Bionomic notes on the solitary Evylaeus oenotherae (Stevens) (Hymenoptera: Halictinae), a matinal summer bee visiting cultivated Onagraceae

1969 ◽  
Vol 47 (3) ◽  
pp. 289-294 ◽  
Author(s):  
Gerd Knerer ◽  
Patricia MacKay
Keyword(s):  
Food Source ◽  
Active Phase ◽  
Breeding Population ◽  
Early Summer ◽  
Flowering Period ◽  
Nest Competition

Overwintered females of Evylaeus oenotherae establish haplometrotic nests in aggregations and rear a single annual generation in from 12 to 20 cells per nest. Competition for suitable nests in early summer appears to keep the breeding population at a certain level and prevents the overexploitation of its exclusive food source, Oenothera pollen. The bee's late active phase is synchronized with the flowering period of the host in June and July. Initially, females are active in the morning and evening, but are quickly trained to a matinal rhythm only, when excursions in the evening fail to yield suitable food.

Variation in seasonal stocking rate and the dynamics of Lotononis bainesii in Digitaria decumbens pastures

1992 ◽  
Vol 118 (1) ◽  
pp. 47-53
Author(s):  
H. Fujita ◽  
L. R. Humphreys
Keyword(s):  
Ecological Niche ◽  
Large Scale ◽  
Late Summer ◽  
Early Summer ◽  
Flowering Period ◽  
Stocking Rate ◽  
Seedling Density ◽  
Digitaria Decumbens ◽  
Cotton South ◽  
Seed Reserves

SUMMARYPastures of Digitaria decumbens (pangola grass) previously oversown with Lotononis bainesii at Mount Cotton, south-east Queensland, Australia, were grazed by sheep for 3 years (1985–87), using a factorial combination of seasonal variations in stocking rate.Lotononis behaved as a short-lived plant with a mean half-life of 4·2 months (range 1·6–10·3); rate of mortality was positively related to initial seedling density. The proportion of lotononis remained very low for the first 2 years of the experiment, when conditions were unsuitable for large-scale seedling regeneration, which was also limited by the hardness of the seed reserves. Subsequently, lotononis regenerated well in treatments which combined the following features: (i) light grazing (5 sheep/ha) during the main flowering period of spring-early summer, (ii) heavy short-duration grazing in mid-summer to create a ‘gap’ and (iii) medium or heavy (18 or 27 sheep/ha) grazing during late summer-autumn to reduce competition from pangola grass.The ecological niche of lotononis and the possible use of complementary pastures are discussed.

scholarly journals Colecția genului Spiraea L., în Grădina Botanică Națională (Institut) “Alexandru Ciubotaru”

2021 ◽  
Author(s):  
Tatiana Tanachi ◽  
◽  
Ion Rosca ◽  
Elisaveta Onica ◽  
Alina Cutcovschii-Mustuc ◽  
...  
Keyword(s):  
New Taxa ◽  
Small Groups ◽  
Growing Season ◽  
Early Spring ◽  
Early Summer ◽  
Special Care ◽  
Appropriate Technology ◽  
Flowering Period ◽  
Shape And Size

Fourteen new taxa have been added to the collection of the genus Spiraea L. The researched new taxa are resistant to drought, frost, pollutants and do not need special care, they only need pruning to ob-tain the desired shape and the observance of the appropriate technology throughout the growing season. The researched shrubs are particularly beautiful in early spring due to their abundant flowering and the attractive diverse colours of the flowers (white, pink, red, red-purple), the abundance of flowering and the long flowering period, but also in early summer – due to the colour of the foliage, the shape and size of the plants. It is recommended for use in landscaping, preferably in the foreground in small groups, together with oth-er species at the edges of stands and for hedges of different heights.

scholarly journals Ease of Access to An Alternative Food Source Enables Wallabies to Strip Bark in Tasmanian Pinus radiata Plantations

Forests ◽  
2020 ◽  
Vol 11 (4) ◽  
pp. 387 ◽  
Author(s):  
Anna H. Smith ◽  
David A. Ratkowsky ◽  
Timothy J. Wardlaw ◽  
Caroline L. Mohammed
Keyword(s):  
Pinus Radiata ◽  
Food Source ◽  
Floristic Composition ◽  
Radiata Pine ◽  
Early Summer ◽  
Bark Stripping ◽  
Site Factors ◽  
Generalist Herbivore ◽  
The Difference ◽  
Main Food Source

