Lycopodium: Growth Form, Morphology, and Sustainability of a Non-Timber Forest Product

NTFP Conference Proceedings

Lycopodium: Growth Form, Morphology, and Sustainability of a Non-timber Forest Product

Elizabeth A. Nauertz1 and John C. Zasada2

Abstract.—Several species of Lycopodium or clubmoss belong in the category of non-timber forest products and are often gathered for a variety of traditional uses. It is important to evaluate baseline information for these species, such as abundance and frequency of occurrence, before making any management decision. In addition, under- standing the biology of the Lycopodium group as a whole, including growth form and morphology, may enable us to make better decisions about forest management practices used and harvesting quotas allowed for sustaining these species.

INTRODUCTION SPECIES DESCRIPTIONS AND USES

Several Lycopodium or clubmoss species are Following is a brief description of each of the extensively collected as non-timber forest six Lycopodium species discussed in this paper. products and are marketed to industries for The descriptions are compiled from personal production of seasonal and traditional decora- observations, as well as information referenced tions and for floral and horticulture uses. In from the literature (Cody and Britton 1989; addition, medicinal (Aboriginal and homeo- Flora of North America 1993; Johnson et al. pathic), native folklore, and theatrical uses 1995; Lellinger 1985; Meeker et al. 1993; exist for various Lycopodium species (Johnson Primack 1973; Turner et al. 1983; Ullman et al. 1995; Shakhashiri 1983; Ullman 1992, 1992, 1997). 1997). Lycopodium species are considered to be fern-allies. In temperate forests they are vascu- Lycopodium species vary in growth form and lar, terrestrial, evergreen, perennial, rhizoma- morphology. The mature aerial stems of a plant tous, and clonal in nature. This group of photosynthesize. They may be either non- species has been around a long time, with branching or treelike in form. When mature, ancestors that date back to the Tertiary period the aerial stems often have cones (strobili) or (Lellinger 1985). Few studies have been done to sporangia that produce the spores necessary determine how these species can be regener- for sexual reproduction. Spores mature and are ated and how fast they recover after harvesting released in the late fall, even as late as Novem- (Matula 1995, Primack 1973). Although some ber. In general, Lycopodium aerial stems reach of the Lycopodium species are common in maturity and begin to produce spores at from 4 northern hardwood forests, the impacts of to 6 years of age, depending on the species and forest management practices on populations of local growing conditions. Lycopodium species these species are not well understood. have either aboveground or belowground running rhizomes or lateral branches. The 1Ecologist, U.S. Department of Agriculture, rhizomes have the ability to produce adventi- Forest Service, North Central Research Station, tious roots and are used for photosynthate, 410 MacInnes Drive, Houghton, Michigan 49931, water, and nutrient transport. The rhizomatous USA; Phone: 906-482-6303; e-mail: nature of these species may add to the photo- [email protected]. synthesis capacity of the plant as a whole and 2Project Leader and Research Forester, U.S. may affect the plant’s ability to get around Department of Agriculture, Forest Service, North vegetatively. A typical Lycopodium patch can Central Research Station, 1831 Highway 169 E., have multiple-aged lateral branches or rhi- Grand Rapids, Minnesota 55744, USA; Phone: zomes, and each rhizome may have ramets that 218-326-7109; e-mail: [email protected]. vary in age from 1 to 6 years. In general, the 110 bigger and more branching the patch, the older the same manner as the ground cedar. Tradi- it is. tional Aboriginal and homeopathic remedies are concocted from the dried plant parts of this The aerial stems of Lycopodium dendroideum species. L. clavatum has forking, non-branch- and L. obscurum are frequently harvested and ing aerial stems that typically bear one to two used for decorative greens. Although commonly cones when mature. The aerial stems are often found in aspen-birch forests, these two species tightly packed along the aboveground running are also found in moist rich woods and along rhizomes. In Canada, Aboriginal peoples on edges of bogs. The branching aerial stems Vancouver Island, located in British Columbia, resemble small pine trees: hence the common believed the plant should be left alone. It is said name of princess pine or ground pine. Only the that clubmoss should be left because it is individual mature aerial stems should be “something that gets you confused in the harvested, and this should be done after prime woods” or “confused and uncertain about spore release in late fall. The spores of these orientation” (Turner et al. 1983). Perhaps this two species are flammable when mature and belief stemmed from the random pattern of have been used historically for theatrical and branching that is common for this species. pyrotechnical purposes. In addition, the ground pines have belowground rhizomes Lycopodium annotinum or stiff clubmoss is not running between 2 and 6 inches below the soil traditionally gathered or harvested. Although surface (Nauertz and Zasada, personal observa- considered evergreen, this species tends to dry tions); consequently, a new aerial stem may not out quickly and does not remain green and appear above the soil surface until sometime in pliable, as do the other species harvested for the second year of growth. decorative greens. Lycopodium annotinum has forking, non-branching aerial stems that Lycopodium complanatum, also known as produce a single strobilus, or cone, when ground cedar, is most commonly found in pine mature. The stems are typically densely packed forest communities, typically grows in clumps, along aboveground running rhizomes. and can cover large areas. It has tree-like, branching aerial stems with adpressed and Shining clubmoss or Lycopodium lucidulum is tightly packed microphylls or leaves that most common to northern mesic forests domi- strongly resemble cedar boughs. When mature, nated by sugar maple, preferring the embedded the aerial stems host a “candelabra” of cones acid, wet woods or rocky areas. Native Ameri- for spore production. This species of Lycopo- cans traditionally gathered it for use as pad- dium differs from the ground pines L. ding for cradleboards. L. lucidulum does have dendroideum and L. obscurum, in that it has some features that are unique to this group of aboveground running rhizomes growing clubmoss species. It has forking, non-branch- through the litter layer on the forest floor. ing aerial stems that, when mature at around 6 Lycopodium complanatum is also harvested for years of age, produce sporangia that contain decorative greens and has some homeopathic spores in the leaf axils. In addition, gemmae or and Aboriginal medicinal uses. Harvesting for bulblets may be produced in the upper leaf greens is different for this plant in that the axils. They mature usually in late summer or entire aboveground runner, or rhizome, is early fall, and when bumped will catapult off yanked from the surface of the soil; hence, the the aerial stem and, upon landing in proper entire plant or section of a clone is harvested, growing media and conditions, have the poten- rather than just the mature aerial stems as tial for growing into a new, genetically identical done for the ground pines. Optimal lateral plant. This is a means of vegetatively increasing extention or growth for each rhizome has been plant frequency, but not genetic variation. recorded to occur in year 1 (most recent year Lycopodium lucidulum does not technically growing tip) to year 6, with maximum extension form rhizomes; instead the aerial stems tend to reaching 400 to 600 cm. Greatest aerial stem layer, and then branch and fork. Each fall the mass was recorded in years 3 to 6, with peak leaf litter from the overstory canopy falls, weights reaching 13 to 25 grams (Nauertz and anchoring the layered aerial stems to the Zasada, unpublished data). surface of the forest floor. Adventitious roots for water and nutrient uptake will form along the Running clubmoss, Wolf’s paw, or Lycopodium layered aerial stems. clavatum also has aboveground running rhizomes and is harvested for decorative greens in 111 NTFP Conference Proceedings

