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A graduate seminar to select the 5 most important papers pub lished in the first 50 years of the Journal of Range Management (J R M), 1948‐1997, cultivated an appreciation for the development of the discipline of rangeland science and management, and provided some historical perspective to judge the JRM. A review of textbooks, and papers describing early milestones and the use of citation counting were helpful in developing criteria to discriminate the importance of papers. The greatest disagreement among the 9 participants focused on the use of citation counts as a criterion: 2 students used only counts and 3 students refused to use counts. Eighteen papers received at least 1 vote as a top 5 paper, and 2 plant succession-vegetation monitoring papers were clearly the most popular. The exercise revealed that discontent with the JRM is not new. Although the JRM now covers a wider variety of topics, including both reductionist and synthetic works, some students felt that it was less encompassing of multi ple values of rangelands and the breadth of rangeland science than recent texts. The students found that the selection of impor tant papers expanded their understanding of the discipline and their resolve to publish in the JRM. Ideally, others will be chal lenged to perform this review for the benefit of students, the dis cipline, and the JRM.

This paper offers a review and reassessment of the biogeography of the Afromontane region. Much of the montane vegetation of Africa, especially in the southern part of its distribution (the southern Afromontane region) is characterized by a mosaic of forest 'islands' in a 'sea' of grassland, with or without heathland elements. Controversy has arisen as to the origin of these grasslands and the view has emerged, based on a variety of phytogeographical, zoogeographical, ecological, pedological and historical evi- dence, that the grassland element has been derived, or at least markedly extended, in the recent past by forest clear- ance through human agency. An alternative hypothesis holds that the grassland is a much older component of the Afromontane landscape. The paper assesses these two op- posing viewpoints in the light of published palaeoecological and biogeographical evidence not previ- ously brought to bear on the problem of Afromontane grassland origins in general. The physical environment and vegetation of the southern Afromontane region is reviewed and the suggestions put forward to account for the wide- spread occurrence of grasslands in the region are presented. The competing hypotheses are then tested against data on plant species richness and diversity from a number of upland areas within the region and against published Qua- ternary palynological data from the Nyika Plateau, Malawi, the Inyanga Mountains, Zimbabwe and the Winterberg Escarpment area of South Africa. The resulting reassess- ment offers strong support for the idea that the grasslands have been prominent in the southern Afromontane region since before the permanent occupation of the mountains by people. Environmental changes, especially of the late Qua- ternary, are suggested as having been important in establishing the vegetation pattern and, while increased magnitude of human impact in recent times is apparent, the so-called 'relict' nature of montane forest patches is ques- tionable. It is argued that the southern Afromontane grasslands are themselves relict from a time, around the last glacial maximum, when the climatic conditions were more suited to these formations than to forest.

Particularly since India's Independence, concern about forest decline and opposition by forest-dependent populations to a perceived neglect and exploitation of local forests by the Forest Department has resulted, in certain areas, in the establishment of community-based forest protection committees. In Bihar, attempts to overcome the antagonistic Forest Department relations that prevailed during much of the 1980s, plus a recognition of the need to involve local people more in forest management and protection, have resulted in the establishment of the Bihar joint forest management programme. This aims to follow the example set by autonomous forest protection committees by setting up 'village protection and management committees' in degraded Protected forest areas. This paper, which stems from my doctoral fieldwork in the Jharkhand region of Bihar, will examine the issue of forest protection in light of three main issues. A first issue concerns the extent to which a strong historical sense of place and (particularly tribal) identity can be effective in mobilising an interest in and concern for local resource management and protection. A second issue concerns the degree to which traditional, charismatic village leaders are important in overcoming intra-village tensions over resource use and promoting successful forms of community action. A third issue concerns the extent to which the above two factors are likely to be important in the success of 'official' forest protection and management committees.

To be adequate, evenness indices must satisfy three criteria: (1) independence of species richness; (2) independence of sample size; and (3) unambiguous relationship to evenness. I examine Bulla's evenness index in the light of these criteria, logically implying a failure to satisfy the first, and experimentally proving failures to satisfy the second and third. Therefore, this index is inadequate. I also examine Bulla's heterogeneity index. Being based on his evenness measure, it is also inadequate. Moreover, the index is not the correct heterogeneity measure under his own approach. I derive the correct index and demonstrate its kinship to the evenness index. Even this correct heterogeneity measure lacks a future because no adequate diversity indices can be obtained from Bulla's overlap. By re-examining the savanna data with which Bulla attempted to show the superiority of his index, 1 prove his analysis to be an artifact. In response to Bulla's criticism on G 2,1 , I demonstrate that his argumentation is wrong, and reassure that G 2,1 is an adequate evenness index. To conclude, I offer three general considerations on index testing that, if followed, will prevent a repetition of Bulla's errors.

