scholarly journals Helenium amarum (bitterweed).

2020 ◽  
Author(s):  
Shruti Dube
Keyword(s):  
North America ◽  
Herbaceous Plant ◽  
Substantial Portion ◽  
Native Range ◽  
Invasive Weed ◽  
Grazing Land ◽  
The Usa ◽  
Environmental Weed ◽  
Open Fields

Abstract Helenium amarum is an annual herbaceous plant native to North America. It is native to some states in America, but introduced in California, Connecticut, Maryland and Massachusetts. It has also been introduced in Queensland, Australia. H. amarum is potentially weedy in many of the areas in which it grows. It is an opportunistic colonizer that will quickly spread into areas when taller vegetation is removed, and has the potential to become abundant in open fields, roadsides and wastelands. It is poisonous to most mammals, and if eaten by cows will cause their milk to become bitter and unusable. Helenium amarum is classed as an invasive weed in the USA, where it has spread widely in its native range and now covers a substantial portion of the grazing land in Texas. In Queensland, Australia is is considered an environmental weed and subject to control efforts. It was reported as eradicated in 2002 but has since been identified as present in low numbers.

Chrysomyxa abietis (needle rust of fir).

2021 ◽  
Author(s):  
Keyword(s):  
Life Cycle ◽  
New Zealand ◽  
North America ◽  
Rust Fungus ◽  
Significant Problem ◽  
Northern Europe ◽  
Native Range ◽  
Obligate Parasite ◽  
The Usa ◽  
Accidental Introduction

Abstract C. abietis is a microcyclic rust fungus; an obligate parasite completing its life cycle on species of Picea (spruce). Only the current year's needles of Picea are infected and those needles are shed early. Reported from northern Europe and Asia, the fungus is a Regulated Pest for the USA. It is absent from North America, where susceptible species are native, and Australia and New Zealand, where they are introduced. Although usually not a significant problem in its native range, because conditions are not favourable for heavy infections every year (Smith et al., 1988; Hansen, 1997), this rust could be more damaging as an invasive in other temperate areas. Due to the fact that small amounts of infection may be overlooked, accidental introduction could occur through importation of infected seedlings or young trees.

scholarly journals Foeniculum vulgare (fennel).

2020 ◽  
Author(s):  
Marianne Jennifer Datiles ◽  
Ian Popay
Keyword(s):  
New Zealand ◽  
Agricultural Land ◽  
Fire Regimes ◽  
Foeniculum Vulgare ◽  
Natural Habitats ◽  
Invasive Weed ◽  
Editorial Committee ◽  
Native Flora ◽  
The Usa ◽  
Environmental Weed

Abstract Foeniculum vulgare, also known as sweet fennel, is a common kitchen herb used around the world - but it is also a highly invasive weed that can severely damage ecosystems. A risk assessment prepared for Hawaii gave the species a high risk score of 19 (PIER, 2015). F. vulgare is known to alter fire regimes and create dense stands, outcompeting native flora for nutrients and space (DiTomaso et al., 2013; Cal-IPC, 2015). It was listed in the Global Compendium of Weeds as an "agricultural weed, casual alien, cultivation escape, environmental weed, garden thug, naturalised, noxious weed, weed" (Randall, 2012), and is known to be invasive (mostly in natural habitats rather than agricultural land) in California, New Zealand, significant parts of Australia and a number of locations in the Pacific. (PIER, 2015). The species is a principal weed in Mexico and New Zealand, a common weed in Argentina, Australia, Hawaii, and Spain, weedy in Chile, Morocco, Uruguay, the USA, and Venezuela, and it is known to be adventive in China, Colombia (Holm et al., 1979; Flora of China Editorial Committee, 2015; PIER, 2015; Vascular Plants of Antioquia, 2015). It is also reported as invasive in Ethiopia and Kenya. It can regenerate by both seeds and roots, which often makes physical control methods ineffective and chemical control necessary once a population is established.

Thekopsora areolata (cherry spruce rust).

