Culturable microfungi inhibitory to Armillaria rhizomorph formation from Fagus sylvatica stump roots and soil

Culturable fungi from 28 fungal communities were isolated from soil, rhizosphere and thick (1 cm diam.) roots of living beech (Fagus sylvatica) trees and their stumps 1–3 years after felling. All fungi were morphotyped and identified morphologically. The frequency of fungi was 2–5× greater in stumps than in living trees. The diversity of fungi was similar in living trees and stumps. The majority of fungal species that occurred at greater frequency on/in roots of stumps reduced the growth of Armillaria ostoyae and to a smaller extent of A. gallica rhizomorphs in a soil substrate in vitro. It is suggested that the mycobiota of roots may constrain the colonization of F. sylvatica by A. ostoyae rather than by A. gallica. The significance of these findings in the epidemiology of Armillaria in beech forests is discussed.     

Rhizospheric streptomycetes as potential biocontrol agents of <Emphasis Type="Italic">Fusarium</Emphasis> and <Emphasis Type="Italic">Armillaria</Emphasis> pine rot and as PGPR for <Emphasis Type="Italic">Pinus taeda</Emphasis>

Pinus taeda is one of the main timber trees in Brazil, occupying 1.8 million ha with an annual productivity of 25–30 m³ ha⁻¹. Another important species is Araucaria angustifolia, belonging to the fragile Rainforest biome, which for decades has been a major source of timber in Brazil. Some diseases that affect the roots and/or the stem of these trees and cause “damping-off” of the seedlings, with economic and environmental losses for the forest sector, are caused by the plant pathogenic fungi Fusarium sp. or Armillaria sp. This research project intended to isolate actinobacteria from the Araucaria rhizosphere, which present an antagonistic effect against these fungi. After the selection of the best pathogen inhibitors, morphologic characteristics, enzyme production, and their effect on the growth of Pinus taeda were studied. The actinobacteria were tested for their antagonistic capacity against Fusarium sp. in Petri plates with PDA as substrate. The inhibition zone was measured after 3, 5, 7, and 10 days. Of all the isolates tested, only two of them maintained inhibition zones up to 4 mm for 10 days. The inhibition of Armillaria sp. was tested in liquid medium and also in Petri dishes through the evaluation of the number of the fungal rhizomorphs in dual culture with the actinobacteria. It was found that all five isolates were able to inhibit the rhizomorph production, with the best performance of the isolate A43, which was capable of inhibiting both fungi, Fusarium and Armillaria. In a greenhouse experiment, the effect of five isolates on the growth of Pinus taeda seedlings was tested. Plant height, stem diameter, root and shoot dry matter were determined. The Streptomyces isolate A43 doubled plant growth. These results may lead to the development of new technologies in the identification of still unknown bacterial metabolites and new management techniques to control forest plant diseases.     

Population ecology of yew (<Emphasis Type="Italic">Taxus baccata</Emphasis> L.) in the Central Apennines: spatial patterns and their relevance for conservation strategies

Understanding the ecological mechanisms that allow a species to transition from an occasional understory component to the dominant type in the forest canopy is essential for predicting future shifts in the distribution of species. We investigated this issue with regard to yew, also because mature yew trees have been reported to inhibit self-regeneration and seedling survival, prompting concerns for the long-term preservation of the species. Our objectives were (a) to quantify spatial patterns of yew (Taxus baccata L.) populations near the southern limit of the species’ ecological distribution, (b) to determine the relationships between yew presence and topographic gradients, and (c) to answer the question of how yew regeneration is affected by such patterns and relationships. We analyzed three extensive yew populations (90–165 ha, including 3–12 thousand established individuals) that mostly occupy the understory of beech forests located in protected areas of the central Apennines (Italy). Overall, the realized niche of yew (either as established trees, saplings, or seedlings) followed the expected bell-shaped curve of a species response to an environmental gradient. Yew was mainly found at 1,000–1,600 m elevation on mesic exposures (north and west) and intermediate slopes (30–60%). Geostatistical analysis revealed that yew occurred in patches, as shown by variogram ranges of 40–110 m for yew tree basal area and regeneration abundance. Yew regeneration over the landscape was directly related to basal area of yew trees. At local scales (~10 m), presence of established trees favored regeneration in relatively less developed stands, whereas high density of mature yews suppressed regeneration. Healthy yew populations in beech forests had a minimum size of 0.5–3 ha. As yew density increased within these patches, regeneration dropped, so that yew conservation cannot be limited to presently occurring populations, despite the longevity and potential for vegetative reproduction of the species. Disturbance from grazing and wildfire was also found to impact yew survival. Long-term existence of yew in the Italian Apennines depends on maintaining and expanding old-growth beech forests that incorporate yew patches, and have a minimum continuous cover equivalent to a relatively undisturbed regime (10–50 ha).     

