spruces, Scots, red, pitch, jack, and Austrian pines, and occasionally Douglas-fir are also attacked. Entering your postal code will help us provide news or event updates for your area. The white pine weevil prefers to attack trees exposed to direct sunlight. First Sign: In late March or early spring, you’ll see a shiny, sticky droplet directly below your evergreen’s bud. Application of a registered formulation of an insecticide should be made from late March through April when droplets of resin are first detected. Exit holes of at base of area damaged by White Pine Weevils. If several lateral branches are competing to be the terminal leader, all but one can be pruned away. The white pine weevil has only one generation per year, but the adults can live and continue laying eggs for several years. A second important silvicultural practice is to maintain high densities of young white pine until the trees reach about 6 m (20 ft) in height. Larvae reach maturity in mid- to late July and pupate in the infested terminal. Pine white pine weevil, white pine aphid, European pine shoot moth, Nantucket pine tip moth . Most damage is done by the larval stage. Near the apex of the front wings is a large white patch. The larvae feed on needles and also mine shoot tips, often distorting or killing back the terminals and causing trees to appear deformed. Adults grow to about 0.25 inch long and feed on shoots and needles of pine and spruce. The eggs hatch in about seven days. Pine Pales weevil, Northern pine weevil, Zimmerman pine moth Spruce eastern spruce gall adelgid, (Norway, spruce spider mite, red, black, Cooley spruce gall adelgid, white, Colorado) spruce needle miner ! 1. Prune and destroy before these are visible. Walker - Vermont Dept. The emphasis is silviculture but much pertains to nurseries. The infested terminal can be clipped, and a new leader can be trained. Apply these products at … Management: blue spruce. The worst soils for white pine are clay or poorly drained. View our Privacy Policy for more information. Knowing when to treat can be tricky. This is the result of punctures made by adults in the process of feeding and cutting egg-laying sites. The good news is infested trees are seldom killed. On occasion, they’re found on Douglas firs. Like most weevils, the adult has a long snout-like beak from which small antennae arise. White pine weevils are only threatening when white pines are young. As a goal, approximately 40 to 50% crown closure of the overstory trees should be maintained (figure 9). A very thorough presentation on the biology, ecology, and management of white pine weevil with good images. Do not contaminate forage, streams, or ponds. Rotations may be as long as 120 years for white pine, but 80 years is usually enough to produce sawlogs on good sites. The infested leaders should be pruned and burned before mid-July to destroy life stages of this pest. Handle carefully and store in original labeled containers out of the reach of children, pets, and livestock. Your best course of action is to prune trees before mid-July to remove the pests’ eggs. Management & Treatment Options Your best course of action is to prune trees before mid-July to remove the pests’ eggs. On warm spring days they fly or crawl to the leaders of suitable hosts usually during the period from mid-March through April. This should be … No single control method by itself can provide adequate pest suppression. Current insecticides useful for this treatment would include products that contain bifenthrin (Talstar, Onyx), permethrin (Astro), or cyfluthrin (Tempo). Tree Service Experts Since 1880. Walker - Vermont Dept. Often, they also attack blue, Norway and Serbian spruces. Birds may feed on larvae and pupae. Root collar weevils are typically pests of young plantations and can cause mortality by feeding on a tree's root collar. Pest description and damage White pine weevils are brown beetles with light blotches on the highly curved back. Colorado State University. The females prefer young trees to chew holes and lay eggs on the terminal leader. Adults overwinter in the forest litter and, in early spring, they emerge when the temperature rises to 2-4oC. Susceptible Trees: As their name suggests, they do prefer Eastern white pine trees. There are two ways to lessen weevil populations on young white pines in yards: 1. James F. Dill, Pest Management Specialist Clay A. Kirby, Insect Diagnostician For information about UMaine Extension programs and resources, visit extension.umaine.edu. Often, this looks like a Shepard’s crook. Authored by: Gregory A. Hoover, Sr. Extension Associate. A little white pine weevil damage is not detrimental to a young white pine's health, and the damage can simply be pruned away. Only the terminal leader needs to be sprayed. Pissodes strobi (Peck) E.B. White Pine Weevil Management in Christmas Tree Plantations Christmas trees and conifers in the landscape throughout the country are susceptible to attack from white pine weevils, Pissodes strobi(Peck) (WPW). It has irregularly shaped patches of brown and white scales on the front wings. Fertilization and weevil attack; Silvicultural methods of control. White pine weevils also can harm red, pitch, jack, Scot and