Population Dynamics of Rosebay Rhododendron Thickets in the Southern Appalachians

Plocher, Allen E.; Carvell, Kenneth L.

doi:10.2307/2996120

Cited by 25 publications

(24 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The light requirement for seed germination, except in R. simiarum, is consistent with field observations of an almost complete absence of seedlings in established populations, as has been reported in other rhododendron species (Plocher and Carvell 1987;Pornon and Doche 1995;Pornon and Escaravage 1999). Seedlings of R. farrerae, R. championii, and R. moulmainense were only found in small numbers in litter-free, open sites, while no seedlings at all were found for R. hongkongensis or R. simsii.…”

Section: Discussionsupporting

confidence: 85%

“…The production of numerous, tiny wind-dispersed seeds is also unusual for long-lived woody plant species, particularly in the tropics. This provides a great reproductive potential, but successful establishment from seed requires favourable microsites (Cross 1981;Plocher and Carvell 1987;Kohyama and Grubb 1994) and seedling recruitment is rare in some Rhododendron species (Pornon and Doche 1995).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Comparative reproductive biology of the six species of Rhododendron (Ericaceae) in Hong Kong, South China

Ng¹,

Corlett²

2000

Can. J. Bot.

View full text Add to dashboard Cite

Six rhododendron species grow wild in Hong Kong: Rhododendron farrerae Tate and Rhododendron simsii Planch. are common and widespread, Rhododendron moulmainense Hook. f. is restricted, and Rhododendron championiae Hook. f., Rhododendron hongkongense Hutch., and Rhododendron simiarum Hance are rare. The length and timing of the flowering period varied between species, but peak flowering for all was between late February and early May, when weather is variable and unpredictable. All species were more or less self-sterile, had sucrosedominated nectar, and were visited by diverse insects, of which Apis cerana, Bombus eximius, and Xylocopa spp. are the major pollinators. Seeds of all species, except R. simiarum, had a light requirement for germination. There were large differences between species in the pollen/ovule ratio (176-1343), daily nectar production (0.9-38.7 µL per flower), large bee visits (0.35-4.28 per flower per 100 h) and total visits (0.92-14.53), mean seed production per flower (2-135) and per plant (100 -14 800), and mean seed weight (0.11-0.45 mg). The large-bee visitation rate was significantly correlated across species with mean daily nectar production and mean seed set. The two common species had the smallest flowers, lowest nectar production, lowest pollen/ovule ratios, fewest large bee visitors, and produced fewest seeds. Résumé: Il y a six espèces de rhodendron qui pousse à l'état sauvage à Hong-Kong: le Rhododendron farrerae Tate et le Rhododendron simsii Planch. sont communs et répandus, le Rhododendron moulmainense Hook. f. est restreint, et les Rhododendron championiae Hook. f., Rhododendron hongkongense Hutch. et Rhododendron simiarum Hance sont rares. La longeur et le moment de la période de floraison varient selon les espèces mais atteignent un sommet, chez toutes les espèces, entre la fin de février et le début de mai, période où la température est variable et imprévisible. Toutes les espèces sont plus ou moins auto-stériles, produisent un nectar dominé par le sucrose et sont visitées par divers insectes parmi lesquelles les Apis cerana, Bombus eximius et Xylocopa spp. sont les pollinisateurs principaux.Les graines de toutes les espèces, sauf celles du R. simiarum, ont besoin de lumière pour germer. Il y a de grandes diffé-rences entre les espèces dans le rapport pollen/ovule (176-1343), dans la production quotidienne de nectar (0,9-38,7 µL par fleur), dans le nombre de visites par de grosses abeilles (0,35-4,28 par fleur par 100 h) et le nombre total de visites (0,92-14,53), dans le nombre moyen de graines produites par fleur (2-135) et par plante (100 -14 800), et dans le poids moyen des graines (0,11-0,45 mg). Le taux de visite par les grosses abeilles montre une corrélation significative parmi les espèces avec la production quotidienne moyenne de nectar et le nombre moyen de graines formées. Les deux espèces les plus communes ont les fleurs les plus petites, la production de nectar la plus faible, les plus faibles rapports pollen/ovule, le plus petit nombre de visites par les grosse...

show abstract

Section: Discussionsupporting

confidence: 85%

Section: Introductionmentioning

confidence: 99%

Comparative reproductive biology of the six species of Rhododendron (Ericaceae) in Hong Kong, South China

Ng¹,

Corlett²

2000

Can. J. Bot.