Characteristics of Night Sleeping Trees of Proboscis Monkeys (<Emphasis Type="BoldItalic">Nasalis larvatus</Emphasis>) in Sabah,Malaysia

Primates spend about half of their lives at sleeping sites, and their choice of sleeping sites may affect individual survival. We identified a total of 88 trees used by proboscis monkeys (Nasalis larvatus) as night sleeping sites on 16 nights from June to September 2008 in riverine, mangrove, and mixed mangrove–riverine forests along the Garama River, a tributary of the Klias River, in the west of Sabah, Malaysia. We recorded 11 variables for each tree, including the species, physical structure, distance from the riverbank, and connectivity with surrounding trees. We compared sleeping trees with 114 trees with ≥30 cm girth at breast height (GBH) located ≤50 m of the riverbank in 8 botanical plots (total 1 ha). Trees in the plots represented the general vegetation patterns of the study area. Choice of sleeping trees did not depend on the tree species. Although sleeping trees included trees ≤46 m from the river, those closer to riverbanks (5–35 m, n = 76) were more likely to be used as sleeping sites. Compared to the available trees, sleeping trees had larger trunks (mean±SD = 143.6 ± 56.9 cm GBH), and were taller (mean±SD = 34.3 ± 8.1 m), with greater number (median = 6; range = 12) and larger (mean±SD = 24.1 ± 15.2 cm circumference) main branches. They were also located near to other trees, with overlapping branches, creating good arboreal connectivity. Choice of sleeping trees by proboscis monkeys is likely to be related to risks of predation and injury from falling, as well as ease of social interaction and efficiency of locomotion.     

Genetic population structure of three Armillaria species at the landscape scale: a case study from Swiss Pinus mugo forests

Armillaria species are plant pathogens that cause Armillaria root rot and are known to cause mortality of mountain pines (Pinus mugo) in the Swiss National Park in the Central Alps. The identity of isolates and the spatially explicit population structure of the Armillaria species were investigated in a 3.3 km² study area in the Swiss National Park. In total, 242 Armillaria isolates, 205 from wood samples and 37 from epiphytic rhizomorphs, were collected. Species were identified using haploid–diploid pairings and genets were determined using intraspecific somatic incompatibility tests. The population structure differed markedly among the Armillaria species. A. cepistipes and A. borealis mainly occurred as genets of small spatial extent (mean 0.2 ha, and 0.6 ha), whereas A. ostoyae formed significantly larger genets (mean 6.8 ha). The largest A. ostoyae genet extended over approx. 37 ha. Several disease centres associated with Heterobasidion annosum were found to be embedded within large Armillaria genets. The extension of large A. ostoyae genets suggests that forests that occupy the study area have developed in the presence of these Armillaria genets. The finding of large Armillaria genets supports the assumption that large genets occur in areas with cold climate and little precipitation.     

Biological species ofArmillaria and their mycoparasitic associations withRhodophyllus abortivus in Hokkaido

Specimens of basidiomes and/or rhizomorphs ofArmillaria mellea complex and basidiomes ofRhodophyllus abortivus, developing on the same decaying stumps or stems of forest trees, were collected in three forests in Hokkaido. Normal basidiomes ofR. abortivus were found near to, but free from, the rhizomorphs and/or basidiomes ofArmillaria, while abnormal basidiomes, as carpophoroid forms, were developed on the rhizomorphs ofArmillaria. Of three mycoparasiticArmillaria isolates found withR. abortivus, one was identified asA. gallica and two asA. jezoensis. The isolates ofR. abortivus showed excellent mycelial growth and rhizomorph formation on PDA. However, on MDA, RMDA and BMDA, they showed poor aerial mycelia growth and no rhizomorphs. In the contrapositional cultures, the growth ofA. gallica was completely inhibited byR. abortivus on PDA but only slightly inhibited on MDA and RMDA. On the other hand, mutual inhibition at a distance was observed on BMDA. The mycelial growth and rhizomorph formation inA. jezoensis were severely inhibited by the colony ofR. abortivus on PDA, but only slightly inhibited on MDA. On RMDA and BMDA, the colonies of twoArmillaria species andR. abortivus showed mutual inhibition at a distance and apparent rhizomorph formation by bothArmillaria species.     

