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This book offers a unique overview on the career and work on Benedict XII, the third pope of Avignon. Benedict XII (ca. 1334-1342) was a key figure of the Avignon papal court, renowned for rooting out heretics and distinguishing himself as a refined theologian. During his reign, he faced the most significant religious and political challenges in the era of the Avignon papacy: theological quarrels, divisions and schisms within the Church, conflicts between European sovereigns, and the growth of Turkish power in the East. In spite of its diminished political influence, the papacy, which had recently moved to France, emerged as an institution committed to the defense and expansion of the Catholic faith in Europe and the East. Benedict made significant contributions to the definition of doctrine, the assessment of pontifical power in Western Europe, and the expansion of Catholicism in the East: in all these different contexts he distinguished himself as a true guardian of orthodoxy.

Jean-Claude Schmitt est médiéviste et directeur d’études à l’École des Hautes études en Sciences Sociales, où il enseigne l’histoire des images et des représentations dans l’Occident médiéval. Parmi ses nombreux ouvrages, nous pouvons citer La raison des gestes dans l’Occident médiéval (Gallimard, 1990), Les Revenants. Les vivants et les morts dans la société médiévale (Gallimard, 1994), Le corps, les rites, les rêves, le temps. Essais d’anthropologie médiévale (Gallimard, 2001), Le Corps des...

Balsam fir (Abies balsames (L.) Mill.) seeds dispersed in autumn–winter can be covered by many layers of broadleaves when they germinate under deciduous trees during the following growing season. Our goal was to test the effect of seed density, broadleaf litter thickness, and substrate type on emergence, morphology, and dry mass allocation of balsam fir. The greenhouse experiment included three seeding densities, four litter thicknesses covering the seeds, and two substrate types. The broadleaf mixture was composed of white birch (Betula payrifera Marsh.), trembling aspen (Populus tremuloides Michx.), and pin cherry (Prunus pensylvanica L.f.) collected on the forest floor of a 30-year-old postfire stand. Seed density had no effect on emergence from under broadleaf litter. Emergence was lower on the litter substrate than on potting soil. Seedling emergence and vigor declined as broadleaf thickness increased. Depending on substrate type, emergence was reduced by 20% (leaf litter substrate) to 28% (potting soil) when seeds were covered by 1.4–2.0 cm of broadleaves. An overtopping layer of 2.5–3.0 cm reduced emergence by 57%. Balsam firs emerging from under broadleaf litter allocated more dry mass to longer and thinner hypocotyls at the expense of cotyledon and root growth, albeit seeded on potting soil. This study identifies biomechanical constraints that severely reduce early seedling vigour suggesting that in situ survival under broadleaf litter is very low.

Well-documented shade adaptations include physiological and morphological traits of shoots and leaves. Belowground shade adaptations (roots or other buried structures) are rarely mentioned in the literature and have never been studied in tree seedlings. This study evaluates the functional role of adventitious roots developed by most balsam fir (Abies balsamea) seedlings under a closed canopy. Our goal was to describe the relationships between growth, biomass allocation, and adventitious root development in balsam fir seedlings (5–26 cm tall, 9 to 33 y old) excavated under a closed canopy (< 8% full sunlight). Seedling height, branch number and crown width increased linearly with stem diameter measured at ground level. The dry mass of stems and roots increased exponentially and tree vigour (photosynthetic/non-photosynthetic biomass ratio) decreased exponentially as stem diameter increased. Results indicate that shade tolerance is limited by size and concurrent radial increment at the stem base. Re...

This study examines the variability of the potential aging error for saplings (height ≤1.5 m) of black spruce (Picea mariana (Mill.) B.S.P.) in mature fire-dominated stands (n = 14 stands) of the northern boreal forest of northwestern Quebec. Age underestimation was determined by counting the number of underground bud scars of saplings. The magnitude and variability of age underestimation was compared within and among stands. The relationship between corrected ages (the sum of age underestimation and the number of growth rings at ground level) and ground-level ages was strongly linear and was therefore described with simple linear regression models. To evaluate landscape-level variability in this relationship, the regressions were compared among stands using mixed models. Despite high variability in age underestimation at the stand level, the relationship between corrected and ground-level age was highly significant (p

This study examines balsam fir (Abies balsamea (L.) Mill.) recruitment in old fir stands. Studying the regeneration of these stands is essential to understand the regeneration dynamic of the species in the absence of stand-destroying disturbances. The objectives were (1) to obtain substrate–seedling associations for different age-classes and according to the presence or absence of adventitious roots; (2) to evaluate the contribution of the seed rain to seedling recruitment; (3) to re-examine age structures using the most appropriate method that minimizes estimation errors due to the presence of adventitious roots. A total of 90 quadrats (1 m2) were established along transects. In each quadrat, subtrates were characterized (type and topography) and their area was estimated. All balsam fir seedlings (

