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You may think that if a plant has an underground storage organ, that remains there year after year, pushing through the soil to flower such as lilies, crocus, cyclamen, erythronium, iris, daffodils lily of the valley and dahlias, then it must be a bulb.
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· Bulbs – Modified stems, where the overlapping leaves have been adapted to swell and store food and nutrients for the plant eg. Lilies & Daffodils
· Corms –Stubby modified stems, which are vertically orientated eg. Crocus & Erythonium
· Tubers - Short, thickened regions of stem or root, which are used to store food for later growth eg. Cyclamen (stem) & Dahlia (root)
· Rhizomes - Modified plant stems that grow near the soil surface and producing the upward shoot and downward root system eg. iris and lily of the valley.
Plants often modify themselves to ensure survival, and all these modifications occur to survive the British climate - when temperatures drop below freezing, the plant does not have to produce food using photosynthesis – it has plenty stored already for the next year.
· Rhizomes - Modified plant stems that grow near the soil surface and producing the upward shoot and downward root system eg. iris and lily of the valley.
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