Underestimated spider diversity in a temperate beech forest

We used canopy fogging to study the high (20–26 m), intermediate (13–19 m) and low (5–6 m) strata in three European beech patches (Fagus sylvatica) in nine months (2005–2007) and estimate species richness and diversity of arboreal spiders. Eight species (10%) were previously unseen in European beech trees, and one of these is likely a new species. Moreover, two species are on the Bavarian red list. Our results revealed that the high stratum of the old-growth trees provided unique resources and possessed the greatest diversity and evenness, whereas intermediate and low strata had high similarity in respect to diversity, dominance, species, and family composition. Since the majority of beech forests consists of mature and young trees in Central Europe, and old-growth forests are rarely preserved, we recommend young beech be used in a sampling protocol for rapid biodiversity assessment. However, adding samples from the two higher strata to the lowest stratum (55 species), almost doubled the estimated species richness (102 species). This suggests that the lower stratum alone does not represent a true image of the total canopy fauna inventory in this, and likely other, beech stands. To complete this comprehensive inventory in European beeches, the Chao1 predicted that additional sampling would be needed in the highest stratum, where there is a high probability to find previously undetected species in a next survey. Our study clearly shows that neglecting the crowns of the largest, tallest trees risks underestimating the overall spider diversity in Central European forests.     

Ectomycorrhizal fungal communities associated with Pinus thunbergii in the eastern coastal pine forests of Korea

We investigated the ectomycorrhizal (ECM) fungal colonization status of Pinus thunbergii mature trees and regenerating seedlings varying in age in coastal pine forests on the east coast of Korea. We established one 20 × 20-m plot at each of two study sites at P. thunbergii coastal forests in Samcheok. Fifty soil blocks (5 × 5 × 15 cm) were sampled at regular intervals, and ten P. thunbergii seedlings of age 0, 1–3, 3–5, and 5–10 years were sampled in each study plot. In total of 27 ECM fungal taxa, Cenococcum geophilum was dominant, followed by Russula sp., Sebacina sp., and unidentified Cortinuris sp. in mature trees. In 0-year-old seedlings, some fungal species such as Sebacina sp., C. geophilum, and unidentified Cortinarius sp. were dominant whereas only C. geophilum was dominant after 1 year, and there were no apparent succession patterns in ECM fungal compositions beyond a host age of 1 year. Most ECM fungal taxa that had colonized seedlings of each age class were also observed in roots of mature trees in each site. These taxa accounted for 86.7–100% and 96.4–98.4% of ECM abundance in seedlings and mature trees, respectively. The results indicate that the species composition of ECM fungal taxa colonizing seedlings of different age in forests is similar to that of surrounding mature trees. Our results also showed that C. geophilum is a common and dominant ECM fungus in P. thunbergii coastal forests and might play a significant role in their regeneration.     

Comparison of structure,regeneration and dead wood in virgin forest remnant and managed forest on Grmeč Mountain in Western Bosnia

This paper compares the forest structure, regeneration and distribution of dead wood in a virgin forest remnant and a close-to-nature managed beech–conifer mixture situated on Grme? Mountain in Western Bosnia. The investigations were carried out in a 1 ha permanent sample plot and 35 circular plots (20 m radius) in the virgin forest and in 17 circular plots (25 m radius) in managed forests. The number of trees in the managed forest was significantly (p = 0.05) higher than that in virgin forest and the distribution of the number of trees per diameter classes had a decreasing trend, but with a different shape in the virgin forest compared to the managed stands. In the lower diameter classes, the stock volume recorded in virgin forest was half of that in the managed forest, whilst for higher diameter classes the cumulated volume of the growing stock was almost double in virgin forest. The young crops had a significantly lower presence in the virgin forest and a larger volume of dead wood was identified in the virgin forest than in managed stands. The study results are important in assessing the consequences of close-to-nature management on the forest structure and regeneration when compared to the condition in virgin forests.     

Distribution of Boros schneideri (Panzer, 1796) (Coleoptera, Boridae) in Lithuania

The distribution of the endangered species Boros schneideri was studied by checking the presence of larvae and adults under the bark of dead Pinus sylvestris trees in 13 pine forests in Lithuania. B. schneideri was found in 10 biggest pine forests, the area of which exceeded 20,000 ha. However, it was not detected in smaller isolated forests. In Kazlų Rūda, Šimonys, Pabradė and Rūdiškės forests this species was recorded for the first time. The part of localities in which B. schneideri was found and the percentage of trees with B. schneideri were significantly higher in the main parts of the biggest forests than in satellite or smaller forests. Both these parameters were significantly lower in forests located in the close vicinity of urban territories than in forests further from them. Consequently, the forest size and the distance of the forest from urban territories were found to be of critical importance for the survival and density of the B. schneideri population. These distribution regularities are important for the establishment of protected areas for this species conservation.     