View full text Add to dashboard Cite

show abstract

“…Indeed, the results of this research in conjunction with others (Rooney et al 2000;Kincaid 2008, submitted) have elucidated a link between canopy openness or disturbance and Tsuga canadensis regeneration. Because Rhododendron maximum has been shown to invade canopy gaps easily (Ploucher and Carvell 1987;Dobbs and Parker 2004), and it is well known that this species often precludes the regeneration of Tsuga canadensis, as well as other tree species (Monk et al 1985;Hedman and Van Lear 1995;Van Lear et al 2002), any silvicultural treatment resulting in canopy gap creation may also have to include Rhododendron maximum removal to further promote tree regeneration. The baseline information provided by this research and future studies can aid land managers in the promotion of Tsuga canadensis regeneration in areas where treatment against hemlock woolly adelgid infestation is successful.…”

Section: Disturbance Regimesmentioning

confidence: 98%

“…Rhododendron maximum L. has been reported to be expanding along streamsides and in cooler, more mesic areas in the southern Appalachian Mountains (Dobbs and Parker 2004). This species easily expands in response to disturbance, including individual tree-fall gaps (Ploucher and Carvell 1987;Dobbs and Parker 2004); therefore, canopy gap formation that could facilitate Tsuga canadensis regeneration may lead to understory Rhododendron maximum expansion instead. While this may be the case at BFR-I with a Rhododendron maximum understory cover of 66.7%, it is not the case at BGM.…”

Section: Forest-environmental Characteristicsmentioning

confidence: 99%

Structural characteristics and canopy dynamics of Tsuga canadensis in forests of the southern Appalachian Mountains, USA

Kincaid

Parker

2008

Plant Ecol

View full text Add to dashboard Cite

show abstract

“…L. Dobbs and Parker 2004). Members of this genus, especially Rhododendron maximum L. (rosebay rhododendron), thrive in acidic soils and have been shown to reduce the recruitment of other woody species and decrease the cover and diversity of the herbaceous layer as a result of direct competition, modification of understory microclimate, and changes to upper soil horizons resulting from heavy accumulation of slow decaying acidic litter (Monk et al 1985;Phillips and Murdy 1985;Plocher and Carvell 1987;Clinton et al 1994;Nowacki and Abrams 1994;Clinton 2003;Brantley and Young 2010). Rhododendron thickets have also been shown to alter N cycling and soil extracellular enzyme activity (Wurzburger and Hendrick 2007).…”

Section: Introductionmentioning

confidence: 99%

High‐elevation ground‐layer plant community composition across environmental gradients in spruce‐fir forests

Stehn

Webster

Jenkins

et al. 2011

Ecological Research

View full text Add to dashboard Cite

We examined the influence of vegetation structure and soil chemistry on post-adelgid, ground-layer plant communities in high-elevation forests of the southern Appalachian Mountains. Specifically, we hypothesized that post-disturbance community composition and diversity would vary along a gradient of soil acidity and other soil characteristics influenced by acid deposition. Ground-layer vegetation and soils were sampled on 60 randomly located nested vegetation plots in the spruce-fir (Picea abies) zone of Great Smoky Mountains National Park, TN and NC, USA. To capture a range of deposition levels, plot placement was stratified based on modeled acid deposition classes. Ordination and multiple regression results showed that ground-layer composition and diversity were negatively associated with acidity of the A horizon and the presence of ericaceous shrubs (i.e., Rhododendron spp.). A strong correspondence between soil acidity and ericaceous shrub cover was also observed, suggesting that soil acidity may be, in conjunction with overstory disturbance resulting from chronic acid deposition and adelgid induced mortality, an important driver of ericaceous shrub thicket expansion. Slow-decaying, acidic ericaceous litter may also induce a positive feedback resulting in enhanced acidification.

show abstract

Population Dynamics of Rosebay Rhododendron Thickets in the Southern Appalachians

Cited by 25 publications

References 4 publications

Comparative reproductive biology of the six species of Rhododendron (Ericaceae) in Hong Kong, South China

Comparative reproductive biology of the six species of Rhododendron (Ericaceae) in Hong Kong, South China

Structural characteristics and canopy dynamics of Tsuga canadensis in forests of the southern Appalachian Mountains, USA

High‐elevation ground‐layer plant community composition across environmental gradients in spruce‐fir forests

Contact Info

Product

Resources

About