2021 ◽  
Author(s):  
Keyword(s):  
Life Cycle ◽  
New Zealand ◽  
North America ◽  
Rust Fungus ◽  
Native Range ◽  
Obligate Parasite ◽  
The Usa ◽  
The One ◽  
Accidental Introduction

Abstract T. areolata is a heteroecious rust fungus; an obligate parasite with stages of its life cycle on cones of Picea species and leaves of Prunus spp. Reported from Europe and Asia, the fungus is a Regulated Pest for the USA. It is absent from North America, where susceptible species are native or introduced, and Australia and New Zealand, where such species are introduced. Although usually not a major problem in its native range, this rust could be more damaging as an invasive in other temperate areas. Due to the fact that small amounts of infection may be overlooked, accidental introduction could occur through importation of infected cones carrying aeciospores. The one known introduction to North America involved a tree of Prunus sp. in a garden, from which there was no documented spread.

Pilosella aurantiaca (orange hawkweed).

2021 ◽  
Author(s):  
Ghislaine Cortat ◽  
Gitta Grosskopf
Keyword(s):  
New Zealand ◽  
North America ◽  
Seed Production ◽  
Vegetative Growth ◽  
Perennial Herb ◽  
Native Range ◽  
Hieracium Pilosella ◽  
The Usa ◽  
Noxious Weed ◽  
Vegetation Loss

Abstract P. aurantiaca is a perennial herb which has spread rapidly in North America after its introduction as an ornamental and/or the contamination of pasture seeds from its native range in Europe. Although it is known to be a noxious weed elsewhere, it continues to be available as a garden ornamental and is therefore likely to spread further. It is an undesirable invader on account of its competitiveness, prolific seed production and vigorous vegetative growth leading to a drastic change in vegetation, loss in forage for stock, and loss of biodiversity. All Hieracium/Pilosella species are prohibited entry to Australia and New Zealand, and in the USA, P. aurantiaca is a declared weed in Colorado, Idaho, Minnesota and Washington.

scholarly journals Myriophyllum pinnatum (cutleaf watermilfoil).

2020 ◽  
Author(s):  
Jeanine Vélez-Gavilán
Keyword(s):  
New York ◽  
Invasive Species ◽  
North America ◽  
Habitat Fragmentation ◽  
Rhode Island ◽  
Biosphere Reserve ◽  
Management Plan ◽  
Native Range ◽  
The Usa ◽  
Wetland System

Abstract Myriophyllum pinnatum is a perennial aquatic herb only reported as invasive in Cuba, where it is included in the management plan of the Ciénaga de Zapata Biosphere Reserve as a species that needs to be managed to prevent invasion of that wetland system. In some areas of its native range in North America, it is considered rare, endangered or extirpated due to habitat fragmentation and loss. In the USA, the species is considered endangered in Connecticut, Massachusetts, Indiana, New Jersey, New York, Rhode Island and Tennessee. M. pinnatum belongs to a genus recognized for the invasive species M. spicatum, M. aquaticum and M. heterophyllum.

scholarly journals Herbaceous plant species diversity in communal agro-pastoral and conservation areas in western Serengeti, Tanzania

2019 ◽  
Vol 7 (5) ◽  
pp. 502-518
Author(s):  
Pius Yoram Kavana ◽  
Anthony Z. Sangeda ◽  
Ephraim J. Mtengeti ◽  
Christopher Mahonge ◽  
John Bukombe ◽  
...  
Keyword(s):  
Species Diversity ◽  
Protected Areas ◽  
Plant Species ◽  
Rural Areas ◽  
Plant Species Diversity ◽  
Livestock Grazing ◽  
Herbaceous Plant ◽  
Herbaceous Species ◽  
Grazing Land ◽  
Grazing Lands

Agro-pastoralism involves the growing of crops and keeping of livestock as a livelihood strategy practiced by communities in rural areas in Africa and is highly dependent on environmental factors including rainfall, soil and vegetation. Agro-pastoral activities, e.g. livestock grazing and land clearing for crop cultivation, impact on environmental condition. This study evaluated the impacts of agro-pastoral activities on herbaceous plant species diversity and abundance in western Serengeti relative to conservation (protected) areas. A vegetation survey was conducted along the grazing gradients of ten 4 km transects from within village lands to protected areas. A total of 123 herbaceous species belonging to 20 families were identified. Higher herbaceous species diversity and richness were found in protected areas than in communal grazing lands. Similarly, the number of perennial herbaceous species was higher in the former than the latter, while occurrence of annuals was higher in the village areas. This observation indicates poor rangeland condition in village communal grazing lands as compared with protected areas. It is obvious that current agro-pastoral activities have contributed to a reduction in herbaceous species diversity in village lands in western Serengeti. However, the array of pasture species, especially desirable perennial species, still present in communal grazing areas, suggests that rejuvenation of these areas is possible. Resting of grazing land is recommended to reverse the trend towards diversity reduction and ensure future availability of feed resources for grazing animals in village lands.

