Saturday, July 1, 2017

North Carolina Lilies

Part I: Nodding Lilies with Recurved Tepals


North Carolina is home to nine species of Lily, seven native and two introduced species1. This article will focus on the four species, Lilium lancifolium, L. michauxii, L. pryophilum, and L. superbum, with nodding flowers and strongly recurved tepals (Table 1, 2)( Photos 1).  


Table 1: Historic and Current Taxonomic Treatments

Common Name(s)              
         
Radford & Bell 2
(1968)        
E-Flora of North America 3(2002)
Weakley 1 (2015)
Tiger Lily
This species is not mentioned in Radford and Bell but was once named Lilium tigrinum Ker Gawler
No Data
Lilium lancifolium Thunberg

Carolina Lily
Lilium michauxii Poiret
Lilium michauxii Poiret
Lilium michauxii Poiret

Sandhills Bog Lily
This species is not mentioned in Radford and Bell but specimens were most likely misidentified as L. michauxii or L. superbum
Lilium pryophilum Skinner and Sorrie
Lilium pryophilum Skinner and Sorrie

Turk's-cap Lily
Lilium superbum L.
Lilium superbum L.

Lilium superbum L.





Photo 1. Turk's-cap Lily, Lilium superbum, flower showing the highly recurved tepals. Tepals are sepals and petals similar in appearance. In lilies there is an outer whorl of three sepals and an inner whorl of three petals thus, giving the illusion of six 'petals'. 


The Tiger Lily, Lilium lancifolium, is an introduced species from Asia. It has been grown as an ornamental for centuries and will sometimes escape and become naturalized in roadside ditches, old home places, and other disturbed areas. However, it is not very aggressive and is uncommon. Weakleyshows it occurring in the piedmont but, I know from personal experience it use to grow “wild” in Yancey County. My grandmother was born in Celo and as a young girl I remember going with her to visit relatives and pick blueberries. We would also visit the remains of the log cabin where she was born and dig plants to transplant to her yard in Morganton. She brought back sensitive fern, purple rose bushes, and tiger lilies. After her death I relocated the tiger lilies to my home where they still grow and bloom every year! Of the four species discussed in this article Tiger lilies are the easiest to identify. At first glance Tiger Lilies are very similar to Turk's-cap Lilies but, Tiger Lilies have alternate linear leaves with black bulblets in the axils of the upper leaves (see Photos 2, 3, 4,5). None of the other three species (in this article) have those two unique trait combinations.


Photo 2. Tiger Lily, Lilium lancifolium, note the black bulblets in the leaf axils. 


Photo 3: Note the alternate linear leaves on this Tiger 
Lily plant, unlike the whorled leaves found on the 
other species discussed in this article.


Photo 4: Tiger Lily tepals have nectary furrows and
large papillae whose function is unknown.

Photo  5: Close up of bulblets found in the leaf axils of Tiger Lilies.


Our three remaining, and native species, have many overlapping traits and some people have a more difficult time with their identification.


Table 2: Table of general characteristics of Lilium michauxii, L. pryophilum, and L. superbum. Note that shared traits between the species are in bold type.

Carolina Lily
 Lilium michauxii

Turk-cap’s Lily
Lilium superbum
Sandhills Bog Lily
Lilium pryophilum
May have 1-4 nodding flowers but usually just one flower per plant
May have up to 20 nodding flowers per plant

May have 1-7 nodding flowers per plant
Tepals strongly recurved
Tepals strongly recurved


Tepals strongly recurved
Flowers vary in color from yellow to orange to red-orange with brown-purple spots
Flowers vary in color from yellow to orange to red-orange with brown-purple spots
Flowers vary in color from yellow to orange to red-orange with brown-purple spots
Blooms July-mid-August
Blooms July-mid-August


Blooms July-mid-August
Leaves whorled or some leaves alternate,
2-4 whorls with 3-10 leaves per whorl
Leaves whorled or some leaves alternate,
6-24 whorls with up to 20 leaves per whorl
Leaves whorled or some leaves alternate,
1-12 whorls with 3-11 leaves per whorl
Leaves oblanceolate to obovate and widest towards the tip
Leaves are linear and up to 10x longer than wide, and widest in the middle
Leaves narrowly elliptic to oblong and widest towards the middle
No green star 
Has a green “star” on the inside base of the tepals
Has a green “star” on the inside base of the tepals

Mostly in mountains and piedmont in dryer habitats such as pine-oak forests, roadside slopes
Mostly  in mountains in moist habitats- meadows, balds, cove forests, roadside ditches  
Found only on coastal plain and very rare – swamps, seeps, pocosins,  and bogs


Turk-cap’s Lily, Lilium superbum, is the largest and most common lily in the eastern United States3. Compared to the other two species (L. michauxii and L. pryophilum) everything about this plant screams “bigger and more”! The plants can be quite impressive with heights up to 2.4 meters (8 feet for the metrically challenged) and up to 20 flowers per inflorescence (Photo 6, 7, 8, 9, 10). It has numerous nodes (6-24) with as many as 20 leaves per whorl. The linear leaves are up to 10x longer than wide (7-23 cm long) with drooping tips (Photo 11) . Turk’s-cap lily can grow in a large variety of habitats ranging from moist meadows, balds, roadsides, rich cove forests, swamps, and coastal bogs. According to Weakley1, it is very common in our mountains and rare in the piedmont and coastal plain. I commonly see it along the Blue Ridge Parkway during the months of July and August. 



Photo 6: Turk's-cap Lily demonstrating the numerous flowers in
one inflorescence. Some plants may have up to 20 flowers.


Photo 7: Turk's-cap Lilies can vary greatly in color,
this specimen is a beautiful golden yellow.


Photo 8: This Turk's-cap Lily flower has a deep orange-red color.


