Find more of our publications and books at extensionpubs.umext.maine.edu. Dispose of empty containers right away, in a safe manner and place. Here’s the basic info to help you identify if white pine weevils are hurting your trees. They crawl up the trunks of nearby host trees to the terminal shoot and begin to feed before mating. Because of the multiple ways a weevil uses a blue spruce during its life cycle, a multi-step approach is necessary for white pine weevil treatment. Observations of resin droplets on the leader in early spring may be an indication that adults are feeding. The eggs hatch in about seven days. Insect parasitoids and predators as well as birds feed on this pest. Exit holes of at base of area damaged by White Pine Weevils. This condition may result in a forked tree. Walker - Vermont Dept. In July look for curled, dead, or dying terminal leaders that may have the appearance of a "shepherd's crook." Trees three to 20 feet tall are typically attacked. Trees become susceptible to injury when they reach a height of about three feet. Susceptible species include white pines, all … 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. of Forests UGA4836010b, Image 2 - White pine weevil: pitch flow caused by feeding damage. It has irregularly shaped patches of brown and white scales on the front wings. Are new needles on your evergreen growing in brownish-red? Or have you noticed the top of the tree is brown, drooping or curved? Therefore, thinning should be delayed. This preventative control measure should be reserved for landscapes, nurseries, or Christmas tree plantations that have a history of significant white pine weevil … A little white pine weevil damage is not detrimental to a young white pine's health, and the damage can simply be pruned away. ©2020 The Davey Tree Expert Company. 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. It has irregularly shaped patches of brown and white scales on the front wings. Management & Treatment Options Your best course of action is to prune trees before mid-July to remove the pests’ eggs. On occasion, they’re found on Douglas firs. * The above images are copyrighted by The University of Georgia and the individual photographers or organizations. 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. Individually, each … The white pine weevil is considered the most destructive insect pest of eastern white pine in North America. The infested terminal can be clipped, and a new leader can be trained. Walker - Vermont Dept. The white pine weevil is one of the most serious pests of white pine in the area. Why do we need this? From birth to death the white pine weevil chews and eats its way through various sections and levels of Colorado blue and Engelmann spruces. Only the terminal leader needs to be sprayed. Walker - Vermont Dept. This should be … The infested leaders should be pruned and burned before mid-July to destroy life stages of this pest. 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. Pest description and damage White pine weevils are brown beetles with light blotches on the highly curved back. Pissodes strobi (Peck) E.B. Larvae chew and burrow completely around the stem causing the current year's growth to wilt, droop, and eventually die. Walker - Vermont Dept. The white pine weevil prefers to attack trees exposed to direct sunlight. Authored by: Gregory A. Hoover, Sr. Extension Associate. 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. Rodents will consume overwintering adults. Most feeding by adults is done within 25 cm of the terminal buds. Details of the treatment ar.e presented in the following article. The worst soils for white pine are clay or poorly drained. 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 ! One of the first symptoms of Knowing when to treat can be tricky. Near the apex of the front wings is a large white patch. Injury to eastern white pine and some species of spruce is usually confined to the previous year's terminal leader (Image 4). Susceptible Trees: As their name suggests, they do prefer Eastern white pine trees. Management: blue spruce. The recommended approach for control of the white pine weevil, Pissodes strobi, is to apply an Integrated Pest Management system (IPM) (Alfaro et al. During this time feeding by adults is not considered important since little is done before they enter the leaf litter to overwinter. of Forests UGA0907018b. The standard approach to manage white pine weevil is to spray insecticides in spring so that they cover the terminal. !!! For several years after successful attack by this pest, a few more laterals may grow as leaders. The white pine weevil has only one generation per year, but the adults can live and continue laying eggs for several years. White pine weevil feed on a large number of conifers including many that are planted in Christmas tree nurseries. Pissodes strobi. They’re one of the most destructive tree pests known. *Cooley spruce gall adelgid of Douglas fir can be controlled from spring through fall when temperature is above 60 F. As a goal, approximately 40 to 50% crown closure of the overstory trees should be maintained (figure 9). Each weevil attack reduces tree height growth by 40 to 60 percent each year. The White Pine Weevil. The adult weevils overwinter in the litter and emerge very early (first few warm days) in the spring to lay eggs. Hundreds of eggs may be deposited in one terminal leader. Image 1 - White pine weevil: adult Pissodes strobi (Peck) E.B. Application of a registered formulation of an insecticide should be made from late March through April when droplets of resin are first detected. Adults grow to about 0.25 inch long and feed on shoots and needles of pine and spruce. On warm spring days they fly or crawl to the leaders of suitable hosts usually during the period from mid-March through April. Adults (Image 1) spend the winter in the leaf litter under or near host trees. 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. Pine white pine weevil, white pine aphid, European pine shoot moth, Nantucket pine tip moth . Adapted from Pests of Landscape Trees and Shrubs: An Integrated Pest Management Guide, University of California Statewide Integrated Pest Management Program (UC IPM). April (early) ! 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. Like most weevils, the adult has a long snout-like beak from which small antennae arise. The larvae also feed on the terminal bud so that the … Handle carefully and store in original labeled containers out of the reach of children, pets, and livestock. View our. Do not contaminate forage, streams, or ponds. 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. If several lateral branches are competing to be the terminal leader, all but one can be pruned away. While they do stunt tree growth, white pine weevils do not kill your tree. 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. White pine weevil is one of the earliest pests we treat for in the spring. The effect of these natural enemies is not significant enough to prevent damage. At this point the tree is now permanently crooked. Prune and destroy before these are visible. Damage on Scots pine and Colorado blue and Serbian spruces often extends downward through two or three year's growth. The adult is a small rust-colored weevil that is about 4-6 mm long. The emphasis is silviculture but much pertains to nurseries. White Pine Weevil. 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). Most damage is done by the larval stage. From late July to early September, those eggs emerge as adults. The pupal chambers called "chip cocoons" are filled with shredded wood and can be found inside the terminal at this time. 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. The good news is infested trees are seldom killed. Adults overwinter in the forest litter and, in early spring, they emerge when the temperature rises to 2-4oC. 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. of Forests UGA0907019b, Image 4 - White pine weevil damage to terminal P issodes strobi (Peck) E.B. First Sign: In late March or early spring, you’ll see a shiny, sticky droplet directly below your evergreen’s bud. The systemics will also kill early instar larvae as they begin tunneling in the phloem … Feeding damage rarely kills trees but can cause multiple leaders to develop on infested trees as the terminal leader is killed. Apply these products at … White pine is most common on well-drained, sandy soils. When mature, the larva is approximately 7 mm long, legless, and slightly C-shaped. Host Trees. The white pine weevil is considered the most destructive insect pest of eastern white pine in North America. Often, this looks like a Shepard’s crook. Emergence holes of adult twig weevils. View our privacy policy. Davey uses cookies to make your experience a great one by providing us analytics so we can offer you the most relevant content. You can also band your trees or apply an insecticide to manage white pine weevils. You can also band your trees or apply an insecticide to manage white pine weevils. Fir balsam twig aphid . 1995) in which several tactics are combined. 1. 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