scholarly journals Big and beautiful: the Megaxyela species (Hymenoptera, Xyelidae) of East Asia and North America

2017 ◽  
Author(s):  
Stephan M. Blank ◽  
Katja Kramp ◽  
David R. Smith ◽  
Yuri N. Sundikov ◽  
Meicai Wei ◽  
...  
Keyword(s):  
North America ◽  
West Virginia ◽  
South Korea ◽  
East Asia ◽  
Morphological Characters ◽  
Old World ◽  
Eastern Usa ◽  
The Usa ◽  
Coi Sequences ◽  
First Time

Megaxyela Ashmead, 1898 comprises 13 species, four of which are described as new and one is removed from synonymy: Megaxyela euchroma Blank, Shinohara & Wei sp. nov. from China (Zheijang), M. fulvago Blank, Shinohara & Wei sp. nov. from China (Hunan, Jiangsu, Zhejiang), M. inversa Blank & D.R. Smith sp. nov. from the USA (West Virginia), M. langstoni Ross, 1936 sp. rev. from the eastern USA, and M. pulchra Blank, Shinohara & Sundukov sp. nov. from China (Hubei, Jilin, Liaoning, Shaanxi, Tibet), South Korea (Kangwon-do) and Russia (Primorskiy Kray). The male of M. parki Shinohara, 1992 is described for the first time. A lectotype is designated for M. gigantea Mocsáry, 1909. A cladogram, based on COI sequences of seven species, is presented and interpreted in view of selected morphological characters. Records of M. fulvago sp. nov. from Hunan and of M. pulchra sp. nov. from Tibet extend the known distribution of Megaxyela in the Old World 600 kilometers farther south and 2500 kilometers farther west than previous records.

scholarly journals Variability of nitrogen content in the needles of Douglas-fir (Pseudotsuga menziesii Mir/Franco) provenances

Genetika ◽  
2011 ◽  
Vol 43 (2) ◽  
pp. 407-417 ◽  
Author(s):  
Vera Lavadinovic ◽  
Vasilije Isajev ◽  
Zoran Miletic ◽  
Milun Krstic
Keyword(s):  
Nitrogen Content ◽  
Mineral Nutrition ◽  
Douglas Fir ◽  
Native Range ◽  
Adaptive Potential ◽  
Small Areas ◽  
Physiological Processes ◽  
Provenance Test ◽  
The Usa ◽  
Geographical Characteristics

Nitrogen content in the needles of twenty Douglas-fir provenances, originating from different sites within the native range of the species in the USA, was studied in a Douglas-fir provenance test established at the montane beech site on acid brown soil. Based on the variability of nitrogen content in the needles, the intensity and dynamics of the physiological processes of Douglas-fir mineral nutrition were analyzed as the indicators of Douglas-fir adaptive potential to the sites in Serbia. All the trees of the study provenances were of the same age and grown under the same site and population conditions. The quantities of nitrogen absorbed in Douglas-fir needles were correlated with the geographical characteristics of the native sites of the observed provenances. The differences in nitrogen content in Douglas-fir needles point out the variability in the intensity of the physiological processes in the genotypes of the different provenances. Since the study Douglas-fir trees are cultivated on relatively small areas, in more or less equal general conditions, it can be concluded that the parameters of mineral nutrition depend on the genotypes constituting the gene pool of the study Douglas-fir provenances.

Puccinia buxi.

2021 ◽  
Author(s):  
Keyword(s):  
Life Cycle ◽  
North America ◽  
Southern Hemisphere ◽  
Latent Infections ◽  
Growth And Survival ◽  
The Usa

Abstract P. buxi is an autoecious microcyclic rust, completing its life cycle with two spore forms on one host. It is native to parts of Europe and Asia. An introduction to the USA, is evidence that it can be invasive with respect to other temperate countries, particularly because its hosts in the genus Buxus are often propagated vegetatively and may carry latent infections. Boxwoods have long been popular as ornamentals, therefore the rust's current absence from North America and temperate regions of the southern hemisphere is puzzling; in the earliest introductions of the host, the pathogen would probably have been ignored or overlooked. Conditions of boxwood cultivation may discourage the rust's growth and survival.

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