The method of harvesting with protection of the advanced regeneration consists of a complete removal of the main canopy to release a seedling bank established under the overstory shade. After harvesting, seedlings acclimated to understory conditions could suffer from moisture stress, especially the small, juvenile seedlings (less than six years). The objective of the study is to determine the capacity of understory-acclimated balsam fir seedlings to respond positively and immediately to release. The response to release was studied in two seedling populations belonging to two distinct climatic regions of Quebec, the Western and the Eastern sections of the balsam fir-white birch ecological domain. Results show that the response patterns were similar in both populations. Response to release occurred in two steps. One year after harvesting, basal ring width was on the average five times larger than prior to harvesting (p > 0.001). Height growth only became significantly higher the second year after release (p < 0.001). On average, juveniles showed higher height growth rates (height growth/height) than older seedlings. This rate was negatively correlated to seedling height at harvesting (r = -0,68, p < 0.001). Our study clearly shows that balsam fir seedlings can respond immediately and positively to large openings. The strong response of juvenile seedlings to release indicates that these can contribute significantly to the future stand. The geographic and climatic differences between the two stands under study suggest that these observations apply to a wide range of balsam fir stands. Key words: advance growth, balsam fir, release

Numerous researchers have suggested a causal relationship between low leaf biomass in suppressed trees and the lack of radial growth at the base of the trunk. The objective of this study was to verify this relationship with suppressed balsam fir (Abies balsamea (L.) Mill.) saplings found growing in an old-growth fir stand. A total of 29 saplings varying in height from 67 to 183 cm were uprooted. All saplings had adventitious roots. All terminal bud scars (TBS) found between the apex of the terminal leader and the trunk base (first adventitious root) as well as those found below ground were localized, and rings were counted between TBS along the aboveground trunk. Various morphological traits and the ratio of photosynthetic tissue dry mass (P, needles) to non-photosynthetic tissue dry mass (nP, aboveground stem) were used as an indicator of tree vigour. Between 3 and 33 rings counted along the aboveground trunk were missing at the trunk base. The number of missing rings at the base of the trunk was correlated with total height (r = 0.41), height growth (r = –0.51), radial growth (r = –0.44), the P/nP ratio (r = –0.73), and the proportion of live crown (r = –0.62). Moreover, from 2 to 35 additional rings, missing at the trunk base, were found in the belowground section of trunk and these missing rings were associated with the adventitious roots phenomenon. In conclusion, suppressed firs had missing rings at the base of the trunk. When all of the missing rings were added to the number of rings counted at the base of the trunk, age estimates provided a different temporal pattern of recruitment compared with that obtained by solely counting rings at the base of the trunk. Stem analysis on the entire trunk is the best aging method for suppressed balsam fir saplings.

In many Canadian boreal forests, balsam fir (Abies balsamea (L.) Mill.) seedlings established under closed canopy generally develop adventitious roots. Adventitious roots induce the formation of a reverse taper, i.e., a reduction of the diameter and of the number of growth rings towards the true collar (hypocotyl region). Consequently, ring count at any level of the trunk underestimates the true age of firs, and we recommend a reassessment of balsam fir dynamics inferred from studies based on ages estimated by ring count. Recently, Kneeshaw and Claveau (D.D. Kneeshaw and Y. Claveau. 2001. Can. J. For. Res. 31: 1292-1295) presented data from a subsample of fir seedlings to demonstrate that ring count is an accurate aging technique for most fir regeneration. A careful examination of the methodology, data, and samples presented suggests that true collars were not precisely located. We also present data collected on seedlings sampled in the same study area as Kneeshaw and Claveau. Most of the seedlings (57 of 60 seedlings

