@article {KNZ001700, title = {Breeding system and sex ratio variation in mulberries}, journal = {Journal of the Botanical Research Institute of Texas}, volume = {9}, year = {2015}, pages = {383-395}, abstract = {Flowering plants exhibit a diverse array of sex expression patterns that become of particular interest when considered in the context of coexisting native-invasive congeners. This study presents findings on sex expression and sex ratio variation in two congeneric tree species, the native Morus rubra and the exotic M. alba, in the Flint Hills region of the Great Plains in the United States. Both species exhibited a subdioecious breeding system (with male, female and hermaphrodite individuals co-occurring within populations), and significantly male-biased sex ratios (i.e., males are more numerous than females). Cumulative sex ratio deviation was higher in the native M. rubra populations than in the exotic M. alba. Within-species sex ratio did not vary significantly among populations. In one focus study area surveyed over three years, most individuals were consistent in sex expression, but approximately 10\% switched their sex at least once; the vast majority of these changes were between unisexual and hermaphrodite morphs. There was no size dependence of sex expression based on current sampling. Our results document subdioecy as the breeding system in these Morus species, and advance the group as an interesting study system for its reproductive biology. }, keywords = {LTER-KNZ, Breeding system, Moraceae, Morus, sex ratio, sex switch, subdioecy}, issn = {1934-5259}, author = {Nepal, M.P. and Ferguson, C.J. and Mayfield, M.H.} } @article {KNZ001666, title = {Timing is everything: temporal variation in floral scent, and its connections to pollinator behavior and female reproductive success in Phlox divaricata}, journal = {American Midland Naturalist}, volume = {173}, year = {2015}, pages = {191 -207}, abstract = {

The study of floral traits and pollination for the plant genus Phlox has historically been focused on either surveys of general pollinator affinities across the genus or detailed research on pollinator-mediated evolution of floral color in a single species (Phlox drummondii). The purpose of this study was to explore a different kind of trait \– floral scent \– in Phlox divaricata, a species noted for its strong scent. Specifically, we predicted the diel emission patterns of floral scent might covary with the daily abundance of diurnal moths, identified in a previous study as the most important pollinators in a Konza Prairie population of P. divaricata. Consistent with this prediction, we documented peaks in median floral scent emissions at 1000\–1200 and 1930\–2130, coinciding with peaks in moth visitation and resulting seed production. Two groups of scent compounds contributed to this pattern; linalool and its associated lilac aldehyde/alcohol compounds (especially lilac aldehyde B) contributed a greater proportion to scent at 1000\–1200, while aromatic compounds (including benzaldehyde and benzyl acetate) contributed a greater proportion to scent at 1930\–2130 and other afternoon time periods. These volatiles are known floral attractants for several lepidopteran pollinators, including noctuid moths. However, there is an additional peak in pollinator abundance (Hemaris diurnal hawkmoths) and seed set at a time when scent production is relatively low (1400\–1600) suggesting additional factors mediate both pollinator behavior and floral volatile emissions. Future studies of P. divaricata should test for the presence of destructive floral enemies that might be attracted by floral volatiles during mid-afternoon periods, as well as the importance of visual floral traits (color, shape) in attracting diurnal moths, an important functional group of pollinators that has received minimal attention in North America.

}, keywords = {LTER-KNZ}, doi = {10.1674/amid-173-02-191-207.1}, url = {https://doi.org/10.1674/amid-173-02-191-207.1}, author = {Majetic, C.J. and Wiggam, S.D. and Ferguson, C.J. and Raguso, R.A.} } @article {KNZ001458, title = {The invasive Lespedeza cuneata attracts more insect pollinators than native congeners in tallgrass prairie with variable impacts}, journal = {Biological Invasions}, volume = {14}, year = {2012}, pages = {1045 -1059}, abstract = {