LYCOPODIUM REPRODUCTIVE be very dense and vast, or it may be thin and CHARACTERISTICS sparse. Patches of Lycopodium may be located near each other and occur frequently within an Reproduction method, both sexual and area, or there may be large areas where no asexual, may help explain the frequency and Lycopodium occurs at all. cover patterns of individual Lycopodium species. All ferns and fern-allies produce spores Lycopodium, especially ground pine, is often and experience an alternation in generations, found in northern hardwood forests in which is a means of dividing, segregating, and Michigan’s Upper Peninsula. Nauertz (1999) re-combining chromosomes. This allows for conducted a study in these forests to gain genetic variability to occur and for evolution to insight on the species biology and presence in proceed (Lellinger 1985). Spores vary in where managed and unmanaged forests. In addition, they germinate within the soil surface layers as part of a larger study (USDA, FS, NCRS, NC- and were found to germinate at deeper depths 4153-94-03), basal area was measured and as well as on the soil surface (Cobb 1963, recorded in all of these stands in 1995-1996. Freeberg 1962). The spores produced by fern- Four forest types were studied: (1) Unmanaged allies such as Lycopodium may remain viable old-growth forest with trees as old as 250+ for many years and could take up to 7 or more years that have not been disturbed by logging. years to develop into a gametophyte (Cobb Basal area was 23 - 47 m2/ha. (2) Unmanaged 1963). Gametophytes may remain alive from second-growth forest that was clearcut in the only a few weeks or months (Lellinger 1985) to 1910s and now remains unmanaged with trees as long as 10 or more years (Cobb 1963). A that are primarily of second-growth origin. gametophyte bears the sexual mechanisms for Basal area was 26 - 37 m2/ha. (3) Managed reproduction and, given optimal conditions, uneven-aged forest that is of old-growth origin may result in a new, genetically unique sporo- and is managed to have an all-age size distri- phyte or plant that would be recognized as bution using selection cuts and group cuts. Lycopodium. A complete life cycle from spore to Basal area was 20 - 27 m2/ha. (4) Managed gametophyte to sporophyte may take up to 20 even-aged forest that is also of second-growth years. origin and was clearcut around the turn of the century. Crop tree release and thinning have Spore development may potentially lead to a been performed at routine intervals to convert new patch and an increase in frequency. the even-aged stands to an uneven-aged distri- Rhizome growth and expansion will increase bution. Basal area was 21 - 30 m2/ha. the overall area covered by an individual patch. For Lycopodium, as well as for other rhizoma- Nauertz (1999) found that Lycopodium species tous species, a major portion of the expansion occurred in 10 - 67 percent of the 130 plots of cover is created by the growth and branching sampled in the study. Two-thirds of the Lycopo- of the lateral branches or rhizomes. Rhizomes dium present was found in the managed even- are a plant’s mechanism for getting around, aged and unmanaged old-growth stands used exploring new territory, and foraging for new for this study. Highest Lycopodium frequency of resources. At some point, if new resources are occurrence and percent cover values existed in not discovered and exploited, that section of the unmanaged old-growth, managed even- the plant will be cut off physiologically and aged, and unmanaged second-growth stands, another section of the plant will begin to grow respectively. Lycopodium percent cover under and explore for new resources. In general, both these three management regimes was not methods of reproduction, sexual and asexual, statistically different. Lycopodium help to explain Lycopodium distribution. dendroideum, L. lucidulum, and L. annotinum occurred most often across management regimes, with high and statistically similar LYCOPODIUM DISTRIBUTION cover values existing in the unmanaged old- growth, managed even-age, and unmanaged The distribution of Lycopodium in northern second-growth stands. Lycopodium forests tends to vary. These clumps or colonies dendroideum cover (r2 = 0.75; P < 0.01), L. are so well distributed throughout the forest annotinum cover (r2 = 0.66; P < 0.01), and L. that they have a certain amount of randomness lucidulum cover (r2 = 0.49; P < 0.01) were in their distribution (Curtis 1959). A patch may correlated to total Lycopodium cover. Highest

