Wood Lily is a highly variable plant with many variations in leaf size, height, number of leaf whorls, color of petals and sepals and the size of the seed capsule. At one time two varieties were accepted due to this variation, but all are now considered to be variations not sufficient to be classed as separate varieties.
Wood Lily is an erect perennial lily growing on unbranched stems that are usually smooth, green, rounded in cross section and reaching to almost 4 feet high, but the plants found in sunny upland locations in the western half of the species range will be shorter.
Leaves are usually alternate on the stem, not dense, with at least one whorl of 3 to 11 leaves at the top of the stem. Leaves are of narrow elliptic to linear shape, stalkless, and parallel veins. Tips taper to a rounded point. Both blade surfaces are without hair although the underside is paler in color. They can be 3.5 to 18x longer than wide and are held horizontally, with the leaves of the upper whorl upward ascending, and then drooping at the pointed tips.
The inflorescence consists of 1 to 3 flowers, in an umbel form branching from the top of the stem.
The flowers are held erect, not pendant and are not fragrant. The 3 sepals and 3 petals look similar and as the flower opens they flare outward and recurve slightly but not completely as in L. superbum or L. michiganense. The color can vary widely from reddish-orange, reddish-magenta, pure reds or pale orange. Their bases are distinctly clawed with nectar guides above the claws colored lighter and spotted with maroon. The sepals have obtuse to acute tips and are slightly longer (4.9 to 8.2 cm) than the petals (4.5 to 7.7 cm), but not as wide. There are 6 stamens, strongly exserted, with filaments the same color as the petals and maroon anthers. The stamens surround the long style near the base and then diverge only slighty, with anthers held erect. The perianth of the flower is in a wide bell-shape.
Seed: Wood Lily forms a 3-chambered capsule containing hundreds of wafer thin disc shaped seeds. The capsule is 3 to 4.8 x longer than wide, the longest capsule of any North American Lily. The seeds require a warm moist period followed by a cold moist period of 60 to 90 days each for germination.
Habitat: Wood Lily has the widest range of any North American Lily. It is found from the high mountain meadows, to the prairie grasslands and into the Appalachians of the east. It grows from a scaly bulb that is longer than wide.
Names: An older name, now considered a synonym is Lilium umbellatum. The genus Lilium is derived from the Greek word 'lirion' for lily. The species name philadelphicum, means 'of Philadelphia' the type location. The author name for the plant classification - 'L.', refers to Carl Linnaeus (1707-1778), Swedish botanist and the developer of the binomial nomenclature of modern taxonomy.
Other comparisons: The wide variation in the species eventually led to just two varieties - var. andinum, found mostly in the western region as far east as Ohio and var. philadelphicum of the eastern region. Flora of North America (Ref. #W7) has a good write-up on these differences and what led to them deciding to not recognize varieties.
One other species is very similar to L. philadelphicum and that is the Pine Lily, L. catesbaei of the Southeastern United States. In that species the sepals are longer (8.2 to 12 cm) and have very acute tips. The leaves are widely scattered without whorls. See diagram below.
Above: 1st photo - an historic photo from a Kodachrome taken in the Garden by Martha Crone on June 22, 1949. Note the stamens just slightly diverging from around the style and the maroon spots in the yellow areas near the nectar guides. The inflorescence can be a single or a group of 2 or 3 long stalked flowers at the top of the stem. 2nd photo - the sepals are slightly longer than the petals and there is a whorl of leaves at the top of stem.
Below: 1st photo - The entire perianth is a widely spreading bell shape with petals and sepals having a distinctly clawed base. Drawing: Comparison to the closest look-alike, the Pine Lily, L. catesbaei. Note that species has no leaf whorl, distinctly longer petals and sepals and more acute tips. Drawing courtesy and ©Flora of North America.
Below: 1st photo - The leaves are widely scattered below the whorl, narrow. 2nd photo - the leaf underside shows the vein pattern and smooth margins.
Notes: Wood Lily is not indigenous to the Garden itself but was brought in many times by Eloise Butler beginning in 1909 with plants from Bear Hill, MA. Then beginning in 1913, she planted it in each 16 of the next 20 years. In 1932 she reported planting Lilium umbellatum near her new Mallard Pool but that name is today considered a synonym for L. philadelphicum. Martha Crone was also an active planter beginning in 1945, and then in 8 of the next 13 years. Susan Wilkins added plants in 2012.
Wood Lily is the most widely distributed native lily in North America. It is found in the southern parts of the Canadian Provinces of Alberta, Saskatchewan, Manitoba, Ontario and Quebec, and in the mountains of British Columbia. In the U.S. it ranges from the Rockies, into the grasslands of the prairies and eastward into the Appalachians to the east coast. In Minnesota it is widespread with only 18 counties not reporting in on the DNR plant surveys - most of those in the south west, south central part of the state.
Only two lily species are native to Minnesota: L. michiganense, Michigan Lily; and L. philadelphicum, Wood Lily.
References: Plant characteristics are generally from sources 1A, 32, W2, W3, W7 & W8 plus others as specifically applied. Distribution principally from W1, W2 and 28C. Planting history generally from 1, 4 & 4a. Other sources by specific reference. See Reference List for details.
Identification booklet for most of the flowering forbs and small flowering shrubs of the Eloise Butler Wildflower Garden. Details Here.
Friends of the Wild Flower Garden, Inc. Text and photos are by G. D. Bebeau unless otherwise credited. "www.friendsofthewildflowergarden.org"