Knowledge of the community structure of ectomycorrhizal fungi among successional forest age-classes is critical for conserving fungal species diversity. Hypogeous and epigeous sporocarps were collected from three replicate stands in each of three forest age-classes (young, rotation-age, and old-growth) of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) dominated stands with mesic plant association groups. Over four fall and three spring seasons, 48 hypogeous and 215 epigeous species or species groups were collected from sample areas of 6300 and 43 700 m2, respectively. Cumulative richness of hypogeous and epigeous species was similar among age-classes but differed between seasons. Thirty-six percent of the species were unique to an age-class: 50 species to old-growth, 19 to rotation-age, and 25 to young stands. Seventeen species (eight hypogeous and nine epigeous) accounted for 79% of the total sporocarp biomass; two hypogeous species, Gautieria monticola Harkn., and Hysterangium crassirhachis Zeller and Dodge, accounted for 41%. Average sporocarp biomass in young and rotation-age stands compared with old-growth stands was about three times greater for hypogeous sporocarps and six times greater for epigeous sporocarps. Average hypogeous sporocarp biomass was about 2.4 times greater in spring compared with fall and for epigeous sporocarps about 146 times greater in fall compared with spring. Results demonstrated differences in ectomycorrhizal fungal sporocarp abundance and species composition among successional forest age-classes.Key words: ectomycorrhizal fungi, sporocarp production, forest succession, Pseudotsuga menziesii, Tsuga heterophylla zone, biodiversity.

Exotic pathogens and pests threaten ecosystem service, biodiversity, and crop security globally. If an invasive agent can disperse asymptomatically over long distances, multiple spatial and temporal scales interplay, making identification of effective strategies to regulate, monitor, and control disease extremely difficult. The management of outbreaks is also challenged by limited data on the actual area infested and the dynamics of spatial spread, due to financial, technological, or social constraints. We examine principles of landscape epidemiology important in designing policy to prevent or slow invasion by such organisms, and use Phytophthora ramorum, the cause of sudden oak death, to illustrate how shortfalls in their understanding can render management applications inappropriate. This pathogen has invaded forests in coastal California, USA, and an isolated but fast-growing epidemic focus in northern California (Humboldt County) has the potential for extensive spread. The risk of spread is enhanced by the pathogen's generalist nature and survival. Additionally, the extent of cryptic infection is unknown due to limited surveying resources and access to private land. Here, we use an epidemiological model for transmission in heterogeneous landscapes and Bayesian Markov-chain-Monte-Carlo inference to estimate dispersal and life-cycle parameters of P. ramorum and forecast the distribution of infection and speed of the epidemic front in Humboldt County. We assess the viability of management options for containing the pathogen's northern spread and local impacts. Implementing a stand-alone host-free “barrier” had limited efficacy due to long-distance dispersal, but combining curative with preventive treatments ahead of the front reduced local damage and contained spread. While the large size of this focus makes effective control expensive, early synchronous treatment in newly-identified disease foci should be more cost-effective. We show how the successful management of forest ecosystems depends on estimating the spatial scales of invasion and treatment of pathogens and pests with cryptic long-distance dispersal.

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The effects of initial leaf litter chemistry on first-year decomposition rates were studied for 16 common Pacific Northwest conifers, hardwoods, and shrubs at the H.J. Andrews Experimental Forest in western Oregon. Leaf litters were analyzed for C, N, P, K, Ca, Mg, proximate organic fractions (nonpolar, polar, acid-hydrolyzable extractives, acid-hydrolyzable lignin, and acid-unhydrolyzable residue, previously termed "Klason lignin"), and biochemical components (total phenolics, reactive polyphenols, water-soluble carbohydrates, water-soluble proanthocyanidins, and water- and acid-unhydrolyzable proanthocyanidins). By including measurements of reactive and residual phenolic fractions and acid-hydrolyzable lignin, these analytical methods improve upon traditional proximate leaf litter analyses. Significant differences in litter chemistries and decomposition rates were found between species. For all species combined, the 1-year decay rate (k) values had highly significant correlations (P < 0.001) with 30 out of the 36 initial chemistry variables tested in this study. The three highest correlations were with acid-unhydrolyzable proanthocyanidins, lignocellulose index, and acid-unhydrolyzable residue (r = 0.83, –0.81, –0.80, respectively, with P < 0.0001 and n = 339). We found that no single litter chemistry variable was a universal predictor of the 1-year k value for each of the individual 16 species studied, though phenolic components were more frequent significant (P < 0.001) predictors of decomposition rate.

Forty-two percent of California's forests and rangelands are privately owned (34 million acres). These lands provide important ecosystem services such as carbon sequestration, pollination and wildlife habitat, but little is known about the people who own and manage them. We surveyed forest and rangeland owners in California and found that these long-time landowners value their properties for their natural amenities and as a financial investment. Owners of large properties (500 or more acres) were significantly more likely to use their land for income production than owners of smaller properties, and they were also more likely to carry out or be interested in environmental improvements. Many forest and rangeland owners reported they had been previously approached to sell their land for development. Only about one-third had participated in conservation programs; few had conservation easements. This survey can help guide outreach and education efforts, and the development of information, policies, programs and financial incentives for landowners.A survey of forest and rangeland property owners in California found that the vast majority value their land for its natural beauty, and they voluntarily undertook environmental improvements and management practices. Above, an exurban development in coastal California.