112 Lycopodium frequency and percent cover Another factor to consider is the evergreen occurred under the management regimes with nature of Lycopodium species. Regardless of the highest measured basal area. the forest overstory management regime used, this evergreen characteristic should allow the clubmosses to take advantage of the spring and FOREST MANAGEMENT AND LYCOPODIUM fall light windows that are known to exist in general and that have been recorded in these The basic growth form or morphology of indi- forest stands (Nauertz et al., unpublished vidual clonal species may offer different advan- data). Temperatures near the forest floor tages under different environments. According respond to the increased light during these to Doust (1981), most clonal species are cat- times and become warm enough to support egorized as having either a “guerilla” or a biological processes relatively early and late in “phalanx” strategy. Species that have widely the growing season (Nauertz et al., unpublished spaced individual aerial stems or ramets data). These “windows of opportunity” may be (guerilla strategy) explore a wide area, are important times for photosynthate production successful in discovering and occupying gaps, and storage for the Lycopodium clone. are usually better competitors at low densities, and are more common in early successional At various times during their life cycle, certain habitats (Doust 1981). This strategy may be Lycopodium species may or may not turn out to applied to the tree-like branching Lycopodium be able to adapt to excessive changes in their species such as L. dendroideum, L. obscurum, environment. Much of their adaptive success and L. complanatum. Species with densely will need to be attributed to the “individuality” packed individual aerial stems or ramets of each species. In areas with dense Lycopo- (phalanx strategy) expand slowly; form large dium populations, using forest management clumps; are most successful in close, competi- practices that consider the group as a whole tive environments; and predominate in late will certainly add to their sustainability and successional stages where competition is most overall success. severe (Doust 1981). This strategy, in turn, may be applied to the non-branching aerial stem species of Lycopodium, such as L. DISTURBANCE AND COMPACTION OF THE annotinum, L. clavatum, and L. lucidulum. FOREST FLOOR