Austrian pines. Or have you noticed the top of the tree is brown, drooping or curved? Effective management of the white pine weevil requires an integrated approach that ideally brings together biological, horticultural, and mechanical pest control methods with the judicious use of insecticides. *Cooley spruce gall adelgid of Douglas fir can be controlled from spring through fall when temperature is above 60 F. Non-chemical options: Only the top leader and upper branches of the tree are affected by the insect. You must have JavaScript enabled in your browser to utilize the functionality of this website. Details of the treatment ar.e presented in the following article. Fir balsam twig aphid . By continuing to use this site, you accept our use of cookies. What Is It: The white pine weevil is a dark brown beetle with white and burnt-orange spots. Damage: Come mid-June or early July, you may notice the top of your evergreen is curling and appears dead. The standard approach to manage white pine weevil is to spray insecticides in spring so that they cover the terminal. The larval stage, which lives beneath the bark, is white with a distinct brown head. Walker - Vermont Dept. * The above images are copyrighted by The University of Georgia and the individual photographers or organizations. Close planting reduces damage to Sitka spruce by the white pine weevil in the early years of a plantation. White pine weevil is native to North America and considered the most destructive insect pest of eastern white pine. !!! Damage on Scots pine and Colorado blue and Serbian spruces often extends downward through two or three year's growth. The white pine weevil is known to attack many species of pine and spruce, and occasionally Douglas-fir, but white pine is the preferred host. They’re one of the most destructive tree pests known. The manual provides readers guidance for identifying and evaluating important health problems of eastern white pine in New England, including white pine weevil, blister rust, bast scale, and needle damage, Caliciopsis canker, and red rot or red-ring rot. boxwood psyllidBoxwood. Monitor for wilting terminal shoots in early summer, and prune out and destroy infested terminal sho… Terminal killed by boring larvae of white pine weevil. of Forests UGA0907018b. View our privacy policy. White pine weevil has several naturally occurring parasitoids, such as Lonchaeid flies and wasps, but they do not provide adequate control. Get notified when we have news, courses, or events of interest to you. All Rights Reserved. The larvae also feed on the terminal bud so that the … Systemics such as imidacloprid (e.g. Larvae chew and burrow completely around the stem causing the current year's growth to wilt, droop, and eventually die. During this time feeding by adults is not considered important since little is done before they enter the leaf litter to overwinter. April (mid) PestHost. Like most weevils, the adult has a long snout-like beak from which small antennae arise. The white pine weevil is one of the most serious pests of white pine in the area. Image 1 - White pine weevil: adult Pissodes strobi (Peck) E.B. Photo by Laurie Kerzicnik. You can also band your trees or apply an insecticide to manage white pine weevils. From mid-April through early May, females mate and each deposits one to five eggs in feeding wounds (Image 2). If larvae are found, remove the entire leader. Insect parasitoids and predators as well as birds feed on this pest. That the white pine weevil causes serious damage to white pine is not news; that the weevil can be controlled effectively through the application of a poison spray which kills the female before eggs are laid is welcome news to foresters. One of the first symptoms of attack in the spring is the presence of pitch flowing from the feeding punctures in the previous year's leading shoot. They feed downward on the inner bark of the leader. By entering your email, you consent to receive communications from Penn State Extension. White pine weevils may be causing those changes. The white pine weevil - Pissodes strobi (Peck) (Coleoptera: Curculionidae) - is a native insect attacking eastern white pine (Pinus strobus L.). Therefore, thinning should be delayed. This will help the tree correct its form. Emergence holes of adult twig weevils. of Forests UGA4836010b, Image 2 - White pine weevil: pitch flow caused by feeding damage. In July look for curled, dead, or dying terminal leaders that may have the appearance of a "shepherd's crook." It has irregularly shaped patches of brown and white scales on the front wings. They lay their eggs from late April through early June. Feeding injury can also stunt or distort trees. This condition may result in a forked tree. When the terminal is heavily infested larvae (Image 3) feed side by side in a ring encircling the stem. You can also band your trees or apply an insecticide to manage white pine weevils. 