The name "tiger lily" is a common name for several different kinds of lilies and one daylily or hemerocallis.
Hemerocallis fulva is an orange daylily commonly found along roadside ditches or around old buildings. It is rock hardy and blooms with a massive display of orange blossoms in mid-summer. However, it is not a lily.
Lilium columbianum is a native lily, the flowers are more yellow than orange, facing downward with orange spots. It is a western native, found in part shade areas or sheltered from the sun in long grasses.
Lilium lancifolium used to be called Lilium tigridium and is a bright orange lily with black spots, facing downward and is grown in sunny gardens.
This plant doesn't produce seed but small tiny bulblets along the stem of the plant. These can be collected and sown in the garden.
Lilium philadelphicum or the wood lily is an orange lily native to North America. It is quite distinctive because of the way the petals narrow at the base. It is found in woodlands and is a delightful shade plant.
Although not of the lily family the name is also sometimes applied to flowers of the genus Tigridia. These are quite tender bulbs native to Mexico.
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