In Nauertz’ (1999) study, Lycopodium Soil surface disturbance is a side effect of dendroideum (ground pine) percent cover was logging operations in forest overstory manage- highest and statistically similar in managed ment. On one hand, exposed mineral soil is a even-aged, unmanaged old-growth, and result of these operations and may provide unmanaged second-growth forests. Mean good conditions for spore germination and percent cover of all Lycopodium species com- gametophyte development and, if successful, a bined was greater in unmanaged forest than in pathway for genetic variation. On the other managed forest; however, significant differ- hand, intensive soil disturbance reaching well ences were noted, with the highest mean below the soil surface and excessive soil com- percent cover of L. dendroideum occurring in paction may both result when frequent entries unmanaged forest. Mean percent cover of all are made into managed areas or when logging Lycopodium species combined was significantly is done when soils are wet and more likely to greater in second-growth forest than in old- compact. Consequently, intensive and exces- growth forest; the highest L. dendroideum mean sive conditions may not offer the best habitat percent cover occurred in the second-growth for survival of newly formed gametophytes or forests. In addition, the highest Lycopodium production of a new sporophyte. Considering frequency and percent cover occurred under the length of the life cyle for Lycopodium in the management regimes with the highest general, fewer management entries and less measured basal area. Considering these points, excessive and intensive soil disturbance and it is apparent from this study that a combina- compaction would be beneficial. Compact soils tion of disturbance and time following distur- also make it difficult for species with bance may be required to allow for adequate belowground running rhizomes to expand levels of Lycopodium frequency and cover to vegetatively. Soil compaction will also alter the develop. hydrology, often causing wetland-like conditions. Without optimal resources for success, 113 NTFP Conference Proceedings the Lycopodium clone may not be able to two between harvests within a ground pine sustain itself or reproduce either sexually or patch will also ensure enough time for an vegetatively. increase in vegetative expansion and future harvest potential. In forests of old-growth origin, the pit and mound topography is better defined and more Lycopodium complanatum (ground cedar) and L. variable than in the managed forests of second- clavatum (running clubmoss) are two species growth origin. This variable topography offers a with aboveground rhizomes that are often used variety of microhabitats and resources of which when making wreaths. Harvest on public land Lycopodium, as well as other rhizomatous is not allowed, but these two species are often plants, may take advantage. In general, species gatherered on private land with the permission with aboveground rhizomes such as Lycopo- of the landowner. They are commonly harvested dium annotinum, L. clavatum, and L. by grabbing an end of a rhizome and yanking complanatum, as well as the layering species it, pulling the aerial stems, rhizome, and roots such as L. lucidulum, would have the advantage all out of the forest floor litter layer. However, in wet, rocky areas with compact soil, whereas gathering an entire ground cedar or running species with belowground rhizomes like the clubmoss patch would prevent any surviving ground pines, L. dendroideum and L. obscurum, rhizomes from expanding vegetatively, and would have the advantage in areas where pit would consequently eliminate future harvest and mound topography exists, where the soil is opportunities. Selective gathering from a dense well aerated and of low bulk density. patch is recommended, leaving plants or parts of the patch to branch and expand. In addition, some disturbance from the yanking of rhizomes LYCOPODIUM HARVESTING GUIDELINES during harvest exposes mineral soil and hence AND RECOMMENDATIONS creates good conditions for spore germination.

In the northern forests of Wisconsin, Michigan, Time of harvest of Lycopodium should also be and Minnesota, the ground pines are the most considered for two reasons. First, Lycopodium heavily harvested group of Lycopodium species. species are evergreen perennials that process Typically you will need a permit if you plan to and store photosynthate primarily in the spring harvest ground pine on public land and only before leaf-out of the forest canopy. Since the the mature aerial stems of the ground pine are greatest quantities of Lycopodium are used for considered to be valuable economically for traditional seasonal holiday decorations, it decorative purposes (Wenger 1995). The most would not make sense to gather large quanti- efficient and least destructive way to harvest ties of them in the spring. Second, the Lycopo- ground pine is by clipping the mature aerial dium do not produce spores until the fall, stem or tree-like portion of the plant near the usually sometime between October and mid- base of the stem at ground level. It is less November (Nauertz, personal observations), stressful for the plant if you cut it with a sharp and it is important to consider whether the instrument instead of ripping or tearing it spores are mature and ready to be released or away. Cutting lessens the impact the aerial dispersed before the harvest. This timeline may stem harvest will have on the belowground vary slightly from year to year and can easily be rhizome, allowing it to remain stable in position tested by flicking the cone or strobili with a within the soil below. Matula (1995) reported finger to see if the yellow dust-like spores that disturbances such as harvesting of indi- escape. vidual, mature aerial stems in such a way as not to disturb the underground rhizome may In general, Lycopodium species are considered enhance the survival of the plant by increasing to be a rather slow growing group. A word of belowground rhizome branching. Taking only caution—it is not known how overharvesting the mature or oldest aerial stems and leaving will affect the growth rate of an individual the younger immature stems will ensure future plant, patch, or clone over time. Allowing a harvest opportunities. In addition, skipping a patch to recover for a few years after a harvest year or two between harvests will allow time would ensure future harvest opportunities. Any without disturbance for possible spore germi- abrupt and intensive alteration of growing nation and new plant development. A year or conditions could make it difficult for any type

