“Differences in stem form and bark anomalies of northern red oak trees in forest stands in Canada and Germany”

Northern red oak wood is valuable for a variety of applications not only in its natural distribution range in North America, but also in Europe. Timber quality and stem diameter largely determine timber prices and respective uses. Silvicultural management is key to influencing tree growth and stem quality. In Germany, crop tree thinning is currently the standard treatment, while in Canada the shelterwood system is common practice. The objective of this study was to compare stem characteristics related to stem quality of northern red oaks from Canada with those from Germany to determine effects of different silvicultural treatments on stem quality. We examined stem characteristics from a total of 150 dominant northern red oaks in Canadian and German forest stands using the terrestrial laser scanning approach. Northern red oak stems in Canada (shelterwood system) were significantly straighter, whereas German stems (crop tree thinning approach) were significantly smoother on the surface and rounder on the upper parts of the stems (height 4 – 8 m). The number of bark anomalies decreased with increasing tree competition, indicating that competition is the main driver influencing external stem form and the occurrence or persistence of bark anomalies.

Re-description and systematic re-appraisal of the genus Kokkocynips Pujade-Villar & Melika, (Hymenoptera: Cynipidae: Cynipini), including new combinations of Nearctic species and the description of a new species from Panama

The monophyly and taxonomic validity of some currently accepted genera of gall wasps in the Cynipini (Hymenoptera: Cynipidae) are being challenged by recent systematic studies. Here we used morphological and molecular data to re-describe and revise the taxonomic limits of the monotypic genus Kokkocynips Pujade-Villar & Melika, previously recorded only from Mexico. We describe a new species from Panama, Kokkocynips panamensis Medianero & Nieves-Aldrey, reared from galls on Quercus salicifolia Neé, and add new records from Mexico for the type species of the genus K. doctorrosae Pujade-Villar. Six Nearctic species, Dryocosmus rileyi (Ashmead, 1896), D. imbricariae (Ashmead, 1896), D. coxii (Basset, 1881), D. deciduus (Beutenmueller, 1913), Callirhytis difficilis (Ashmead, 1887) and C. attractans (Kinsey, 1922) are transferred to Kokkocynips. Species of Kokkocynips are associated only with red oaks (Quercus section Lobatae (Fagaceae)) and are distributed in the Nearctic and Neotropical regions, from Canada through Mexico and Panama. Taxonomic limits of Kokkocynips are discussed in light of the molecular phylogenetic relationships of the studied species. Diagnostic characters, gall description, distribution, and biological data of Kokkocynips species are given, including a key for the identification of the asexual generations of seven species.

Canopy spectral reflectance detects oak wilt at the landscape scale using phylogenetic discrimination

The oak wilt disease caused by the invasive fungal pathogen Bretziella fagacearum is one of the greatest threats to oak-dominated forests across the Eastern United States. Accurate detection and monitoring over large areas are necessary for management activities to effectively mitigate and prevent the spread of oak wilt. Canopy spectral reflectance contains both phylogenetic and physiological information across the visible near-infrared (VNIR) and short-wave infrared (SWIR) ranges that can be used to identify diseased red oaks. We develop partial least square discriminant analysis (PLS-DA) models using airborne hyperspectral reflectance to detect canopies at early stages of disease development and assess the importance of VNIR, SWIR, phylogeny, and physiology for oak wilt detection. We achieve high accuracy through a three-step phylogenetic process in which we first distinguish oaks from other species (90% accuracy), then red oaks from white oaks (Quercus macrocarpa) (93% accuracy), and, lastly, infected from non-infected trees (80% accuracy). Including SWIR wavelengths increased model accuracy by ca. 20% relative to models based on VIS-NIR wavelengths alone; using a phylogenetic approach also increased model accuracy by ca. 20% over a single-step classification. SWIR wavelengths include spectral information important in differentiating red oaks from other species and in distinguishing diseased red oaks from healthy red oaks. We determined the most important wavelengths to identify oak species, red oaks, and diseased red oaks. We also demonstrated that several multispectral indices associated with physiological decline can detect differences between healthy and diseased trees. The wavelengths in these indices also tended to be among the most important wavelengths for disease detection within PLS-DA models, indicating a convergence of the methods. Indices were most significant for detecting oak wilt during late August, especially those associated with canopy photosynthetic activity and water status. Our study suggests that coupling phylogenetics, physiology, and canopy spectral reflectance provides an interdisciplinary and comprehensive approach that enables detection of forest diseases at large scales even at early disease stages. These results have potential for direct application by forest managers for early detection to initiate actions to mitigate the disease and prevent pathogen spread.