It is hypothesized that the principal features of higher plant distributions at continental scales are determined by the macroclimate. Bioclimate data have been computed on a 50 km grid across Europe. Along with published maps of higher plant distributions based upon the same grid, these data have been used to derive climate response surfaces that model the relationship between a species' distribution and the present climate. Eight species representative of a variety of phytogeographic patterns have been investigated. The results support the hypothesis that the European distributions of all eight species are principally determined by macroclimate and illustrate the nature of the climatic constraints upon each species. Simulated future distributions in equilibrium with 2 x CO 2 climate scenarios derived from two alternative GCMs show that all of the species are likely to experience major shifts in their potential range if such climatic changes take place. Some species may suffer substantial range and population reductions and others may face the threat of extinction. The rate of the forecast climate changes is such that few, if any, species may be able to maintain their ranges in equilibrium with the changing climate. In consequence, the transient impacts upon ecosystems will be varied but often may lead to a period of dominance by opportunist, early-successional species. Our simulations of potential ranges take no account of such factors as photoperiod or the direct effects of CO2, both of which may substantially alter the realized future equilibrium.

Freshwater investigations in Greenland yielded four gards homothermic springs and their surroundings it is sug- species perhaps endemic to the island. These are reported gested that the freshwater's heating capacity (thermal along with thirteen other 'endemic' species found in the insulation) may have resulted in trimming rather than extinc- literature, most of which turned out to be aquatic or semi- tion of faunas. This may explain the southern character of the aquatic lowland species. The significance of these as possible 'endemic' species, however also the apparent ones in homoth- markers of a fauna unique to Greenland (beyond the unique- ermic springs. The faunas of Greenland may represent an early ness primarily resulted from immigration/emigration history stage in endemization, and it is concluded that for operational (species composition)) is commented on. Greenland probably reasons Greenland can be called a zoogeographical unit of its lost most of its biota during the last glaciation, except perhaps own. in the south, but in southern Greenland the glacial survivors (from preglacial communities) ought to appear in mountainous Key words. Greenland, freshwater habitats, invertebrates, and cold-eurythermous places. With some reservation as re- endemism.

Thespatialeomponent ofherbivory remainsenigmatic although it is a central aspect of domestic and native ungulate ecosystems. The effects of ungulate movement on plants have not been clearly established in either range or wildlife management. While livestock movement systems have been implemented to cope with increases in livestock density, restrictions on movement, and overgrazing, B large number of studies have disputed the effectiveness of different livestock movement patterns. Traditional pastoralism, particularly nomndism, has been perceived as irrational and even destructive, hut many studies have documented features of traditional pastoral land use that would promote sustainability. Disruptions of wild ungulate movements have been blamed for wildlife owrgrazing and population declines, but actual patterns and mechanisms of disrupted movement and population responses have been poorly documented. Models that integrate plant growth, ungulate movement, and foraging are suggested as a way to improve analyses of spatial plant-herbivore systems. Models must give due attention to nonforage constraints on herbivore distribution, such as topography. Models should assess the significnnee of movement 8s a mans Of coping with local climatic variation (patchy rainfall). Models that distribute an aggregate population over a landscape in relation to the distribution of habitat features deemphasize aspects of ungulate movements and population responses that inevitably cause nonideal distributions, particularly in natural ecosystems. Individual based models describe movement and foraging processes more accurately, hut these models are difficult to apply over large areas. Both top-down and bottom-up approaches to spatial herbiwry are needed. To model plant responses to movement, it is important to account for small scale phenomena such as tiller defoliation patterns, patch grazing, and grazing lawns as well as large scale patterns such as rotation and migration. Herbivory patterns at these difTerent scales are interrelated. Managers of wildlife and domestic livestock populations confront similar problems as they attempt to interpret ungulate spatial distribution patterns and their effects on plants. Overgrazing and subsequentecosystemdegradation onrangelandsorpastoralgrazing areas arc often attributed to inappropriate management of livestock spatial distributions. Overabundances of ungulates in wildlife preserves, and consequent overgrazing, arc often attributed to human interference with natural ungulate migrations or dispersal patterns. These management problems are analogous in that ungulate spatial utilization patterns determine how grazing impacts are distributed in space and in time. Ecosystem sustainability is affected by interactions among animal movement and abundance, plant growth, plant response to grazing, and the physical structure of the landscape. The consequences of herbivory for ecosystems depend, of course, upon herbivore abundance. However, herbivore abundance is expressed in terms of numbers of animals per unit of land, per unit of plant production, or per unit of land per unit time. These measures have been distinguished as stocking density, grazing pressure, and stocking rate, respectively (Heitschmidt and Taylor 1991). Until recently, research and management of ungulate herbivores have treated the denominators of these expressions as homogeneous. The aim of this paper is to explore heterogeneities in these denominators that are normally averaged out.