The effects of recurrent spruce budworm (Choristoneura fumiferana(Clem.)) outbreaks on balsam fir (Abies balsamea (L.) Mill.) mortality have been extensively studied in Canada. Most studies report substantial seedling recruit - ment of balsam fir during outbreaks when reproductive trees are dying. According to previous research, this contradic - tion could be due to inaccuracies in the conventional aging method. Counting the maximum number of growth rings found at the tree base would significantly underestimate tree age. Counting terminal bud scars found on the entire trunk, including buried stem, would give a more accurate tree age. In this study, we compare recruitment dynamics ob- tained for aging seedlings in two balsam fir populations (about 500 km apart) using (i) the conventional method and (ii) bud scar counts. For both populations, the conventional method shows substantial recruitment during adult mortal- ity, while the second aging technique reveals reduced recruitment during the epidemic phase of the spruce budworm outbreak. Resume : Les effets des epidemies de la tordeuse des bourgeons de l'epinette (Choristoneura fumiferana(Clem.)) sur la mortalite des sapinieres boreales (Abies balsamea (L.) Mill.) ont ete largement documentes au Canada. La plupart des etudes rapportent un important recrutement de semis de sapin durant une epidemie alors que meurent les sapins matures. Selon la recherche auparavant, cette contradiction serait due a l'inexactitude de la methode conventionnelle- ment utilisee pour estimer l'âge des semis. Le decompte du nombre maximal de cernes de croissance a la base du tronc sous-estimerait de facon importante l'âge reel des semis. Le compte des cicatrices d'ecailles du bourgeon termi - nal sur tout le tronc, incluant la partie enfouie de la tige, serait une methode plus appropriee. La presente etude com - pare la dynamique du recrutement de deux populations de semis de sapin baumier lorsque l'âge est estime (i) par la methode conventionnelle et (ii) par le compte des cicatrices d'ecailles du bourgeon terminal sur tout le tronc. Environ 500 km separaient les deux populations. Dans les deux cas, la methode conventionnelle revele des structures d'âge dis- cordantes avec la mortalite des adultes. Par contre, les structures d'âge obtenues avec l'autre methode indiquent une re - duction du recrutement des semis durant la periode epidemique. Rapid communication / Communication rapide 376

The age structure of balsam fir (Abies balsamea (L.) Mill.) regeneration is frequently used to investigate boreal forest dynamics of North America. Tree ages are usually estimated by counting annual growth rings at the shoot-root interface located above or close to the root system. Inaccurately locating the shoot-root interface could lead to imprecise age determination. In this study, balsam fir seedlings (

The age structure of balsam fir (Abies balsamea (L.) Mill.) regeneration is frequently used to investigate boreal forest dynamics of North America. Tree ages are usually estimated by counting annual growth rings at the shoot-root interface located above or close to the root system. Inaccurately locating the shoot-root interface could lead to imprecise age determination. In this study, balsam fir seedlings (

Underplanting white pine (Pinus strobus L.) is a promising method to reduce competition and protect against white pine weevil (Pissodes strobi (Peck)) damage. However, shading caused by over-story trees can reduce growth, vigor and survival of white pine. The objective of this study was to determine the effects of a light gradient on the growth and overall crown morphology of white pine saplings planted in 3-meter strips within a hardwood forest some six years earlier. In 1994, we measured total height and diameter, leader length (in 1994) and numerous crown morphological variables. We then estimated the light environment above the crown of 63 young white pine saplings representing six families of close provenance. White pine grew well (i.e., > 20 cm in height/year) for the first six years when planted at light levels between 10 and 66% of full sunlight. Total height and diameter after six years tended to decline more sharply below 30% full sunlight, confirming earlier experiments made in controlled conditions. No significant changes in crown morphology were evident along the light gradient. This lack of crown morphological plasticity presumably contributes to limiting the ability of white pine to grow and compete in a very low light environment Various silvicultural options are discussed in light of the results obtained in this study. Key words: Understory growth, white pine, understory planting, crown morphology, silvicultural options, light gradient

The percentage of above-canopy Photosynthetic Photon Flux Density (%PPFD) was measured at 0, 50 and 100 cm above the forest floor and above the main understory vegetation in stands of (1) pure Betula papyrifera (White birch), (2) pure Populus tremuloides (Trembling aspen), (3) mixed broad-leaf-conifer, (4) shade-tolerant conifer and (5) pure Pinus banksiana (Jack pine) occurring on both clay and till soil types. %PPFD was measured instantaneously under overcast sky conditions (nine locations within each of 29 stands) and continuously for a full day under clear sky conditions (five locations within each of eight stands). The percentage cover of the understory layer was estimated at the same locations as light measurements. Mean %PPFD varied from 2% at the forest floor under Populus forests to 15% above the understory vegetation cover under Betula forests. Percent PPFD above the understory vegetation cover was significantly higher under shade intolerant tree species such as Populus, Betula and Pinus than under shade tolerant conifers. No significant differences were found in %PPFD above the understory vegetation cover under similar tree species between clay and till soil types. The coefficient of variation in %PPFD measured in the nine locations within each stand was significantly lower under deciduous dominated forests (mean of 19%) than under coniferous dominated forests (mean of 40%). %PPFD measured at the forest floor was positively correlated with %PPFD measured above the understory vegetation and negatively correlated with cumulative total percent cover of the understory vegetation (R2 = 0.852). The proportion of sunflecks above 250 and 500 I¼mol m-2 s-1 was much lower and %PPFD in shade much higher under Populus and Betula forests than under the other forests. Differences in the mean, variability and nature of the light environment found among forest and soil types are discussed in relation to their possible influences on tree succession.

