Subsequent or simultaneous pruning of laterals and forks can aid the trees in forming a nearly straight main stem. They have the characteristic and prominent hooked snout of the weevil. In preparing the present revision we have used information currently available as well as incorporated some information contained in the earlier versions of this leaflet. Remove any damaged or highly susceptible trees surrounding the plantation before planting. The remaining dead leader provides a pathway for disease organisms. 0000045630 00000 n Using binoculars is helpful for those short in stature. Details of the life cycle of P. strobi (figure 4) have been studied by many researchers. The adults hibernate in the duff underneath host trees. Don’t get it twisted. 1986. They also appear to prefer thicker bark, which increases the survival of immature stages. Planting trees grown from various geographic seed sources indicates that variation in susceptibility to weevil attacks could be used to reduce the probability of planting highly susceptible trees. When resin droplets are found, scrape away the sap to reveal if there is a circular feeding site. by Orchard Park Tree Service | Oct 14, 2019 | Diseases & Insect Damage. Also, damaged trees are more susceptible to disease, especially heartwood rot. The southern pine root weevil Hylobius aliradicis, occasionally damages the roots of seedling and sapling- sized loblolly and slash pines in southern Georgia. Use insecticides in Christmas tree plantings (see appendix). James F. Dill, Pest Management Specialist Clay A. Kirby, Insect Diagnostician For information about UMaine Extension programs and resources, visit Large pine weevil can cause significant damage to newly planted, immature forests during the first five years following restocking if the sites are left unmanaged. 0000006471 00000 n The white pine weevil (Pissodes strobi Peck): Its biology and control. This insect doesn’t just harm Eastern white pines but also goes after all other types of pines and spruces too. When eggs are mature, the female chews a fresh hole in the bark and scoops out cambial tissue to create a small egg niche. However, young trees may be affected if found next to fields with high pressure. Revised March 1995Formatted for the Internet September 1997, USA: 1051 Clinton Street, Buffalo, NY 14206, All Prices in USD. x�b```f``����� �� Ȁ ��@Q�% �� Infested terminals should be destroyed or removed from the site. A number of other similarly marked Pissodes species may be confused withP. 0000012745 00000 n Finally, part of the dead leader usually persists for many years (figure 8) and may act as a point of entry for heart rot organisms such as Phellinus pini Ames, the major heart rot disease of older eastern white pines. 0000010208 00000 n 1930. Phillips TW, Lanier GN. By the end of the season, larval feeding may extend below one or more whorls of branches. to do the work safely and correctly. This is especially important in open-grown plantations or stands. Sap droplets seeping from feeding or egg holes. Pissodes strobi has one generation each year. Regenerate white pine in mixture with hardwoods. A single weevil can lay over 100 eggs. Chip cocoon. Sticky substances should be applied on tape or other material, not directly on the bark. Because use of pesticides is regulated by the Federal Government and by each respective State, before purchasing a pesticide check with local authorities, county agents, a University Cooperative Extension Service, or an Agricultural Experiment Station for current local use status. In more significant trees, pruning is not a DIY option, so contact an. 0000002434 00000 n Ottawa, ON: Department of the Environment, Canadian Forestry Service. Two to three weeks later, eggs are laid in new punctures that do not produce resin droplets. They pupate in wood chip cocoons similar to the other weevils (Figure 18). The pales weevil, Hylobius pales, (Figure 14) prefers loblolly, shortleaf, pitch, and white pine seedlings. 9). Circular holes, 2 to 3 mm (.10 to .12 inch) in diameter, on an infested stem indicate that adults have emerged. Insecticides labeled for application on spruce trees to control bark beetles or wood-boring beetles probably also would kill white pine weevils, but it is University of Idaho policy only to recommend products that specifically include both the target plant (spruce trees) and the target pest (white pine weevil). In the summertime, affected leaders can be pruned back to get rid of parts possibly containing weevil larvae. Figure 7 - A "bushy" open-grown white pine, showing the effect of numerous attacks by the white pine weevil. Silvicultural Practices To Reduce Weevil Damage. The needles on the affected stem will turn yellowish-green, then reddish-brown, and will eventually fall off. The wood chip cocoons made by the larvae are readily visible underneath the bark of infested trees (Figure 18). Recommended material include cyfluthrin (sold as Bayer Advanced Yard and Garden Spray), when the adults first emerge from leaf litter in early to mid-April. Damaged leaders should not be used to train new leaders. Copyright 2020, Sign up for our newsletter to receive special offers and promotions. Its feeding damage can kill a young tree if it girdles the stem (trunk), and a large population of weevils can kill thousands of young trees on a newly restocked site. The emerging adults feed on the bark and underlying tissues of newly planted trees. It is also known as the Engelmann spruce weevil and the Sitka spruce weevil. Because of the short residue properties of most insecticides, it is important that applications be well synchronized with periods of peak adult activity. When the injury becomes too severe to manage with pruning, treat the entire plantation. However, eastern white pine is the most suitable host for brood development. Delaying treatments results in poor control. Douglas-fir 4. In some areas, the pest is called the Sitka spruce weevil or Engelmann spruce weevil because of preference for these hosts: White pine weevil adults have long snouts typical of all weevils. Spray applications must be made promptly. Larvae feeding on vascular tissue. The white pine weevil in New Hampshire.