Description of three new species of oak gallwasps of the genus Amphibolips Reinhard from Mexico (Hymenoptera, Cynipidae)

Three new species of oak gall wasps of the genus Amphibolips Reinhard, 1865 (Hymenoptera: Cynipidae: Cynipini) are described from Mexico: Amphibolips magnigalla Nieves-Aldrey & Castillejos-Lemus, Amphibolips kinseyi Nieves-Aldrey & Castillejos-Lemus and Amphibolips nigrialatus Nieves-Aldrey & Castillejos-Lemus. The specimens of the first two species were representative of sexual generations and come from the State of Oaxaca, while only a female, collected in the State of Veracruz, is described for A. nigrialatus. The new species induces galls on Quercus zempoaltepecana and Q. sapotifolia (Fagaceae, section Lobatae, red oaks). Descriptions of the diagnostic morphological characteristics of the three species and a key for their identification are provided. The taxonomic relationships of the new species with other species of Amphibolips are discussed; the three new species are closely allied amongst themselves and are related to A. dampfi Kinsey, 1937. With the three newly-described species, the number of Amphibolips in Mexico is increased to 23.

IMPROVEMENT, GREEN CONSTRUCTION AND LANDSCAPE DESIGN AS AN ACTUAL ECOLOGICAL CHALLENGE OF YOUTH

The quality of life in the urban system is closely associated with environmental conditions. With the right use of design tools, it is possible to solve the environmental problems of youth through the impact of landscape design on human opinion. Such landscaping areas as territories of memorable historical places must be complied with the modern requirements of society to preserve historical memory. It is discussed in the article the issues of solving problems to improve the factors of the urban environment that have a positive impact on maintaining intergenerational ties. The relevance of the project "Living memory of the Great Victory: for the glory of life, unity and the future" is grounded on the beautification and landscape design of Armavir. It is described a new ecological landscape approach to the planting of greenery and improvement of memorial complexes, based on the creation of a natural, relatively sustainable ecosystem. It is described the concept of laying park sites, performing cognitive, patriotic, informational, and environmental functions. The proposed style of memorial park territories supports the general historical and local history orientation of the territory in the design and improvement of urban areas with minimal resources for planting red oaks, based on the independent cultivation of seedlings from acorns. Ecological and patriotic project is aimed at creating and maintaining a sustainable landscape structure.

Evaluating Economic Impacts of Prescribed Fire in the Central Hardwood Region

Surface fires are often prescribed to favor oak (Quercus) regeneration in eastern forests, but there is potential for fire to damage residual overstory timber. This study evaluated the potential economic effects of prescribed fire on sawtimber volume and value across 139 stands, each with a known history of one to six prescribed fires, on the Hoosier, Mark Twain, Wayne, and Daniel Boone National Forests. Sawtimber volume and value losses were highly variable, ranging from 0 to 2,269 bd ft ac–1 and from US$0 to US$272.95 ac–1, respectively, for stands that had received at least one prescribed fire. Volume and value losses increased linearly by +0.9 percent and +1.5 percent per burn, respectively, that a stand received over the past 25 years. Stands with south-facing aspects had greater relative volume and value losses (+1.4 to +1.5 percent, respectively), but this influence was statistically less important than the number of burns in predictive models. The eastern national forests had much lower average relative volume and value losses, <3.0 percent, than the more western Mark Twain National Forest (10–15 percent loss). Species composition affected value loss associated with prescribed fire; red oaks experienced significantly higher value loss than all other species groups.

Effects of burn season on large seedlings of oak and other hardwood regeneration three years after shelterwood harvest

The effects of fall and spring prescribed fires on large seedlings (0.3 to 1.3 m height) of oak and other hardwood species three years after a shelterwood harvest were examined in Richland Furnace and Zaleski State Forests in southern Ohio. Fall and spring burns appeared to be more deleterious to red oaks (Quercus rubra L., Q. velutina Lam., Q. coccinea Muenchh.) than white oaks (Q. alba L., Q. prinus L.). Red oak experienced reductions in numbers and canopy volume after spring burns, and canopy reductions after fall burns. White oak experienced small increases in numbers of stems after both fall and spring burns, and an increase in the canopy volume after fall burns, but a slight decrease after spring burns. Yellow-poplar (Liriodendron tulipifera L.), a major oak competitor prior to fire, experienced dramatic reductions in the number of regenerating stems and canopy volume after both fall and spring burns. On the other hand, red maple (Acer rubrum L.) experienced large increases in the number of regenerating stems and canopy volume after both fall and spring burns. Based on importance value, the oak species remained relatively unchanged after both fall and spring burns. Yellow-poplar became the least dominant species after spring burns and the second to last dominant species after fall burns.

First Description of the Adult Male of the Gall-Like Scale Insect Allokermes galliformis (Riley) (Hemiptera: Coccomorpha: Kermesidae)

The adult male of Allokermes galliformis (Riley, 1881) (Hemiptera: Coccomorpha: Kermesidae) is described for the first time in Colorado, United States of America. This scale insect species recently emerged as a significant pest of red oaks in Colorado through its causative role in drippy blight disease. A description and illustration of the adult male characterize its key external morphological characteristics.