This study presents a new, simple, and efficient method for estimating microsite light availability in the understory of a forest. The percentage of above-canopy photosynthetic photon flux density (%PPFD) transmitted above 16 microsites in the understory of a mixed conifer–broadleaf forest was measured every minute between 07:00 and 19:00 for both a completely overcast and a cloudless day. Instantaneous measures of %PPFD were also taken at different times on 3 overcast days. The instantaneous measures of %PPFD were strongly and directly related (P < 0.001) among themselves and with mean daily %PPFD values. These results demonstrate the usefulness of using an instantaneous measure of %PPFD taken under overcast sky conditions for estimating the mean daily %PPFD at any microsite under a forest canopy.

A l’exception de rares temoins encore bien conserves, comme la torre delle Milizie ou la torre dei Conti, aux abords des forums imperiaux, et de quelques eglises qui gardent dans leurs murs et leurs decorations le souvenir de cette periode, le Moyen Âge n’imprime que tres furtivement sa marque dans la trame urbaine contemporaine de Rome. La quasi-totalite des traces de cet urbanisme medieval a en effet ete emportee par l’« ouragan baroque » (J.-C. Maire Vigueur), qui a modifie en profondeur l...

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En 1335, l’inquisiteur de la Marche d’Ancone, le frere Lorenzo d’Ancona, decide d’annuler une sentence de condamnation pour heresie que l’un de ses predecesseurs, l’inquisiteur Lorenzo da Mondaino, avait prononcee contre les seigneurs de la petite ville d’Osimo au debut des annees 1320. Cette decision entraine l’ouverture d’une enquete par Benoit XII, qui convoque Lorenzo d’Ancona pour se justifier et produire sa defense. Jusqu’a present, seul un petit fragment de la defense produite par l’inquisiteur etait connu des historiens. La decouverte de vestiges inedits du proces en annulation conduit par Lorenzo, dont l’edition est proposee en annexe, nous incite a revenir sur une affaire qui souleve des questions juridiques de premier plan et temoigne des tensions qu’entraine l’exercice de la justice pontificale dans les premieres decennies du xive siecle.

International audience

International audience

The Impact of Papal Justice in the Diocese of Uzès under John XXII. In the 1320’s, Pope John XXII (1316-1334) carried out a series of trials for heresy against his own political enemies across the north and the centre of Italy. Among them were not only members of powerful noble families (the Viscontis, Estes, Montefeltros etc.), many minor lords as well as communities such as Recanati, Osimo or Spoleto, but also Emperor Ludwig IV from Bavaria. After their conviction as heretics, John XXII planned massive publications of the sentences in many dioceses across the west, in order to organize the crusade. The diocese of Uzès is particularly emblematic of the way theses publications were spread, from the bishopric to the most remote places of the diocese. It also shows the various actors of the preaching and the concrete organization of the publications., L’impact de la justice pontificale dans ie diocèse d’Uzès au temps de Jean XXII. Le pape Jean XXII (1316-1334) engagea dans les années 1320 une longue série de procès pour hérésie contre ses ennemis politiques dans toute l’Italie du Nord et du Centre. Parmi les accusés figuraient non seulement des membres des familles seigneuriales les plus puissantes (Les Visconti, les Este, les Montefeltro etc), de nombreux petits seigneurs locaux et des communautés comme Recanati, Osimo ou Spolète, mais aussi l’empereur Louis IV de Bavière. Après leur condamnation comme hérétiques, Jean XXII organisa une publication massive des sentences de condamnation dans de nombreux diocèses d’Occident, afin d’organiser la croisade. Le diocèse d’Uzès est particulièrement emblématique de la manière dont cette publication fut effectuée, depuis l’évêché jusque dans les endroits les plus reculés du diocèse. Il met aussi en lumière les différents acteurs qui ont contribué à ces prédications et le déroulement des publications., Parent Sylvain. L’impact de la justice pontificale dans le diocèse d’Uzès au temps de Jean XXII : la publication des procès contre les fils de Matteo Visconti et Louis de Bavière. In: Les Justices d'Église. Toulouse : Éditions Privat, 2007. pp. 287-316. (Cahiers de Fanjeaux, 42)

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