Pollen, molluscan, and sedimentological analyses have been undertaken from a tufa, which forms part of a near-complete Post-glacial succession from Sidlings Copse near Oxford. Local pollen and mollusc zones are defined and the times of arrival of critical species compared. It is shown that some pollen and mollusc zone boundaries coincide pre- cisely but that others do not, with some faunal changes occurring during periods of vegetational stability. A detailed chronology is provided by radiocarbon dating using acceler- ator mass spectrometry. Tufa formation began at about 9300 yr BP as hazel (Corylus avellana) woodland began to fill the previously open land- scape. An unshaded marsh initially developed on the surface of the tufa, which supported snails such as Vertigo angustior and Discus ruderatus (a boreo-alpine species now extinct in Britain). Hazel woodland gradually encroached and caused the replacement of the early marsh communities by woodland mollusc assemblages. Discus ruderatus was replaced by D. rotundatus at 8990 ? 90 yr BP, and subsequently Leiostyla anglica and then Spermodea lamellata appeared. At 7180 ? 85 yr BP lime (Tilia cordata), slightly preceded by alder (Alnus glutinosa), spread into the area. Oxychilus cellar- ius first appeared at this time. Lime and elm (Ulmus) declined at 5250 t 75 yr BP, and this was accompanied by changes in the molluscan fauna and vegetation suggesting a reduction of shading. The land snail fauna at this time was composed of an unusual assemblage dominated by Leiostyla anglica and Oxychilus cellarius. Tufa formation ceased shortly after 5065 ? 120 yr BP, perhaps due to hydrological changes initiated by human activity. Rates of tufa growth from 1.3 to 5.4 cm/100 years have been calculated from the radiocarbon dates. These accumulation rates are similar to those derived from the overlying organic sediments. The upper sediments are highly organic and contain very few molluscs, but pollen continues to occur, enabling reconstruction of vegetational history up to the present. The biostratigraphy of Sidlings Copse is compared with neighbouring sites and other sequences from British tufas.

The environmental relations of rainforest struc- tural and physiognomic characteristics (in the Wet Tropics of Queensland, Australia) were quantified using the Monomax algorithms. The probabilities of occurrence for these characteristics were predicted in relation to indices of soil parent material and long-term mean monthly climate estimated at the point of survey for a set of 256 sites. A relatively small number of indices proved the best predic- tors (minimum temperature of coldest month; maximum temperature of hottest month; precipitation seasonality; precipitation of driest quarter; nutrient supply index). Spatial predictions of potential distributions were generat- ed by coupling the predictive functions to gridded esti- mates of the indices used as independent variables. Landsat MSS data were used to restrict the analysis to forested land. Numerical classification and ordination tech- niques were also employed to gain further insight into the spatial relationships. The assumptions of monotonicity required by the Monomax algorithms drew upon hypothe- ses of plant-environmental relations. The results supported the notion that as long as moisture is not limiting, the like- lihood of both larger leaf size and complex structure increases with increasing values of temperature and nutri- ent supply. The potential distributions of structural types were suggested as useful biological units for ecological comparison and conservation evaluation.

