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Common Dandelion Is An Introduced How Dandelions Breed…You’d Never Guess! Tuft of hairs () carries fruit on the Common dandelion is an introduced in . In the With their colourful and abundant and , dandelions Needle-like beak channel a lot of energy into attracting pollinating . Yet mid-1600s, European settlers brought the common dandelion supports pappus -head or "blowball" amazingly, dandelions do not need to be pollinated to set seed. (scientific name, officinale) to eastern America and - opens on dry weather to release cultivated it in their gardens for food and medicine. Since then it has Achene with spines - stands tall above nearby to catch wind spread across the continent as a weed. that help it stick to soil - with many heads of 150-200 fruits each, a Instead the female parts of the flowers develop on their own, plant easily produces 1000-2000 seeds/year through a process called . Because of this, the offspring of - tiny, seed-like fruit (achene) is light enough to A weed is a plant that grows where it is not wanted, often colonizing Floret be carried by a feathery parachute each plant are genetically identical to their parent. If each new plant the open, disturbed areas created by human activity. Gardens, produces 1000 offspring and each of these produces 1000 and so on, fields, pastures, waysides and waste places, all provide excellent Ribbon-like corolla it doesn't take long to generate 1,000,000s of identical plants. dandelion habitat. (ligule) of 5 joined attracts attention Groups of genetically identical organisms are called clones. With Stigma (female part) excellent and clones of well-adapted plants, common catches pollen dandelion has colonized disturbed habitats throughout the world. Native Dandelions Cylinder of joined anthers (male part) produces pollen Native plants are that occur naturally in an Cup of green (involucre) Developing pappus - protects buds, then opens as Dandelions & Humans: Travelling Companions area. There are several native dandelions in North and achene the flowers mature America, but only one of these, a small alpine species - protects developing fruits, then folds called northern dandelion (Taraxacum ceratophorum), back to expose fluffy seed heads Dandelions originated in temperate and subarctic before the last grows in Alberta. Ice Age. They were adapted to disturbed habitats on shores, mountain Large, fragrant flower head slopes and steppes, so after the Ice Age their populations spread rapidly - attracts attention of insects (and gardeners) over the vast exposed landscapes left by retreating glaciers. - provides abundant early pollen and nectar Hollow elongating stalks - raise flowers above to attract insects Flower Power - lift seeds even higher, to catch the wind. As the human population grew, people created similar disturbed habitats by burning and clearing for hunting and agriculture, and dandelions Dandelions belong to the Aster Family (scientific name Abundant, bitter, white juice (latex) continued to spread. Soon humans started to use dandelions. or Compositae). In this family, each “flower” - deters insects and other animals from munching on plants is really a head of tiny flowers (florets) crowded together - kills disease organisms Eventually, both Eurasians (human and dandelion!) moved on to for show. - plugs wounds colonize other temperate regions. Today, both species thrive in man- modified habitats around the world. Dandelion florets reflect ultraviolet light which attracts certain insects, including , to feed on the pollen and nectar. Many of these insects are also important arrangement (rosette) - helps leaves catch maximum sun of other plants, including crops. - shades or smothers nearby plants Dandelions & Humans: Living Together Toothed, green leaves - produce food for the plant by photosynthesis Because of their love affair with human habitats, dandelions - adapt to growing conditions (e.g. small and flat- lying on sunny lawns; large and upright among tall are clearly here to stay. So how can we learn to live happily plants and in shady sites) with this biological superstar? Herbicides may temporarily Tough taproot reduce dandelion numbers, but they can also poison people - anchors plant securely and other creatures and pollute water - a huge environmental - reaches deep for water and nutrients - stores food over winter so the plant has a cost. Instead, let’s reduce dandelion habitat by maintaining head-start next spring healthy lawns and using alternative landscaping. If we learn - can produce new plants from fragments to “dig” our dandelions, we should be able to enjoy the few - contracts and pulls growing point to or below ground level, where it is difficult to cut that remain.

Linda Kershaw, Patsy Cotterill, Sarah Wilkinson © 2002 Sponsored by the Alberta Native Plant Council