3. The systemics will also kill early instar larvae as they begin tunneling in the phloem … Trees three to 20 feet tall are typically attacked. The adult weevils overwinter in the litter and emerge very early (first few warm days) in the spring to lay eggs. LEARN HOW TO STOP THE INVASIVE SPOTTED LANTERNFLY, Coronavirus: Information and resources for the Extension Community, Save For Later Print Available in Spanish, James B. Hanson, USDA Forest Service, Bugwood.org. A blue spruce disfigured due to a missing leader caused by White Pine Weevil damage. Trees become susceptible to injury when they reach a height of about three feet. Image 3 - White pine weevil: larvae Pissodes strobi (Peck) E.B. Rodents will consume overwintering adults. Merit, Xytect 2F, etc.) While eastern white and jack pine are most vulnerable, white pine weevils can develop in more than 20 tree species. White pine weevil is one of the earliest pests we treat for in the spring. Damage from white pine weevil can be prevented by spraying the upper trunk and terminals of spruce and pine in early to mid-April and again two weeks later with products that contain bifenthrin, permethrin or cyfluthrin. Dispose of empty containers right away, in a safe manner and place. White pine weevil feed on a large number of conifers including many that are planted in Christmas tree nurseries. This should promote single stem dominance on the affected host plant. White Pine Weevil Control Tips Attacks white pines, spruces More common in pure plantings Adults emerge in early spring when T > 50 F (as early as March in PA), Treat in early spring when adults emerge with borer pesticide Mechanically remove Shepard’s Crooks before August 1. By continuing to use this site, you accept our use of cookies. White Pine Weevil Fact Sheet. While they do stunt tree growth, white pine weevils do not kill your tree. This treatment is directed at the overwintered adults to kill them before they lay eggs. The first symptom evident from successful attack by this pest is glistening droplets of resin on terminal leaders of the host plant in late March and April. Susceptible species include white pines, all … Host Trees. White pine weevil damage on . Using growing degree days in the spring can be helpful to prevent damage. ©2020 The Davey Tree Expert Company. At this point the tree is now permanently crooked. Near the apex of the front wings is a large white patch. 1995) in which several tactics are combined. Walker - Vermont Dept. One of the first symptoms of White Pine Weevil. of Forests UGA0907017b. The effect of these natural enemies is not significant enough to prevent damage. Read more about the weevils and the management regimes designed for them: White Pine Weevil or Spruce Weevil (Pissodes strobi (Peck)) Warren Root Collar Weevil (Hylobius warreni (Wood)) Injury to eastern white pine and some species of spruce is usually confined to the previous year's terminal leader (Image 4). To reduce white pine weevil damage, three options are available: Open-grown plantation. Pesticides are poisonous. See All Pest, Disease and Weed Identification, See All Beer, Hard Cider, and Distilled Spirits, See All Community Planning and Engagement. Spruce northern pine weevil, Pales weevil, white pine weevil, spruce spider mite, spruce needle miner, gall adelgids . This preventative control measure should be reserved for landscapes, nurseries, or Christmas tree plantations that have a history of significant white pine weevil … Davey uses cookies to make your experience a great one by providing us analytics so we can offer you the most relevant content. When mature, the larva is approximately 7 mm long, legless, and sli… One or more side branches (laterals) may then bend and grow upward to take over as the terminal leader. The larval stage, which lives beneath the bark, is white with a distinct brown head. Feeding damage rarely kills trees but can cause multiple leaders to develop on infested trees as the terminal leader is killed. Most feeding by adults is done within 25 cm of the terminal buds. Spray Applications. If you have an evergreen, there’s a chance it could attract white pine weevils. Eucalyptus trees in California are attacked by at least 14 other introduced insects, including the bluegum psyllid (Ctenarytaina eucalypti), eucalyptus longhorned borers (Phoracantha recurva and P. semipunctata), and eucalyptus snout beetle or gumtree weevil (Gonipterus scutellatus), which are now under good biological control. JavaScript seems to be disabled in your browser. Here’s the basic info to help you identify if white pine weevils are hurting your trees. Individually, each … White Pine Weevil—Pissodes strobi The white pine weevil, which kills the top of conifers, is the most serious economic insect pest of white pine. Pissodes strobi. may be applied using soil drench or soil injection applications. View our. Adapted from Pests of Landscape Trees and Shrubs: An Integrated Pest Management Guide, University of California Statewide Integrated Pest Management Program (UC IPM). Larvae are found just under the bark of infested terminals from May through July. Stems will continue to grow in deformed. White pine is most common on well-drained, sandy soils. April (early) ! Prune all but one live lateral shoot just below the damaged terminal. Eastern white pine is most attractive to this pest when trees are less than 20 feet in height. The adult is a small rust-colored weevil that is about 4-6 mm long. 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