A global vegetation model based on the climato- logical approach of Budyko is developed. The major vege- tation zones of the world are predicted by a two- dimensional ordination of a Dryness Index and Potential Evaporation, which is derived from radiation balance. Mean temperature of the warmest month is also used to separate the Ice/Polar Desert, Tundra, and Taiga zones. Pre- dictions of vegetation distributions are made using a global climate database interpolated to a 0.5? by 0.5? terrestrial grid. The overall impression from examining the resulting global vegetation map is that the modified Budyko model predicts the location and distribution of the world's vegeta- tion fairly well. Comparison between model predictions and Olson's actual vegetation map were based on Kappa statistics and indicate good agreement for Ice/Polar Desert, Tundra, Taiga, and Desert (even though we predict too much Desert). Agreement with Olson's map was fair for predicting the specific location of Tropical Rain Forest and Tropical Savannas, and was good for predicting their general location at a larger scale. Agreement between Olson's map and model predictions were poor for Steppe, Temperate Forest, Tropical Seasonal Forest, and Xerophy- tic Shrubs, although the predictions for Temperate Forest and Tropical Seasonal Forest improved to fair at a larger scale for judging agreement. Agreement with the baseline map of Olson was poor for Steppe and Xerophytic Shrubs at all scales of comparison. Based on Kappa statistics, overall agreement between model predictions and Olson's map is between fair and good, depending on the scale of comparison. The model performed well in comparison to other global vegetation models. Apparently the calculation of radiation balance and the resulting Dryness Index and Potential Evaporation provides important information for predicting the distribution of the major vegetation zones of the world.

Debate on the origin and dispersal of Cocos nu- cifera has generally concluded that the palm has a South- east Asia-Melanesian origin. The means of dispersal to the margins of its pre-industrial range is in more dispute. The literature on this question is reviewed. A stochastic simula- tion model of the winds, currents and islands of the Pacific Ocean tests the hypothesis of trans-Pacific drift dispersal. The model suggests that the probability of coconuts drifting unaided to the west coast of Panama while remaining viable is extremely low. Dispersal to Panama by humans seems more likely.

The range science profession has traditionally relied upon the concept of apical dominance to explain tiller initiation in perennial grasses. The physiological mechanism of apical dominance is assumed to follow the direct hypothesis of auxin action, which was originally proposed during the 1930's. This hypothesis indicates that the plant hormone auxin (IAA), produced in the apical meristem and young leaves, directly inhibits axillary bud growth. The direct hypothesis was, and continues to be, the sole interpretation of the physiological mechanism of apical dominance since the concept was initially adopted by the range science profession. However, the direct hypothesis was abandoned by plant physiologists during the 1950's because of experimental and interpretive inconsistencies and the demonstrated involvement of a second hormone, cytokinin, in apical dominance. The cytokinin deficiency hypothesis has replaced the direct hypothesis as the current hormonally based interpretation of apical dominance. This hypothesis indicates that IAA produced in the apical meristem blocks the synthesis or utilization of cytokinin within axillary buds inhibiting their growth. Despite wide acceptance, numerous issues remain unresolved concerning this hypothesis, suggesting that it may also be an incomplete interpretation of the physiological mechanism of apical dominance.

WILSON, L. D., AND L. PORRAS. 1983. The ecological impact of man on the south Florida herpetofauna. Univ. Kansas, Mus. Nat. Hist., Lawrence. WINGATE, D. B. 1965. Terrestrial herpetofauna of Bermuda. Herpetologica 21:202-218. MUSEUM OF VERTEBRATE ZOOLOGY, UNIVERSITY OF CALIFORNIA, BERKELEY, CALIFORNIA 94720. PRESENT ADDRESS: CENTER FOR POPULATION BIOLOGY, 2320 STORER HALL, UNIVERSITY OF CALIFORNIA, DAVIS, CALIFORNIA 95616. Accepted 27 Oct. 1991.

A model to predict global patterns in vegetation physiognomy was developed from physiological considera- tions influencing the distributions of different functional types of plant. Primary driving variables are mean coldest- month temperature, annual accumulated temeprature over 5"C, and a drought index incorporating the seasonality of precipitation and the available water capacity of the soil. The model predicts which plant types can occur in a given environment, and selects the potentially dominant types from among them. Biomes arise as combinations of domi- nant types. Global environmental data were supplied as monthly means of temperature, precipitation and sunshine (interpolated to a global 0.5" grid, with a lapse-rate correc