Invasive plant species can potentially exert competitive or facilitative effects on insect pollination services of native species. Factors that influence these effects include the degree of shared pollinator species, synchronous flowering phenology, similar flower morphology and color, relatedness of invasive and natives, and showiness and densities of flowers. We investigated such plant-pollinator dynamics by comparing the invasive Lespedeza cuneata and three native congeners, all sympatric with synchronous flowering, using in situ populations over 2 years during peak floral displays. Insect visitation rates of the invasive were significantly higher per plant in both years than on the native species. The invasive exerted a competitive effect on visitation of the two native species with fewer shared pollinators, and a facilitative effect on visitation of the native species with the highest degree of shared insect visitors. Positive correlations were found between floral density and visitation rate per plant in all the native species. Although no such correlation was found for the invasive, floral density in L. cuneata was at least twenty times higher than in the native species and likely saturated the response of the pollinator community. Analyses of insect visitor taxonomic data indicated the insect communities visiting each of the Lespedeza species were generally similar though with species-specific differences. The main exception was that the common honeybee, Apis mellifera, was a primary visitor to the invasive plant species, yet was never observed on the native Lespedeza species.

}, keywords = {LTER-KNZ, Apis mellifera, Competition, Facilitation, Invasive, Lespedeza, Pollination}, doi = {10.1007/s10530-011-0138-0}, url = {https://link.springer.com/article/10.1007\%2Fs10530-011-0138-0}, author = {Woods, T.M. and Jonas, J.L. and Ferguson, C.J.} } @article {KNZ001457, title = {Phylogenetics of Morus (Moraceae) inferred from ITS and trnL-trnF sequence data}, journal = {Systematic Botany}, volume = {37}, year = {2012}, pages = {442 -450}, abstract = {

Morus (Tribe Moreae, Moraceae) consists of ca. 13 species of trees distributed in Asia, Africa, Europe, and North, Central, and South America. The broad geographical distribution of the genus, overlapping ranges of many taxa, and documented hybridization between some species present interesting questions of taxonomy, phylogeny, and biogeography. Phylogenetic data for Morus also contribute to higher level taxonomic work in the family. We used sequence data from ITS of the nrDNA and the chloroplast trnL-trnF intergenic spacer to study phylogenetic relationships of Morus. Phylogenies based on separate data sets were not statistically incongruent, and the combined tree reveals that Morus, as currently circumscribed, is non-monophyletic. Subgenus Morus (sensu Leroy) is resolved as a clade and consists of two well-supported clades: one of Asian taxa and one of North American taxa. Sampled members of the genus Trophis (two, including the type) form a clade sister to subgenus Morus. Morus mesozygia (Africa; subgenus Afromorus) and M. insignis (Neotropics; subgenus Gomphomorus), which have not been included to date in other phylogenetic studies of the family, are placed outside the subgenus Morus-Trophis clade. This work is an important step in elucidating relationships of Morus and along with other recent phylogenetic studies in Moraceae, underscores the need for further work within Tribe Moreae to clarify natural generic relationships.

}, keywords = {LTER-KNZ, ITS, Moraceae, Moreae, Morus, phylogeny, trnL-trnF}, doi = {https://doi.org/10.1600/036364412X635485}, url = {https://bioone.org/journals/Systematic-Botany/volume-37/issue-2/036364412X635485/Phylogenetics-of-iMorus-i-Moraceae-Inferred-from-ITS-and-itrnL/10.1600/036364412X635485.full}, author = {Nepal, M.P. and Ferguson, C.J.} } @article {KNZ001304, title = {Thirteen decades of foliar isotopes indicate declining nitrogen availability in central North American grasslands}, journal = {New Phytologist}, volume = {187}, year = {2010}, pages = {1135 -1145}, abstract = {

\•Humans are increasing both the deposition of reactive nitrogen (N) and concentrations of atmospheric CO2 on Earth, but the combined effects on terrestrial ecosystems are not clear. In the absence of historical records, it is difficult to know if N availability is currently increasing or decreasing on regional scales. \•To determine the nature and timing of past changes in grassland ecosystem dynamics, we measured the composition of stable carbon (C) and N isotopes in leaf tissue from 545 herbarium specimens of 24 vascular plant species collected in Kansas, USA from 1876 to 2008. We also parameterized a simple model of the terrestrial N cycle coupled with a stable isotope simulator to constrain processes consistent with observed patterns. \•A prolonged decline in foliar N concentrations began in 1926, while a prolonged decline in foliar δ15N values began in 1940. Changes in the difference between foliar and atmospheric C isotopes reveal slightly increased photosynthetic water use efficiency since 1876. \•The declines in foliar N concentrations and foliar δ15N suggest declining N availability in these grasslands during the 20th century despite decades of anthropogenic N deposition. Our results are consistent with progressive-nitrogen-limitation-type hypotheses where declines in N availability are driven by increased ecosystem N storage as a result of increased atmospheric CO2.

