In the next month or two, we will see how easily newly introduced seed cases are able to establish local epidemics outside the Chinese mainland.
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Many of the seed cases are decorative. Some are quite large. Many have unusual shapes or they are rough with "bubbly" warts or tubercules which add interest and texture to a garden. Some Hakeas have long racemes up to 20 centimetres long.
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The leaves open only after the flowers have bloomed and wilted; they are narrow oval, 2–6 cm long and 1–2 cm broad. When not in flower, it can still be identified by its peculiar, orange-brown seed cases, 1–1.2 cm long.
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The brimstone canary is less gregarious than other canaries. It tends to be found singly or in pairs, or occasionally in small groups, and is a common visitor to gardens. It feeds on fruit, seeds, flowers and shoots. Hard seed cases are cracked with the stout bill.
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At maturity the seed cases turn blackish and fall to the ground A. holocarpa is very tolerant of saline conditions and can be used to help colonise saline waste dumps. Salts are extruded through the plants' vesiculated hairs to prevent salt reaching toxic levels.Mozafar, A. and Goodin, l.R. 1970.
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Its flowers, typically white with yellow centers, grow from numerous fairly rigid stems. Plants have blue-green leaves and grow to 45 to 100 cm (18 to 39 in) in height. The plant is economically important as a natural source of an insecticide called "pyrethrum." The flowers are pulverized and the active components, called pyrethrins, contained in the seed cases, are extracted and sold in the form of an oleoresin.
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Chrysanthemic acid is an organic compound that is related to a variety of natural and synthetic insecticides. It is related to the pyrethrin I and II, as well as the pyrethroids. One of the four stereoisomers, (1R,3R)- or (+)-trans-chrysanthemic acid (pictured), is the acid part of the ester pyrethrin I, which occurs naturally in the seed cases of Chrysanthemum cinerariaefolium. Many synthetic pyrethroids, for example the allethrins, are esters of all four stereoisomers.
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The pyrethrins occur in the seed cases of the perennial plant pyrethrum (Chrysanthemum cinerariaefolium), which has long been grown commercially to supply the insecticide. Pyrethrins have been used as an insecticide for thousands of years. It is believed that the Chinese crushed chrysanthemum plants and used the powder as an insecticide as early as 1000 BC. It was widely known that the Chou Dynasty in China widely used pyrethrin for its insecticide properties."History." Pyrethrum Nature's Insecticide.
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When they approach the midpoint they notice that the tribal markings are different; upon reaching it, they are attacked by members of the Dalton-Quinn tribe who live at the other end of the tree. During the battle a massive tremor splits the tree in half, causing the in tuft to fall farther toward Voy (killing its inhabitants) and allowing the out tuft to find a new equilibrium that is closer to the Smoke Ring's median. The seven surviving members of the Quinn Tribe and one of the attackers jump clear of the shattered tree and are left adrift in the sky with only a few "jet pods" (high pressure seed cases that provide a temporary thrust when opened) as their only method of propulsion. Before dying of thirst, they hook a passing "moby" (a flying whale-like creature) which takes them to a "jungle," which is a floating mass of plant life.
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In New Zealand, there are no human remains, artefacts or structures which are confidently dated to earlier than the Kaharoa Tephra, a layer of volcanic debris deposited by the Mount Tarawera eruption around 1314 CE. The 1999 dating of some kiore (Polynesian rat) bones to as early as 10 CE was later found to be an error. New samples of rat bone (and also of rat- gnawed shells and woody seed cases) gave dates later than the Tarawera eruption except for three which dated to a decade or so before the eruption. Pollen evidence of widespread forest fires a decade or two before the eruption has led some scientists to speculate that humans may have lit them, in which case the first settlement date could have been somewhere in the period 1280–1320 CE which is now a widely quoted date. However, the most recent synthesis of archaeological and genetic evidence concludes that, whether or not some settlers arrived before the Tarawera eruption, the main settlement period was in the decades after it, somewhere between 1320 and 1350 CE, possibly involving a coordinated mass migration.
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