Inhibitory effects of metabolites from balsam poplar (Pops Unpublished data, P.B. Reichardt) and the relative amounts present in juvenile and mature plants and plant parts are being quantified. In addition, bioassays are being conducted to evaluate deterrent properties of different resin fractions isolated (Bryant and Kuropat 1980, Bryant 1981, Bryant et al. 1983, Unpublished data, P.B. Reichardt). Bryant and Kuropat (1980) speculated that current annual growth (CAG) twigs ofjuvenile Alaska paper birch are less digestible than CAG twigs from mature-growth-form plants due to their higher resin content, which may be toxic to rumen microbes. Previous studies have demonstrated antibacterial effects or inhibition of digestion by rumen microbes exposed to various terpenoids. Nagy et al. (1964) found that essential oils in sagebrush (Artemisia tridentata) inhibited bacterial growth and decreased gas and volatile fatty acid production in rumen of mule deer (Odocoileus hemionus). Oh et al. (1967) and Longhurst et al. (1968) found that oxygenated monoterpenes present in Douglas fir (Psuedotsuga menziesii) needles strongly inhibited Columbian black-tailed deer (0.h.’ columbianus) rumen microbial activity. Schwartz et al. (1980) reported that volatile oils present in various junipers (Juniperus spp.) reduced cellulose digestion in vitro by up to 40%. In this paper, we present evidence that benzyl alcohol, cineok papyrifcric acid, and a steam distillate fraction from juvenile Alaska paper birch depress in vitro fermentation of cellulose SUSpended in rumen fluid from wapiti (Cervus elaphus nelsoni). Material and Methods Four resin components, 2 each from balsam poplar and paper Authorsare research assistant, Department of Biological Sciences, MichiganTechnological University, Houghton 49931; research assistants, Department of Animal Sciences, University of Alberta, Edmonton T6G 2P5. The authors thank the following persons for their support and assistance with various aspects of this study: J. Bryant, P. Reichardt, R. Hudson, L. Jebson, D. Renecker, J. Aalhus, D. Summers, and T. Fenton. Financial support for this study was prowded by Michigan Technological University and the University of Alberta. Manuscript accepted October 15, 1984. 370 birch, were chosen for testing because of their ability to deter browsing by snowshoe hare (Lepus americanus) (Unpublished data, J.P. Bryant). Papyriferic acid, a triterpene carboxylic acid, and a steam distillate fraction, composed primarily of sesquiterpenes, from juvenile Alaska paper birch were provided by Dr. P.B. Reichardt (Department of Chemistry, University of Alaska, Fairbanks). Papyriferic acid was isolated from diethyl ether extract of CAG twigs from winterdormant juvenile plants by column chromatography. The steam distillable fraction of juvenile paper birch was isolated by diethyl ether extraction of the steam distillate (Personal communication, P. Reichardt). In addition, cineole (an isoprenoid) and benzyl alcohol, 2 compounds present in balsam poplar bud resin, were obtained commercially (Sigma Corp., St. Louis, MO.). Sample Preparation Concentrations of resin fractions used for in vitro trials were based on the amount of each resin component available and on the amount estimated to be present in CAG twigs from both mature and juvenile forms of paper birch and balsam poplar (Unpublished data, P.B. Reichardt). Because of the limited availability of papyriferic acid and paper birch steam distillate, treatment concentrations for these compounds were 5 and 20 mg per gram of substrate. Cineole and benzyl alcohol were tested at concentrations of 5, 10, 20,40, and 100 mg per gram of substrate. All treatment concentrations were prepared on a dry weight basis. Commercial purified cellulose (“Alpha floe”, Lee Chemicals Ltd., Toronto, Ont.) was used as a substrate. Resin components were dissolved in excess acetone, placed into a 150-ml round-bottom flask with the cellulose substrate, and swirled until the material was saturated. The flask was then placed on a vacuum rotodistiller with a water bath temperature of 50°C for approximately 10 minutes, or until the acetone had evaporated. The treated cellulose was removed from the flask, placed into metal dishes, and oven-dried at 4O“C for 48 hours. Following drying, samples were mixed in a micro mill and stored in sealed glass containers. In Vitro Techniques The in vitro techniques used to measure digestion of dry matter were developed by Tilley and Terry (1963) and modified by Morgantini and Hudson (in press). Rumen inoculum was obtained from a fistulated wapiti steer which was maintained on pelleted aspen concentrate, alfalfa hay, freshly cut browse, and fresh grass available ad libitum in a l-ha pasture. Triplicate samples were tested at each concentration level. Acetone controls were also tested for antimicrobial effects. Differences were tested by one-way analysis of variance and Duncan’s new multiple range test (KO.05).