}, keywords = {LTER-KNZ}, doi = {10.1111/j.1469-8137.2010.03322.x}, url = {https://nph.onlinelibrary.wiley.com/doi/full/10.1111/j.1469-8137.2010.03322.x}, author = {McLauchlan, K.K. and Ferguson, C.J. and Wilson, I.E. and Ocheltree, T.W. and Craine, J.M.} } @article {KNZ001286, title = {High propagule production and reproductive fitness homeostasis contribute to the invasiveness of Lespedeza cuneata (Fabaceae)}, journal = {Biological Invasions}, volume = {11}, year = {2009}, pages = {1913 -1927}, abstract = {

Comparative studies of congeneric native and exotic species have proved fruitful in understanding plant traits that foster invasion. Using this approach, we investigate the complex reproductive system of the invasive Lespedeza cuneata (Dum.-Cours.) G. Don in relation to three native congeners in the variable environment of the North American tallgrass prairie. Lespedeza species produce both chasmogamous (CH) and cleistogamous (CL) flowers, and propagate clonally via vegetative buds. Utilizing multiple natural populations over 2 years, we investigated reproductive modes of individuals from bagged and unbagged treatments of each species. We found that L. cuneata produced a mean of five times as many seeds and a significantly greater number of vegetative buds than any native studied, and over twenty times as many CH flowers. Insect visitation significantly affected seed set in CH flowers, though some autonomous CH selfing occurred in all species. The invasive relied relatively less on selfing than the natives and exhibited less variation in reproductive output from both modes of reproduction. We conclude that the diverse reproductive biology and wide regeneration niche of L. cuneata in relation to its native congeners confer a fitness homeostasis that facilitates the successful spread of this invasive under a wide range of conditions.

}, keywords = {LTER-KNZ, Cleistogamy, Fitness homeostasis, Invasive, Lespedeza, Pollination, Propagule production, Regeneration niche, tallgrass prairie}, doi = {10.1007/s10530-008-9369-0}, url = {https://link.springer.com/article/10.1007\%2Fs10530-008-9369-0}, author = {Woods, T.M. and D.C. Hartnett and Ferguson, C.J.} } @article {KNZ001062, title = {Introduced species in Kansas: floristic changes and patterns of collection based onan historical herbarium}, journal = {Sida}, volume = {21}, year = {2005}, pages = {1695 -1725}, keywords = {LTER-KNZ}, author = {Woods, T.M. and Strakosh, S.C. and Nepal, M.P. and Chakrabarti, S. and Simpson, N.B. and Mayfield, M.H. and Ferguson, C.J.} } @article {KNZ00959, title = {Pollinator importance andtemporal variation in a population of Phlox divaricata L. (Polemoniaceae)}, journal = {American Midland Naturalist}, volume = {154}, year = {2005}, pages = {42 -54}, abstract = {Temporal variation in climatic conditions is a regular occurrence for most early spring flowering plants in temperate regions, often producing variation in available pollinators. Evaluating the effectiveness and importance of pollinators to a plant population provides an indication of the relative influence of each visitor on a population{\textquoteright}s reproductive success and selection on floral traits. This study examined pollinator activity and its effect on seed set in a population of Phlox divaricata L. (Polemoniaceae), investigating variation over the 24-h day and the flowering season for two consecutive years. Eleven species, representing three orders of insects, were documented visiting the study population, although lepidopterans (four species, particularly Hemaris diffinis and Megalographa biloba) accounted for 90\% of all visitation. The highest visitation rates (and resulting seed set) occurred during the morning and afternoon diurnal time periods and the evening crepuscular time period. The relative frequencies of the different visitors varied over the 24-h day and between flowering seasons. Most visitors that could be evaluated were found to be effective pollinators. Thus, a pollinator{\textquoteright}s importance to reproductive success was generally dictated by its visitation frequency, H. diffinis being the most important pollinator. This study highlights the importance of considering temporal variation in effective pollinators in species experiencing variable environmental conditions.}, keywords = {LTER-KNZ}, doi = {10.1674/0003-0031(2005)154[0042:PIATVI]2.0.CO;2}, author = {Wiggam, S. and Ferguson, C.J.} }