Anthracnose is one of the most common and important foliage diseases of shade trees in Iowa. Symptoms of anthracnose are often referred to as “leaf blights” or “leaf spots” and are most serious on sycamore, ash, maple, white and bur oak, and walnut. Linden, hickory, elm, red and black oak, and other deciduous trees also are susceptible, although anthracnose is less common and damaging on these ...

Bacterial wetwood is a major cause of value loss in the red oak lumber industry in the United States. Red oak trees in Mississippi, South Carolina, and Florida were sampled and evaluated for certain chemical properties possibly associated with the wetwood condition. Specific variables investigated were pH and concentmtions of methane, cations (Na+. Ca++, K+, and Mg++). nonstructural carbohydrat...

Oaks are dominant and key tree species in Mediterranean forest ecosystems. However, recent decades, oak forests have been heavily impacted by decline, a worldwide phenomenon exacerbated climate change. The charcoal disease agent Biscogniauxia mediterranea is involved the decline of formations variety contexts. Here, we investigated impact role B. oaks Castelfidardo Forest, relict wood late Holo...

Using a historical reconstruction, we discovered a potential trophic cascade involving cougar (Puma concolor), mule deer (Odocoileus hemionus), and California black oak (Quercus kelloggii) in the Yosemite Valley of Yosemite National Park in California. Our objective was to determine whether large deer populations in the absence of a top-level carnivore were suppressing tree regeneration. As hum...

BACKGROUND Wild birch trees grow in limited areas in Japan and are not a common aero-allergen. However, many patients who do not live in the area show positive birch pollen Radioallergosorbent Test (RAST). Therefore, being sensitized by another tree pollen which is closely related to birch may result in showing a specific IgE antibody to birch. Alder is a one of these trees and in the past it g...

In the Mediterranean evergreen oak woodlands of southern Portugal, the main tree species are Quercus ilex ssp. rotundifolia Lam. (holm oak) and Quercus suber L. (cork oak). We studied a savannah-type woodland where these species coexist, with the aim of better understanding the mechanisms of tree adaptation to seasonal drought. In both species, seasonal variations in transpiration and predawn l...

Oak Regeneration Dynamics Successful regeneration of oak on intermediate and high-quality sites (upland oak site index > 65 to 70 feet) is limited due to the lack of the vigorous advance regeneration and/or saplings/pole-sized trees that are capable of sprouting. Vigorous advance regeneration and/or stump sprouters are required at the time of regeneration on intermediate and highquality sites, ...

This paper reports on five years of observations in a case-control study examining the role of tree and site factors on the development of Phytophthora ramorum stem canker (sudden oak death) in coast live oak (Quercus agrifolia) and tanoak (Lithocarpus densiflorus). In September of each year from 2000 through 2004, we collected data on P. ramorum symptoms, tree condition, midday stem water pote...

BACKGROUND Agrilus bigutattus (Fabricius) is a forest pest of increasing importance in the United Kingdom. The larvae damage weakened native oaks and are thought to contribute to premature tree death. Suspected links with acute oak decline (AOD) are not yet confirmed, but AOD-predisposed trees appear to become more susceptible to A. biguttatus attack. Thus, management may be necessary for contr...