Leaf litter breakdown, a critical ecosystem level process in streams and other aquatic environments , has been conceptualized using models borrowed from terrestrial systems. We argue that current views of the process in fresh waters need to be conceptually improved. Specifically, we think the idea that breakdown proceeds in three distinct temporal stages (leaching, conditioning, fragmentation) has been over emphasized. Leaching, the massive loss of soluble leaf components within 24 h after immersion, is generally considered to constitute a well-defined first stage. Recent evidence suggests, however, that the initial solute losses are largely an effect of the un natural drying procedures to which experimental leaves are normally subjected. Fresh leaf litter does lose solutes when immersed,but gradually throughout the breakdown process rather than instantly upon wetting. Conditioning, the second breakdown stage, describes the enhancement of leaf palatability for detritivores by microbial colonization, and is thus ultimately targeted towards a group of organisms (which contribute to litter degradation) rather than addressing the breakdown process per se. Furthermore,conditioning implies a key role for detritivorous invertebrates and underrates the established direct degradative activity of microbial decomposers. If, thus, leaching and conditioning are not generally useful operators to describe portions of the litter breakdown process in freshwaters, the traditional concept, which emphasises leaching, conditioning and fragmentation as three sequential stages, loses much of its appeal. Consequently, we propose a new conceptual model, in which the coincidence and interplay of various subprocesses of litter breakdown is more strongly recognized. In this model, we propose to view the process in terms of the products of litter breakdown-as a complement to the usual perspective which focuses on litter mass loss. Six primary breakdown products are considered : bacterial, fungal and shredder biomass; dissolved organic matter; fine-particulate organic matter; and inorganic mineralization products such as CO2, NH+ and PO3-. We present a scheme illustrating the hypothesized formation of these products throughout breakdown. However, to improve understanding of the process, application of the proposed conceptual framework in experimental work is necessary.

Calyptranthes dryadica, a new species of Myrtaceae from the coastal forests of Sao Paulo, characterized by few-flowered panicles with large buds, is described and illustrated. The botanically little known coastal forests of Brazil are one of the most threatened ecosystems in the world. Floristic studies in the Ecological Reserve of Jurdia-Itatins, in the southern coastal forests of the state of Sao Paulo, have shown that the Myrtaceae are the dominant family in number of species, one of which is here recognized as new to

Since its emergence in the mid19th century, the Darwinian theory of evolution has had a significant and far-reaching impact on the life sciences. Within the discipline of psychology in particular, evolutionary theory has transformed the approach to many traditional issues, such as the nature and function of social behavior (cf. Hinde [14]). Curiously, however, it has had only a limited influence on the psychological study of perception. In this paperwe shall examine the standard approach to visual perception in light of evolutionary theory. We shall then contrast this perceptual theory with an alternative, proposed by James J. Gibson, which we find to be more thoroughly grounded in an evolutionary point of view. Finally, we shall consider a role which phenomenology can play in developing this ecological or naturalistic approach to perception. Although an increasing number of philosophers and psychologists are becoming acquainted with the ecological approach to perception, many more remain unaware of the possibilities which it offers. In this context, we have chosen to present a relatively general and open-ended "position paper," which raises a number of issues, and so is intended to draw more widespread attention to this important theoretical option.

Age and size data on over 2200 trees were used to reconstruct developmental patterns and regeneration dynamics of four successional and two climax stands of subalpine forests in the Colorado Front Range. The dominant tree species of these forests are Engelmann spruce (Picea engelmannii), subalpine fir (Abies lasiocarpa), limber pine (Pinus flexilis), and lodgepole pine (Pinus contorta). Due to relatively weak relationships between age and size for all four species, patterns of stand development could not have been reliably inferred from size data alone. Following wildfire on the most xeric sites, limber pine is the principal pioneer species and dominates seedling establishment for 50 to 100 or more years. At most sites, however, Engelmann spruce and subalpine fir eventually establish and gradually replace limber pine. On less xeric sites, depending on availability of seed, either Engelmann spruce of lodgepole pine, alone or together, may act as pioneer species. Establishment of subalpine fire may be coincident or may be several decades later. Eventually it and Engelmann spruce replace lodgepole pine as the canopy dominants. The age structures of the stands investigated are consistent with the view that variation in establishment is a least as important as mortality in shaping age frequency distributions in successional stands. in climax Engelmann spruce - subalpine fire stands both species have all-aged populations; the typically greater abundance of young subalpine fir appears to be compensated by the much greater longevity of Engelmann spruce.