Short-distance pollen dispersal and high self-pollination in a bat-pollinated neotropical tree

We investigated pollen dispersal and breeding structure in the tropical tree species Caryocar brasiliense Camb. (Caryocaraceae), using genetic data from ten microsatellite loci. All adult trees (101) within a patch of 8.3 ha were sampled, and from these adults 18 open-pollinated maternal progeny arrays were analyzed (280 seeds from 265 fruits). Most fruits presented only one seed (median equal to 1.000) and mean number of ripened seeds per fruit was 1.053 (SD = 0.828). Our results showed that C. brasiliense presents a mixed-mating system, with 11.4% of self-pollination, multilocus outcrossing rate of t _m = 0.891 ± 0.025, and high probability of full-sibship within progeny arrays (r _p = 0.135 ± 0.032). Outcrossing rate and self-pollination varied significantly among mother trees. We could detect a maximum pollen dispersal distance of ∼500 m and a mean pollen dispersal distance of ∼132 m. However, most pollination events (80%) occurred at distances less than 200 m. Our results also indicated that pollen dispersal is restricted to a neighborhood of 5.4 ha with rare events of immigration (∼1% N _e m = 0.35). C. brasiliense also presents a significant but weak spatial genetic structure (Sp = 0.0116), and extension of pollen dispersal distance was greater than seed dispersal (N _b = 86.20 m). These results are most likely due to the foraging behavior of pollinators that may have limited flight range. The highly within-population synchronous flowering, high population density, and clumped distribution reinforce pollinator behavior and affect residence time leading to a short-distance pollen dispersal.     

Vertical stratification and effects of crown damage on maximum tree height in mixed conifer–broadleaf forests of Yakushima Island,southern Japan

We investigated vertical stratification and effects of crown damage on maximum tree height in two mixed conifer–broadleaf forests in Yakushima Island, southern Japan. In both research plots, the conifer trees dominated the upper canopy while the broadleaved trees dominated the middle to lower canopy. Most broadleaved trees were shorter than the median crown-base height (H _CB) of the conifer trees. Estimates of the maximum height (H _max) of the conifer trees were greater than those of the broadleaved trees. Crown damage had significant negative effects on maximum height of the conifer trees. Crown damage was observed for 72.8–88.7% of the conifer trees, and severe types of damage such as stem breakage and top die-back were the most predominant. The H _max of the damaged conifer trees was 16–17% shorter than that of the intact trees and as much as 16–28% shorter than the potential maximum height estimated from the diameter–height relationship of the tallest intact trees. We inferred that crown disturbance is an important factor determining the maximum height of the canopy of the two mixed forests. Our results suggested that vertical stratification between conifer and broadleaved trees may be an important mechanism contributing to their coexistence and additive basal area of mixed forests on Yakushima Island.     

Impact of a strong typhoon on the structure and dynamics of an old-growth beech (<Emphasis Type="Italic">Fagus crenata</Emphasis>) forest,southwestern Japan

Typhoon no. 19 of 1991 (T9119) caused multiple treefalls and created large openings in an old-growth beech (Fagus crenata) forest at Mt. Daisen, in the Daisen Forest Reserve, southwestern Japan. The area of the largest opening was about 1.7 ha (300 m by 70 m). To predict the dynamics of the beech stand after the disturbance of T9119, we investigated the damage to the stand and the density and growth rate of trees with DBH=5–10 cm in a 1-ha plot covering a large part of the largest opening and the adjacent closed canopy. The beech did not regenerate immediately. The regeneration and growth rate of trees with DBH=5–10 cm were related to the frequency of the typhoon attack for at least the past century. In beech forests, small gap formation is the prevailing mode of disturbance. Our results indicate that typhoons affect the structure and dynamics of this beech stand. We suggest that both small gap formation and large-scale disturbance are important for the maintenance of beech forest in some areas.     