Bark stripping by the Bennett’s wallaby (Macropus rufogriseus (Desmarest) subsp. rufogriseus) from the lower stems of 3–6-year-old radiata pine (Pinus radiata D. Don) causes significant damage in Tasmanian plantations. The usual diet of this generalist herbivore is mainly grasses and broadleaved forbs. As the factors that attract a wallaby to supplement its diet by eating the bark of plantation pine trees are currently not elucidated, the present study aimed to determine how the incidence and severity of bark damage in 12 Tasmanian radiata pine plantations was influenced by various inter-site factors such as the floristic composition of the surrounding forest, and by various intra-site factors such as the height and circumference of individual trees, the number of branches in the first two whorls at the base of the tree, and their internode lengths. It was found that the greater the percentages of bare ground, bracken, and moss present in the five plots at each site, and the greater the percentage of grass, the wallaby’s main food source, the greater the likelihood of bark stripping. The difference between the mean minimum soil and air temperatures in spring, a driving force for carbohydrate production that occurs with tree growth in spring or early summer, was the only meteorological observation at the sites that was found to be significantly related to the extent of bark stripping.

scholarly journals Ease of Access to an Alternative Food Source Enables Wallabies to Strip Bark in Tasmanian Pinus Radiata Plantations

2020 ◽  
Author(s):  
Anna Smith ◽  
David Ratkowsky ◽  
Timothy Wardlaw ◽  
Caroline Mohammed
Keyword(s):  
Tree Growth ◽  
Pinus Radiata ◽  
Food Source ◽  
Floristic Composition ◽  
Radiata Pine ◽  
Early Summer ◽  
Bark Stripping ◽  
Site Factors ◽  
Generalist Herbivore ◽  
Ease Of Access

Bark stripping by the Bennett’s wallaby (Macropus rufogriseus rufogriseus) from the lower stems of 3–6-year-old radiata pine (Pinus radiata) causes significant damage in Tasmanian plantations. The usual diet of this generalist herbivore is mainly grasses and broadleaved forbs. As the factors that attract wallabies to supplement its diet by eating the bark of plantation pine trees are currently not elucidated, the present study aimed to determine how the incidence and severity of bark damage in 12 Tasmanian radiata pine plantations was influenced by various inter-site factors such as the floristic composition of the surrounding forest and by various intra-site factors such as the height and circumference of individual trees, the number of branches in the first two whorls at the base of the tree, and their internode lengths. Site differences in the observed percentage of bark stripping were found to be related to ‘ease of access’ variables such as bare ground, bracken, and moss, ‘hindrance to access’ variables such as rock and woody debris, and the percentage of grass, the wallaby’s main food source, present in the five plots at each site. The difference between the mean minimum soil and air temperatures in spring, a driving force for carbohydrate production that occurs with tree growth in spring or early summer, was the only meteorological observation at the sites that was found to be statistically significant. Nevertheless, there was no direct evidence that it was the movement of sugars in the phloem tissue accompanying tree growth which provided wallabies with a supplementary food source.

scholarly journals Conservation Implications of Shifting Gut Microbiomes in Captive-Reared Endangered Voles Intended for Reintroduction into the Wild

2018 ◽  
Vol 6 (3) ◽  
pp. 94 ◽  
Author(s):  
Nora Allan ◽  
Trina Knotts ◽  
Risa Pesapane ◽  
Jon Ramsey ◽  
Stephanie Castle ◽  
...  
Keyword(s):  
Bacterial Community ◽  
Food Source ◽  
Captive Breeding ◽  
Breeding Population ◽  
Microbial Composition ◽  
Multiple Generations ◽  
Conservation Implications ◽  
Functional Differences ◽  
Conservation Effort ◽  
Amargosa Vole

The Amargosa vole is a highly endangered rodent endemic to a small stretch of the Amargosa River basin in Inyo County, California. It specializes on a single, nutritionally marginal food source in nature. As part of a conservation effort to preserve the species, a captive breeding population was established to serve as an insurance colony and a source of individuals to release into the wild as restored habitat becomes available. The colony has successfully been maintained on commercial diets for multiple generations, but there are concerns that colony animals could lose gut microbes necessary to digest a wild diet. We analyzed feces from colony-reared and recently captured wild-born voles on various diets, and foregut contents from colony and wild voles. Unexpectedly, fecal microbial composition did not greatly differ despite drastically different diets and differences observed were mostly in low-abundance microbes. In contrast, colony vole foregut microbiomes were dominated by Allobaculum sp. while wild foreguts were dominated by Lactobacillus sp. If these bacterial community differences result in beneficial functional differences in digestion, then captive-reared Amargosa voles should be prepared prior to release into the wild to minimize or eliminate those differences to maximize their chance of success.