Population age structures of old-growth Engelmann spruce, subalpine fir and lodgepole pine are described in the Colorado Front Range subalpine forest (2850 and 3500 m). Among the populations of these three species, five types of age structures can be recognized; up to four different types of age structures were found in one species under different environmental or historical conditions and no species showed the same type of age structure throughout its entire range of occurrence. The age structures of populations are used to infer their climax or successional (selfreplacing or not self-replacing) status. From the combination of climax or successional populations in a stand and the distributions of these combinations on environmental gradients, three types of forest are recognized: (1) climax lodgepole; (2) climax sprucefir, which is pioneered after disturbance by lodgppole; and (3) climax spruce-fir which is pioneered primarily by spruce. The changes from one forest type to another follow a unidimensional gradient which begins with climax lodgepole at low elevation, dry sites, followed by a forest mosaic of successional lodgepole and climax spruce-fir at both higher elevations and intermediate moisture sites, and ends with climax spruce-fir in which lodgepole is not pioneer, at both high elevations and on the most mesic sites. INTRODUCTION Studies of the seral status of species are commonly based on size distributions and differences in sizes between species in a stand. However, significant errors may be introduced into these studies by differences in growth rates between species. In addition, the seral status of a species may not be reflected in its size distribution because of a tendency for gaps in the distribution to be filled by differential growth of individuals (Schmelz and Lindsey, 1965; Johnson and Bell, 1975). The result may be that the shape of the size distribution does not reflect whether a population is reproducing, i.e., successional or climax. Ideally, succession should be studied by observing an area over a period of time. In the case of long-lived species, such as trees, this is not practical. However, the age structures of tree populations may indicate whether they are successional -or climax, and successional pathways may be inferred from this information (Leak, 1975). Climax types and advanced seral sequences were investigated in the Colorado Front Range subalpine forest using tree population age structures of the three dominant species: Engelmann spruce (Picea engelmannii Parry), subalpine fir IAbies lasiocarpa (Hook.) Nutt.] and lodgepole pine (Pinus contorta Engem.) The objectives of this study are: (1) to describe the age structures of Engelmann spruce, subalpine fir and lodgepole pine; and (2) to infer seral and climax status from tree age distributions. The study area was the Fraser Experimental Forest (39?50'N, 105050'W), located 8 km (5 miles) SW of Fraser, Colorado. This area is in the southern part of the W flank of the Colorado Front Range, and was chosen because of its accessibility and undisturbed condition. LITERATURE There has been considerable debate over the boundaries of a subalpine zone in the Colorado Front Range and other nearby portions of the Rocky Mountains (Ramaley, 1907; Young, 1907; Ramaley and Robbins, 1909; Bruderlin, 1911; Present address: Department of Botany, Louisiana State University, Baton Rouge 70803.

Microwave ovens l ppe8r to be 8 vi8blc 8Item8tive to forced 8ir I8bor8tory ovens for obt8ining dry weights for vegetrtion samples. Two gr8ss species, Kentucky bluegr8ss (Pea pratensis) 8nd till fescue (Fatucu urundinaceu), were used to determine percent moisture lose by yeighbt at 3 weight lo8dings. The lo8dings were al 8pproxim8tely 50,100, urd 200 weights. For the 3 loadings, times rquired to obt8in a dried sample were at most 4.5,7.5, and 11.0 minutes, respectively. The time rquired for 8U sunples in the convention81 18b oven WM 72 hours.

This viewpoint paper examines criteria for preparing and evaluating manuscripts that involve stochastic approaches. Increasing use of stochastic mathematics to address inherent uncertainty in natural systems has meant increasing challenges to write and evaluate the manuscripts reporting such research. The paper provides a set of criteria directed at aiding authors, referees and associate editors in writing and evaluating this research. The paper asserts that for research papers to be acceptable to a management science journal such as the Journal of Range Management, they should at least be mathematically appropriate, functionally valid, pragmatically justified, technically comprehensible, and generally readable. It then examines the relationship of the concept of synthesis to the management implications sections of journal articles. The paper advocates increased attention to the concept of synthesis in making papers that report stochastic research in particular, and technical research in general, more understandable to readers, and more useful in range management science.

