Treesearch

Understanding crown rise and sapwood taper will help meet management objectives such as producing long branch-free boles for clear wood and old-growth restoration, or producing sawlogs with a high proportion of heartwood. Coast redwood (Sequoia sempervirens) tree crown ratio data were collected 20 years after partial harvesting in a 65-year-old second growth stand. Crown ratio correlated with stand density and relative tree height, and differed between stand interior and edge locations. The sum of tree crown lengths in each plot gave crown length/ac which exhibited an asymptotic relationshi...

The role technology plays in outdoor recreation is evolving and of ongoing interest. One technology-related activity in particular emerged at the start of the 21st century: geocaching. Geocaching involves using a handheld GPS device to find hidden caches in areas based on clues posted on the Internet. Geocaching.com, the primary source for geocachers, provides information and guidelines for participating in the activity. In 2010, geocaching celebrated its 10th birthday heralded by nearly 100,000 geocaching. com members and nearly 1,000,000 active caches around the world. The current...

The research reported here includes a number of studies conducted in southern California. It was aimed at better understanding the recreation needs and desires of Latino populations. Generally, the findings indicate that Latinos have many of the same recreation needs as other groups, such as places to recreate and reasonable accommodations. But it also indicates they have some unique preferences.

The red turpentine beetle (RTB), Dendroctonus valens LeConte (Coleoptera: Curculionidae: Scolytinae), is a secondary pest of pines in its native range in North and Central America. Outbreaks and tree mortality attributed to RTB alone are rare in its native range. RTB was introduced into China in the early 1980s and spread rapidly from Shanxi Province to four adjacent provinces; it has infested over 500,000 ha of pine forest and has caused extensive tree mortality since 1999. We provide a historical background on RTB outbreaks, explanations for its invasive success, management options, and...

DISRUPT Micro-Flake Verbenone Bark Beetle Anti-Aggregant flakes (Hercon Environmental, Inc., Emigsville, Pennsylvania) were applied in two large-scale tests to assess their efficacy for protecting whitebark pine Pinus albicaulis Engelm. from attack by mountain pine beetle Dendroctonus ponderosae Hopkins (Coleoptera: Scolytinae) (MPB). At two locations, five plots of equivalent size and stand structure served as untreated controls. All plots had early- to mid-outbreak beetle populations (i.e. 7.1-29.2 attacked trees/ha). Verbenone was applied at 370 g/ha in both studies. Intercept traps...

Currently, techniques for managing western pine beetle, Dendroctonus brevicomis LeConte (Coleoptera: Curculionidae, Scolytinae), infestations are limited to tree removals (thinning) that reduce stand density and presumably host susceptibility, and/or the use of insecticides to protect individual trees. There continues to be significant interest in developing an effective semiochemical-based tool for protecting trees from D. brevicomis attack, largely as an alternative to conventional insecticides. The responses of D. brevicomis to tree volatiles and verbenone were documented in eight...

Bark beetles (Coleoptera: Curculionidae, Scolytinae) are commonly recognized as important tree mortality agents in coniferous forests of the western U.S.A. High stand density is consistently associated with bark beetle infestations in western coniferous forests, and therefore, thinning has long been advocated as a preventive measure to alleviate or reduce the amount of bark beetle-caused tree mortality. The objective of this study was to determine the effectiveness of thinning to reduce stand susceptibility to bark beetle infestations over a 10-year period in Pinus jeffreyi forests on the...

Ambermarked birch leafminer, Profenusa thomsoni (Konow) (Hymenoptera: Tenthredinidae), is an exotic, invasive pest of urban and wildland birch, Betula spp., in portions of North America. Extensive defoliation of ornamental birch in Alaska requires that suitable control measures be evaluated and developed. Based on previous work, we evaluated the efficacy of emamectin benzoate (TREE-äge ®, Syngenta Crop Protection LLC, Greensboro, NC) for control of P. thomsoni in Interior Alaska. TREE-äge ® significantly reduced crown damage (percent leaf mining) compared to the untreated control. It...

In his new book, Bob Cabin uses his personal involvement in the restoration of Hawai'i dry forests to illustrate the tensions that he feels exists between the science and practice of ecological restoration. It is a journey that starts out among the multidisciplinary, multi-interest perspectives associated with a grass-roots communitybased working group (Part 1, Chapter 1-3), moves into the tedium of academic rigor (Part 1, Chapter 4-5), and culminates in an "aha!" moment, when he realizes that science is of limited value for restoration (Part 1, Chapter 6). His final resting point is...