黑龙江省蜜环菌生物种的地理分布概况

自1999年至2002年间对黑龙江省境内几个主要林区中的蜜环菌生物种进行了调查、采集和鉴定,并对其寄主种类和子实体发生规律以及地理分布特点进行了总结分析。结果表明:黑龙江省境内至少存在5个蜜环菌生物种,即芥黄蜜环菌Armillaria sinapina,高卢蜜环菌A.gallica,黄盖蜜环菌A.luteopileata,奥氏蜜环菌A.ostoyae和中国生物种F;寄主包括10个针叶和阔叶树种;与其他几种蜜环菌生物种相比较,A.gallica是黑龙江省境内出现概率最大的一个生物种;根据采集经验发现,温度和湿度是影响子实体发生的主要因子。     

Vertical distribution of epiphytic bryophytes and lichens emphasizes the importance of old beeches in conservation

During storms in 2005, a number of beech trees fell over at Biskopstorp, SW Sweden, offering the opportunity to study epiphytes along entire stems. In total 16 beech trees in four beech stands representing three different age classes were included. For each tree, 2 m segments from the base to the top were surveyed. In total 115 species were found (76 lichens, 39 bryophytes), of which 30 were considered to be of conservation concern (22 lichens, 8 bryophytes). For lichens significantly more species were recorded above 2 m in height, whereas more bryophytes were recorded below 2 m in height. Certain red-listed lichens were recorded only above 2 m in height on old trees. In a second data set from the same area 140 age-determined beech trees were surveyed for species of conservation concern at the heights 0–2 and 2–5 m, respectively. These species were found almost exclusively on old beech trees, and presence at 2–5 m was recorded, with one exception, only on those trees which also had species of conservation concern at 0–2 m. Records of these species correlated significantly to microhabitat variables, i.e. the presence of rough bark and moss cover higher up the stems on the old trees. This study indicates that surveying only the base in really old beech forests can underestimate both the number of species of conservation concern and their population sizes. However, surveys restricted to the base in rather even-aged beech stands catch a large proportion of the trees with species of conservation concern.     

Population dynamics of the beech caterpillar, <Emphasis Type="Italic">Syntypistis punctatella</Emphasis>, and biotic and abiotic factors

The beech caterpillar, Syntypistis punctatella (Motschulsky) (Lepidoptera: Notodontidae), often causes extensive defoliation of beech forests in Japan. Outbreaks have often occurred synchronously among different areas at intervals of 8–11 years. Synchrony of outbreaks was considered to be caused by synchrony of weather. Populations of this insect exhibit periodical dynamics in both outbreak and nonoutbreak areas. Factors that might influence the population dynamics of the beech caterpillar were classified from the point of view of the natural bioregulation com-plex, which includes a coleopteran predator, Calosoma maximowiczi, avian predators, parasitoids, entomopathogenic fungi, and delayed induced defensive response (DIR) of beech trees. Because such periodic population dynamics are believed to be caused by one or more delayed density-dependent factors, delayed density-dependent mortality has been identified as a likely source of population cycles. The DIR and pathogenic diseases showed a high order of density dependence. An infectious pathogen, Cordyceps militaris, was considered to be the most plausible agent responsible for periodic dynamics of the beech caterpillar population because insect diseases were effective in cases in which the S. punctatella population started to decrease without reaching outbreak densities, but DIR was not. Conspicuous defoliation caused by this insect tends to occur at certain elevations, where forests are composed of pure stands of beech trees. I propose three different hypotheses to explain this phenomenon: the diversity–stability hypothesis, the resource concentration hypothesis, and the altitudinal soil nutrient hypothesis. Received: November 20, 1999 / Accepted: August 3, 2000     

Leaf Size and Leaf Area Index in <Emphasis Type="Italic">Fagus sylvatica</Emphasis> Forests: Competing Effects of Precipitation,Temperature, and Nitrogen Availability

Plants across diverse biomes tend to produce smaller leaves and a reduced total leaf area when exposed to drought. For mature trees of a single species, however, the leaf area–water supply relationship is not well understood. We tested the paradigm of leaf area reduction upon drought by a transect study with 14 mature Fagus sylvatica forests along a steep precipitation gradient (970–520 mm y⁻¹) by applying two independent methods of leaf size determination. Contrary to expectation, average leaf size in dry stands (520–550 mm y⁻¹) was about 40% larger and SLA was higher than in moist stands (910–970 mm y⁻¹). As a result of increased leaf sizes, leaf area index significantly increased from the high- to the low-precipitation stands. Multiple regression analyses suggested that average leaf size was primarily controlled by temperature, whereas the influence of soil moisture and soil C/N ratio was low. Summer rainfall of the preceding year was the most significant predictor of total leaf number. We assume that leaf expansion of beech was independent of water supply, because it takes place in May with ample soil water reserves along the entire transect. In contrast, bud formation, which determines total leaf number, occurs in mid-summer, when droughts are severest. We conclude that leaf expansion and stand leaf area of beech along this precipitation gradient are not a simple function of water availability, but are controlled by several abiotic factors including spring temperature and possibly also nitrogen supply, which both tend to increase toward drier sites, thus overlaying any negative effect of water shortage on leaf development.     