Photo 9: This specimen of Turk's Cap Lily
shows the more typical orange color. Note the
'green star' pattern at the base of the tepals.


Photo 10: Close up of Turk's-cap Lily anthers. 
Photo 11:  Turk's-cap Lily with  whorled linear leaves.

Carolina Lily, Lilium michauxii, is the official wildflower of North Carolina. Many people often get the Turk’s-cap Lily and Carolina Lily confused. This may be because they bloom at the same time and have very similar flowers. However, where the Turk’s-cap Lily is “bigger and more” the Carolina Lily is “smaller and less”. The Carolina Lily (Photos 12, 13, 14, 15) is .6 – 1.2 meters (2-4 feet) tall with one to four flowers. I rarely see plants with more than one flower (Photo 14). It has 2-4 whorls with 3 –10 leaves per whorl. The leaves are 3-11 cm long and widest towards the tip (Image 1). One thing I noticed is that the leaves have a fleshy texture unlike the thinner leaves of the Turk's-cap and Sandhills Bog Lilies. Also, the Carolina Lily is the only fragrant lily in the eastern U.S. The species is commonly found in the mountain and piedmont and less commonly along the coast. It grows mainly in pine-oak forests along the upper dryer slopes and ridges. I often see Carolina Lily blooming from July to August along roadside banks of forest service roads.

Photo 12:Carolina Lily, Lilium michauxii,
from the South Mountains Game Lands. 


Photo 13: This Carolina Lily plant was growing within 3 feet of the plant in photo 12, note the large difference in flower color. Both of these specimens where growing on a dry exposed roadside bank near a pine-oak forest.

Photo 14: These two Carolina Lilies show typical traits of  the species;
the plants are relatively short and have only one flower.

Image 1: Carolina Lily is on the left, notice the whorled obovate leaves. This art work is public domain.

Photo 15: Whorled leaves of Carolina Lily, note
that the leaves are widest towards the tip.

I have noticed that many people try to distinguish between Carolina and Turk’s-cap Lilies by looking at the base of the tepals for a ‘green star’. Supposedly Turk’s-cap Lilies have the green star and Carolina Lilies do not. But I have seen Carolina Lilies with very green bases so I am not sure how dependable this trait is (Photo 16, 17, 18).


Photo 16: Turk's-cap Lily with a distinct
green star pattern at the base of the tepals.

Photo  17: This is a close-up of  a Carolina Lily, note that there is
no green star pattern present at the base of the tepals.


Photo 18: This is also a Carolina Lily with a definite
green star pattern at the base of the tepals.



In the past the Sandhills Bog Lily, Lilium pyrophilum, has been identified as L. iridollae, L. superbum, and L. michauxii.  Finally, in 2002 it was recognized by Skinner & Sorrie as a distinct and new species. It is a coastal endemic found only in 16 counties within Virginia, N.C., and South Carolina4. It is federally endangered and found sporadically and in small populations growing in bogs, pocosins, seeps, and swamps. The Sandhills Bog Lily (Photo 19) is about 1.2 meters (4 ft.) in height with 1-7 flowers per plant. Plants may have 1-12 whorls of leaves with 3-11 leaves per whorl. The elliptic leaves are 2-16 cm long and widest in the middle. Compared to the Carolina and Turk’s-cap Lilies, the Sandhills Bog Lily is intermediate in many traits; height, number of leaf whorls, number of leaves per whorl, and number of flowers. This may be why many herbarium specimens where originally misidentified as either Turk’s-cap or Carolina Lily. The issue is further complicated by several issues. One, the Sandhills Bog Lily will hybridize with the Carolina Lily and produce hybrid plants of intermediate traits3. Two, apparently the Turk's-cap Lilies along the coast are different enough from their mountain populations that some botanists believe they may warrant a separate species status1.



Photo 19: Note that the Sandhills Bog Lily has a green star pattern similar to Turk's-cap Lilies. This photo is public domain, all other photos
in this article, unless otherwise denoted, are property of Tracie Jeffries. 

In theory, identification of these three species seems fairly clear cut if you consider both morphology and habitat together. For Turk’s-cap Lily think ‘big’. If you are in the mountains and come across a tall lily with numerous, pendulant orange-red flowers, recurved petals, in a moist habitat, it is most likely Lilium superbum. For Carolina Lily think ‘small’. In the mountains and piedmont, if you see a shorter lily with one to a few pendulant orange-red flowers, with recurved petals, in a dry habitat, it is most likely Lilium michauxii. For the Sandhills Bog Lily think ‘intermediate’. Lily plants in a wet remote area on the coastal plain, that have a handful of pendulant orange-red flowers, with recurved petals, is most likely Lilium pryophilum.  In practice however, due to many overlapping traits and hybridization, it is still difficult to sometimes achieve a positive identification. But, I hope this article has clarified some issues and I wish you happy wildflower hunting!


Resources:
1. Weakley, Alan S. Flora of the Southern and Mid-Atlantic states. Chapel Hill, NC: University of North Carolina Herbarium, North Carolina Botanical Garden, University of North Carolina, Chapel Hill, 2015. Print.

2. Radford, Albert Ernest, Harry E. Ahles, and Clyde Ritchie Bell. Manual of the vascular flora of the Carolinas. Chapel Hill, NC: University of North Carolina Press, 1983. Print.

3. " Liliaceae." Lilium in Flora of North America @ efloras.org. N.p., n.d. Web. 01 July 2017. <http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=118558>.

4. Skinner, Mark W., and Bruce A. Sorrie. "Conservation and Ecology of Lilium pyrophilum, a New Species of Liliaceae from the Sandhills Region of the Carolinas and Virginia, U.S.A." Novon 12.1 (2002): 94. Web.