The decline of the Thick-billed Murre in Greeland

Polar Record ◽  
1976 ◽  
Vol 18 (114) ◽  
pp. 283-287 ◽  
Author(s):  
Peter Evans ◽  
George Waterston
Keyword(s):  
Food Source ◽  
Breeding Population ◽  
Conservative Estimate ◽  
Important Food ◽  
Uria Lomvia ◽  
The West ◽  
Important Food Source ◽  
Total Preservation ◽  
Brunnich’S Guillemot ◽  
Made In

The total breeding population of the Thick-billed Murre (Brünnich's Guillemot)Uria lomvia in west Greenland in 1951 was estimated to amount to two million pairs (Salomonsen, 1951), half of which inhabit the gigantic loomery at Kap Shackleton (Agparssuit) (Fig 1). Tuck (1960) considered this to be a conservative estimate, ‘and cannot concede that fewer than five million Thick-billed Murres inhabit the west coast of Greenland during the summer months’. The birds have long been considered an important food source by the inhabitants of the area. Rink (in Salomonsen, 1951, p 378) recorded a harvest of 70 000 birds as long ago as 1850; with the advent of modern shotguns and cheap ammunition the toll is now severe (Fig 2). As a result of shooting and disturbance population decreases have been recorded at various sites, but particularly those close to settlements (Table 1). In addition to the colonies listed in the table, a count was made in 1921 for the Sagdleq colony in the Umánaq district. An estimated 500 000 birds were recorded which, in 1949, had decreased to 250 000. In 1968 the Umánaq district legislated for total preservation of this colony for three years.

What catalysis needs from the electron microscopist

1988 ◽  
Vol 46 ◽  
pp. 694-695
Author(s):  
Alexis T. Bell
Keyword(s):  
Active Sites ◽  
Heterogeneous Catalysts ◽  
Catalyst Deactivation ◽  
Surface Composition ◽  
Internal Surface ◽  
Active Phase ◽  
Atomic Scale ◽  
Metal Catalyst ◽  
Internal Surface Area ◽  
Porous Support

Heterogeneous catalysts, used in industry for the production of fuels and chemicals, are microporous solids characterized by a high internal surface area. The catalyticly active sites may occur at the surface of the bulk solid or of small crystallites deposited on a porous support. An example of the former case would be a zeolite, and of the latter, a supported metal catalyst. Since the activity and selectivity of a catalyst are known to be a function of surface composition and structure, it is highly desirable to characterize catalyst surfaces with atomic scale resolution. Where the active phase is dispersed on a support, it is also important to know the dispersion of the deposited phase, as well as its structural and compositional uniformity, the latter characteristics being particularly important in the case of multicomponent catalysts. Knowledge of the pore size and shape is also important, since these can influence the transport of reactants and products through a catalyst and the dynamics of catalyst deactivation.

SEM Observations on the Germination of Euonymous Americanus

1985 ◽  
Vol 43 ◽  
pp. 508-509
Author(s):  
D.R. Hill ◽  
J.R. McCurry ◽  
L.P. Elliott ◽  
G. Howard
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Light Microscopy ◽  
Filter Paper ◽  
Room Temperature ◽  
Food Source ◽  
Environmental Chamber ◽  
Dormant Stage ◽  
Scanning Electron

Germination of Euonymous americanus in the laboratory has previously been unsuccessful. Ability to germinate Euonymous americanus. commonly known as the american strawberry bush, is important in that it represents a valuable food source for the white-tailed deer. Utilizing the knowledge that its seeds spend a period of time in the rumin fluid of deer during their dormant stage, we were successful in initiating germination. After a three month drying period, the seeds were placed in 25 ml of buffered rumin fluid, pH 8 at 40°C for 48 hrs anaerobically. They were then allowed to dry at room temperature for 24 hrs, placed on moistened filter paper and enclosed within an environmental chamber. Approximately four weeks later germination was detected and verified by scanning electron microscopy; light microscopy provided inadequate resolution. An important point to note in this procedure is that scarification, which was thought to be vital for germination, proved to be unnecessary for successful germination to occur. It is believed that germination was propagated by the secretion of enzymes or prescence of acids produced by microorganisms found in the rumin fluid since sterilized rumin failed to bring about germination.

Identification and Management of Clustered Pellitory (Parietaria praetermissa) in Citrus Groves

EDIS ◽  
2019 ◽  
Vol 2019 (5) ◽  
pp. 3
Author(s):  
Ramdas Kanissery ◽  
Biwek Gairhe ◽  
Brent Sellers ◽  
Steve Futch
Keyword(s):  
Drip Irrigation ◽  
Early Summer ◽  
Irrigation Systems ◽  
Spray Pattern ◽  
Citrus Groves ◽  
Low Volume ◽  
Florida Citrus ◽  
Heavy Infestation

In Florida, clustered pellitory is becoming a troublesome weed for citrus, especially from the winter through early summer. Inadequate management of this weed can result in its heavy infestation in tree rows and can interrupt the spray pattern of low-volume drip irrigation systems. This new 3-page publication of the UF/IFAS Horticultural Sciences Department will assist Florida citrus growers with proper identification of clustered pellitory and with adoption of adequate and timely strategies to manage this weed in their groves. Written by Ramdas Kanissery, Biwek Gairhe, Brent Sellers, and Steve Futch. https://edis.ifas.ufl.edu/hs1341

Sign in / Sign up

Export Citation Format

Share Document