Pteridium esculentum, commonly known as Austral bracken or simply bracken, is a species of the bracken genus native to a number of countries in the Southern Hemisphere. Esculentum means edible.
First described as Pteris esculenta by German botanist Georg Forster in 1786, it gained its current binomial name in 1908. The Eora people of the Sydney region knew it as gurgi.
P. esculentum grows from creeping rhizomes, which are covered with reddish hair. From them arise single large roughly triangular fronds, which grow to 0.5–2 metres (1 ft 8 in–6 ft 7 in) tall. The fronds are stiff with a brown stripe.
It is found in all states of Australia apart from the Northern Territory, as well as New Zealand, Norfolk Island, Malaysia, Polynesia, and New Caledonia. Within Victoria it is widespread and common to altitudes of 1,000 metres (3,300 ft).[5] In New South Wales, it occurs in across central, eastern and southern parts of the state. It can also be weedy and invade disturbed areas.[4] In Western Australia, it grows near the southern and western coastlines, as far north as Geraldton.
Like its northern hemisphere relatives, Pteridium esculentum is very quick to colonise disturbed areas and can outcompete other plants to form a dense understorey. It is often treated as a weed. It does create a more humid sheltered microclimate under its leaves and is food for a variety of native insects.[7] Two species of fruit fly (Drosophila) were recorded in a field study near Sydney, Another study near Sydney yielded 17 herbivorous arthropods (15 insects and two mites), notable for the lack of Hymenoptera (ants, bees and wasps) and Coleoptera (beetles).
Asclepias syriaca, commonly called common milkweed, butterfly flower, silkweed, silky swallow-wort, and Virginia silkweed, is a species of flowering plant. It is in the genus Asclepias, the milkweeds. This species is native to southern Canada and of much of the conterminous eastern U.S., east of the Rocky Mountains, excluding the drier parts of the prairies. It grows in sandy soils and other kinds of soils in sunny areas. It was one of the earliest North American species described in Cornut's 1635 work Canadensium Plantarum Historia. The specific name was reused by Linnaeus due to Cornut's confusion with a species from Asia Minor.
Common milkweed is a clonal perennial herb growing up to 2.6 m tall. Its ramets grow from rhizomes. All parts of common milkweed plants produce white latex when broken. The simple leaves are opposite or sometimes whorled; broad ovate-lanceolate; up to 25 cm long and 12 cm broad, usually with entire, undulate margins and reddish main veins. They have very short petioles and velvety undersides.
The highly fragrant, nectariferous flowers vary from white (rarely) through pinkish and purplish and occur in umbellate cymes. Individual flowers are about 1 cm in diameter, each with five cornate hoods and five pollinia. The seeds, each with long, white flossy hairs, occur in large follicles. Fruit production from selfing is rare. In three study plots, outcrossed flowers had an average of about 11% fruit set.
Ecology
Many kinds of insects visit A. syriaca flowers, and some kinds pollinate them, including Apis mellifera (Western honey bees) and Bombus spp. (bumble bees).[3][4] In the U.S. Mid-Atlantic Region, the introduced A. mellifera was the most effective and most important diurnal pollinator with regard to both pollen removal and pollen deposition.[5] However, when considering the self-incompatibility of A. syriaca, A. mellifera was not the most important pollinator because of its high self-pollination rate compared to Bombus spp. Additionally, the rate of self-pollination increased more rapidly with the number of flowers per inflorescence in A. mellifera than in native Bombus spp.
Many insect species feed on common milkweed, including the red milkweed beetle (Tetraopes tetrophtalmus), large milkweed bug (Oncopeltus fasciatus), small milkweed bug (Lygaeus kalmii), milkweed aphid (Aphis nerii), milkweed leaf beetle (Labidomera clivicollis), milkweed stem weevil (Rhyssomatus lineaticollis), milkweed tiger moth (Euchaetes egle) and monarch butterfly (Danaus plexippus). Monarch larvae consume only milkweeds, and monarch populations may decline when milkweeds are eliminated with herbicides.[6]
Efforts to increase monarch butterfly populations by establishing butterfly gardens require particular attention to the butterfly's food preferences and population cycles, as well to the conditions needed to propagate milkweed. For example, in the Washington, D.C., area and in the northeastern United States, monarchs prefer to reproduce on Asclepias syriaca, especially on young, soft leaves.[7] Common milkweed new, tender leaves are preferred monarch oviposition sites and larval food.[7] In the Washington, D.C., area, one can have such leaves in July, August, and early September during the main oviposition period in three ways. First, one can grow seedlings.[7] Second, one can cut large shoots to about half their height in June and July before or after they bloom.[7] Third, one can cut large shoots to the ground in June and July. Cut plants often produce new shoots from their rhizomes.[7] It is advisable to let some large, mature shoots remain in summer and fall because large monarch larvae, milkweed tiger moth larvae, and other native species feed on mature leaves. Milkweed bugs commonly feed on follicles. Monarch larvae can consume small seedlings to the ground. To save seedlings, one can transfer larvae from seedlings to larger shoots.
Deforestation due to European settlement may have expanded the range and density of common milkweed. This plant can become invasive; it is naturalized in several areas outside of its native range, including Oregon and parts of Europe. However, recently in the United States, milkweed populations have diminished dramatically due to factors such as development and the use of herbicides, which has played a significant part in the monarch butterfly's dramatic population decline.