114 of existing ground vegetation to survive. When Matula, C. 1995. Growth rate, growth patterns, considering whether to gather any forest prod- and effects of harvest of the Lycopodium ucts, whether for timber or non-timber use, it obscurum complex in the Lake Superior is important to consider taking them in moder- region. Eau Claire, WI: University of Wis- ate quantities. The First Nation native tribal consin. M.S. thesis. elders speak wise words: “Take what you need. Pay your respects. Leave the rest.” Meeker, J.E.; Elias, J.E.; Heim, J.A. 1993. Plants used by the Great Lakes Ojibwa. Odanah, WI: Great Lakes Indian Fish and LITERATURE CITED Wildlife Commission. 440 p.

Cobb, B. 1963. A field guide to ferns and their Nauertz, E.A. 1999. Impact of various silvicul- related families. New York, NY: Houghton tural practices on the abundance and Mifflin Company. frequency of Lycopodium species in northern hardwood forests. Houghton, MI: Cody, W.J.; Britton, D.M. 1989. Ferns and Michigan Technological University. 164 p. fern-allies of Canada. Agriculture Canada. M.S. thesis. 430 p. Primack, R.B. 1973. Growth patterns of five Crow, T.R.; Zasada, J.C., principal investiga- species of Lycopodium. American Fern tors. 1994. Impacts of silvicultural treat- Journal. 63(1): 3-7. ments on ecological diversity in northern hardwood ecosystems. Study Plan NC- Shakhashiri, B.Z. 1983. Chemical demonstra- 4153-94-03. St. Paul, MN: U.S. Department tions: a handbook for teachers of chemistry, of Agriculture, Forest Service, North Central vol. 1. Madison, WI: University of Wisconsin Research Station. Press: 103-105.

Curtis, J.T. 1959. The vegetation of Wisconsin: Turner, N.J.; Thomas, J.; Carlson, B.F.; Ogilvie, an ordination of plant communities. Madi- R.T. 1983. Ethnobotany of the Nitinaht son, WI: University of Wisconsin Press. Indians of Vancouver Island. British Colum- bia Provincial Museum. Occas. Pap. Ser. Doust, D.L. 1981. Population dynamics and 24. Province of British Columbia, Ministry local specialization in a clonal perennial of Provincial Secretary and Government (Ranunculus repens). 1. The dynamics of Services. Government of Canada. ramets in contrasting habitats. Journal of Ecology. 69: 743-755. Ullman, D., M.P.H. 1992. A homeopathic perspective on digestion. Homeopathic Flora of North America, Volume 2. 1993. Ferns Educational Services, 2124B Kittredge St., and gymnosperms. New York, NY: Oxford Berkeley, CA 94704. University Press. 475 p. (www.homeopathic.com)

Freeberg, J.A. 1962. Lycopodium Prothalli and Ullman, D., M.P.H. 1997. Homeopathic medi- their endophytic fungi as studied in vitro. cines for indigestion, gas, and heartburn: American Journal of Botany. 49: 530-535. natural remedies you can stomach. Copy- right 1997. Homeopathic Educational Johnson, D.; Kershaw, L.; MacKinnon, A.; Services, 2124B Kittredge St., Berkeley, CA Pojar, J. 1995. Plants of the western boreal 94704. (www.homeopathic.com) forest and aspen parkland. Edmonton, AB: Lone Pine Publishing. 392 p. Wenger, Ed, Compiler. 1995. Lycopodium Issues Workshop. Interagency – Industry Lellinger, D.B. 1985. A field manual of the ferns meeting; 1995 July 27-28; Florence, WI. and fern-allies of the United States and Escanaba, MI: Hiawatha National Forest. Canada. Washington, DC: Smithsonian Institution Press. 389 p.

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