Occupancy of red‐naped sapsuckers in a coniferous forest: using LiDAR to understand effects of vegetation structure and disturbance

Red‐naped sapsuckers (Sphyrapicus nuchalis) are functionally important because they create sapwells and cavities that other species use for food and nesting. Red‐naped sapsucker ecology within aspen (Populus tremuloides) has been well studied, but relatively little is known about red‐naped sapsuckers in conifer forests. We used light detection and ranging (LiDAR) data to examine occupancy patterns of red‐naped sapsuckers in a conifer‐dominated system. We surveyed for sapsuckers at 162 sites in northern Idaho, USA, during 2009 and 2010. We used occupancy models and an information‐theoretic approach to model sapsucker occupancy as a function of four LiDAR‐based metrics that characterized vegetation structure and tree harvest, and one non‐LiDAR metric that characterized distance to major roads. We evaluated model support across a range of territory sizes using Akaike's information criterion. Top model support was highest at the 4‐ha extent, which suggested that 4 ha was the most relevant scale describing sapsucker occupancy. Sapsuckers were positively associated with variation of canopy height and harvested area, and negatively associated with shrub and large tree density. These results suggest that harvest regimes and structural diversity of vegetation at moderate extents (e.g., 4 ha) largely influence occurrence of red‐naped sapsuckers in conifer forests. Given the current and projected declines of aspen populations, it will be increasingly important to assess habitat relationships, as well as demographic characteristics, of aspen‐associated species such as red‐naped sapsuckers within conifer‐dominated systems to meet future management and conservation goals.     

Ranging behaviour and socio-biology of Eurasian otters (Lutra lutra) on lowland mesotrophic river systems

We examined the spatial structure and socio-biology of a native wild population of Eurasian otters (Lutra lutra) on mesotrophic rivers in a mild temperate climate. Radio-tracking of 20 individuals revealed exclusive intra-sexual adult home-ranges. Adult female home-ranges (7.5 km, SD = 1.5 km, n = 7) were inversely related to river width (, F ₆ = 13.5, P = 0.014) and so appeared to be based on food resources. The aquatic area within adult male home-ranges (30.2 ha, SD = 9.5 ha, n = 5) was greater than that within adult female’s (16.8 ha, SD = 7.0 ha) (t ₁₀ = 2.437, P = 0.035), though this result is inconclusive because some males were tracked on oligotrophic rivers. One adult male expanded its range from 10.2 km to 19.3 km within 5 days of the death of the neighbouring male, suggesting that male home-ranges were heavily influenced by conspecifics.     

Candy Barrel Cactus (<Emphasis Type="Italic">Echinocactus platyacanthus</Emphasis> Link &; Otto: A Traditional Plant Resource in Mexico Subject to Uncontrolled Extraction and Browsing

Candy Barrel Cactus ( Echinocactus platyacanthus Link & Otto [C Mex.]): A Traditional Plant Resource in Mexico Subject to Uncontrolled Extraction and Browsing. The candy barrel cactus (Echinocactus platyacanthus) is an endemic of the Chihuahuan Desert in México that is used as an ornamental plant, for fodder, and for human consumption. The uncontrolled use of this species has resulted in its being put under special legal protection. Although now illegal to harvest, many candy barrel cacti continue being destroyed in situ by both gathering and livestock grazing. This study describes the uses of this species and the characteristics of its natural population in central Mexico. In order to estimate density, percentage of damaged cactus, and height of candy barrel cactus, censuses were carried in stands of 2,500 m². The anthropogenic disturbance in each site was estimated by an environmental disturbance index (DI). Results show that the state of Hidalgo has the best conserved population (mean density = 1,111 ind/ha, stratus height = 137 cm, and only 2% of the total cacti injured). Populations in Puebla represent an intermediate state of conservation, while Querétaro has populations with the lowest density (435 ind/ha), the shorter height (62 cm), the highest foraging (18%), and the greatest DI (71.30). We recommend that conservation strategies for this species be implemented immediately, and that areas be established that exclude livestock and prevent extraction by humans.