Cupressus cashmeriana (Bhutan cypress, Kashmir cypress, weeping cypress; Dzongkha language: Tsenden) is a species of cypress native to the eastern Himalaya in Bhutan and adjacent areas of Arunachal Pradesh in northeastern India. It is also introduced in China and Nepal. It grows at moderately high altitudes of 1,250–2,800 metres (4,100–9,190 ft).
Cupressus cashmeriana is a medium-sized to large coniferous tree growing 20–45 metres (66–148 ft) tall, rarely much more, with a trunk up to 3 metres (9.8 ft) diameter. The foliage grows in strongly pendulous sprays of blue-green, very slender, flattened shoots. The leaves are scale-like, 1–2 mm long, up to 5 mm long on strong lead shoots; young trees up to about 5 years old have juvenile foliage with soft needle-like leaves 3–8 mm long.
The seed cones are ovoid, 10–21 mm long and 10–19 mm broad, with 8–12 scales, dark green, maturing dark brown about 24 months after pollination. The cones open at maturity to shed the seed. The pollen cones are 3–5 mm long, and release pollen in early spring.
A tree of 95 metres (312 ft) tall has recently been reported, but the measurements await verification.
Meconopsis autumnalis, the Nepalese Autumn Poppy, is a yellow-flowered Himalayan poppy belonging to series Robustae, and is endemic to the Ganesh Himal range of central Nepal, where it was discovered in 2008 on a research expedition from the University of Aberdeen. In addition to several morphological features, the species is characterised by its late flowering period (as reflected in the specific etymology), which has more than likely resulted in a barrier to gene flow and subsequent evolutionary divergence from the closely related and sympatric species Meconopsis paniculata.
Specimens of M. autumnalis had twice previously been collected, by famous plant hunter J. D. A. Stainton on his 1962 expedition with S. A. Bowes Lyon to central Nepal, and on the Flora of Ganesh Himal expedition undertaken by the University of Tokyo in 1994. However, despite recognition as to the novelty of the plant implicated in Stainon's fieldnotes accompanying the species paratype (where it was described as 'easily distinguishable' from M. paniculata), it was not until new collections and field observations in 2008 that the true status of the plant as a new species was definitely realised. It was formally described in 2011.
M. autumnalis grows in sub-alpine habitat commonly along stream margins, grassy alpine slopes or at edges and openings of Abies forest. Commonly associated herbaceous species include Rumex, Arisaema, Stellaria, Nepeta, Persicaria, Aster, Swertia, as well as dwarf shrubs such as Berberis, Rhododendron and Juniperus. The species ranges in elevation from 3300–4200 m, favouring stony, humus-rich soils. Similar to Meconopsis manasluensis and other Meconopsis of Nepal, the species appears to exhibit a very limited geographic distribution, thus necessitating more in-depth conservation assessment. Flowering occurs in late July to September.
Rheum nobile, the Noble rhubarb or Sikkim rhubarb is a giant herbaceous plant native to the Himalaya, from northeastern Afghanistan, east through northern Pakistan and India, Nepal, Sikkim (in India), Bhutan, and Tibet to Myanmar, occurring in the alpine zone at 4000–4800 m altitude.
It is an extraordinary species of rhubarb (genus Rheum). At 1–2 m tall, R. nobile towers above all the shrubs and low herbs in its habitat, and it is visible across valleys a mile away.
R. nobile is often called a glasshouse plant because of its outer curtain of translucent bracts which pass visible light, creating a greenhouse effect, while blocking ultraviolet radiation. These are important defenses against the increased UV-B exposure and extreme cold in its high altitude range.
Mesembryanthemum crystallinum is a prostrate succulent plant native to Africa, Sinai and southern Europe, and naturalized in North America, South America and Australia. The plant is covered with large, glistening bladder cells or water vesicles, reflected in its common names of common ice plant, crystalline ice plant or ice plant. The bladder cells are enlarged epidermal cells. The main function of these bladder cells is to reserve water. It can be annual, biennial or perennial, but its life cycle is usually completed within several months, depending on environmental conditions.
Mesembryanthemum crystallinum is found on a wide range of soil types, from well-drained sandy soils (including sand dunes), to loamy and clay soils. It can tolerate nutritionally poor or saline soils. As with many introduced species it also grows in disturbed sites such as roadsides, rubbish dumps and homestead yards.
The plant usually uses C3 carbon fixation, but when it becomes water- or salt-stressed, it is able to switch to Crassulacean acid metabolism. Like many salt-tolerant plants, M. crystallinum accumulates salt throughout its life, in a gradient from the roots to the shoots, with the highest concentration stored in epidermal bladder cells. The salt is released by leaching once the plant dies. This results in a detrimental osmotic environment preventing the growth of other, non-salt-tolerant species while allowing M. crystallinum seeds to germinate.
Mesembryanthemum crystallinum flowers from spring to early summer . Flowers open in the morning and close at night, and are insect pollinated.
In M. crystallinum, the number of seeds produced depends on whether CAM has been activated (C3 metabolism is more efficient) and the size the plant has grown to in its juvenile growth phase. During seed production, older portions of the plant progressively die off and dry out. The developing seed capsules continue to sequester salt and produce viable seeds. Seeds at the top of the capsule generally germinate immediately on imbibation while seeds at the base may remain dormant for longer than four weeks.
Pteridium esculentum, commonly known as Austral bracken or simply bracken, is a species of the bracken genus native to a number of countries in the Southern Hemisphere. Esculentum means edible.
P. esculentum grows from creeping rhizomes, which are covered with reddish hair. From them arise single large roughly triangular fronds, which grow to 0.5–2 metres (1 ft 8 in–6 ft 7 in) tall. The fronds are stiff with a brown stripe.