This paper analyzes the kinds of publications that are currently accepted by the Journal of Range Management, and in view of the evolving identity of range science, proposes a review of the those kinds of papers by the Editorial Board. The paper explores the kinds of papers that would help the Journal in identifying and developing range management science. It suggests a modified emphasis directed at increasing conceptual creativity, and developing explicit, integrative linkages and communications of range management science. In practice, this revision involves increased publication of synthesis papers, and increased emphasis of synthesis in the Journal's publications in general. Major benefits to the Journal would likely be increased diversity of published papers, broader professional diversity of authorship, increased readership, and increased effectiveness in serving and encouraging range management science.

The collections reported in this paper were largely obtained as part of a general mycological investigation of the Azores archipelago undertaken by BMS and G. B. Butterfill (Kew) during two visits to the Islands, in April May 1995 and OctoberNovember 1996. They form part of a larger collection of fungi the study of which is still ongoing. Previous papers based on these collections have treated the Uredinales and Ustilaginales (Spooner & Butterfill 1999c), Myxomycetes (Ing et al. 1999), coprophilous discomycetes (Spooner & Butterfill 1999b), a new genus of coelomycetes (Punithalingam & Spooner 1999), and the heterobasidiomycetes (Roberts & Spooner 2004). In addition to these collections, a small number of fungi collected by P. J. Wanstall from Pico in September 1952 has recently been received at Kew. Several poroid species were included amongst these and are also reported here. The Azores archipelago, situated in the midAtlantic some 1250 km west of the nearest part of Europe, is of tertiary age and comprises nine main islands. These are volcanic in origin and were never connected to any land mass. Since colonisation by European settlers during the 15th century, the wildlife of the Azores has, inevitably, been greatly influenced by human activity. The native flora, especially, has been and continues to be adversely affected in many areas, sometimes severely so, by the naturalisation and spread of exotic species from many parts of the world able to thrive in the mild, humid climate. This has also had an influence on the

BLOOM, THOMAS C.',2, JERRY M. BASKIN1, AND CAROL C. BASKIN1'3 ('Department of Biology, University of Kentucky, Lexington, Kentucky 40506-0225, 21209 Glade Street, College Station, Texas 77840, 3Department of Agronomy, University of Kentucky, Lexington, Kentucky 40546-0091). Ecological Life History of the Facultative Woodland Biennial Arabis laevigata variety laevigattyaaa (Brassicaceae): Effects of Leaf Litter Cover, Herbivory, and Substrate-type on Bolting and Fecundity. J. Torrey Bot. Soc. 130:16-22. 2003.-This paper reports the results of a study on the effects of leaf litter cover, herbivory, and substrate-type on bolting and fecundity in the facultative biennial Arabis laevigata var. laevigata, a species of rocky, deciduous woodlands in eastern North America. Probability of bolting decreased with mean cumulative amount of leaf litter cover and of rosette herbivory and was lower for plants growing on soil than for those growing on rock-moss. With rosette size factored out, both cumulative rosette herbivory and flower stalk herbivory decreased fecundity, whereas neither cumulative leaf litter cover nor substrate-type had an effect on seed production. On the basis of data in the present study and those in five previously-published papers on the life history biology of A. laevigata var. laevigata, we conclude that the taxon exhibits a stress-tolerant ruderal (SR) strategy sensu J. P. Grime's triangular model of plant strategies.

Botanical explorations of heretofore poorly inventoried limestone formations in the northern Vietnamese border province of Ha Giang have yielded a new taxon of conifer that is to be classified in a cupressoid clade of Cupressaceae. It has foliage and ovuliferous cone characters that compare closely to Chamaecyparis nootkatensis (D. Don) Spach, as well as a feature peculiar to it and rare in conifers: the simultaneous occurrence of ju- venile and mature leaves on normal plagiotropic branching systems of mature trees. It is proposed in this paper to unite C. nootkatensis with the newly discovered species in a new genus Xanthocyparis; of this new genus and species a full description and illustrations are provided. Additional contributions to this paper include observations on its habitat, conservation status, and a taxonomic discussion.

Based on field and herbarium work, in this paper 23 species of Quercus are recognized for the State of Mexico. Ten of the species belong to section Quercus and 13 to section Lobatae. Fifteen of the species are endemic to Mexico, seven extend to Central America, and only Quercus rugosa is found north of the Mexican border in the United States. The paper includes a dichotomous key and morphological descriptions for all the taxa, as well as ethnobotanical, phonological, and ecological data.