This report is another in a series of plant studies under investigation at the UWM Cedar-Sauk Field Station. Most of the previous studies were concerned with seed plants and only limited attention was given to the fern flora. In this study, carried out chiefly in the summer of 1970, the fern species were evaluated to determine their importance, distribution and ecological relationships in the maple-beech forest

Carlsen, Theodore E

English

University of Wisconsin-Milwaukee

University of Wisconsin MilwaukeeUWM Digital CommonsField Station Bulletins UWM Field StationFall 1971Distribution of ferns in the Maple-Beech Forest atthe Cedar-Sauk Field StationTheodore E. CarlsenBrookfield High SchoolFollow this and additional works at: https://dc.uwm.edu/fieldstation_bulletinsPart of the Forest Biology Commons, and the Zoology CommonsThis Article is brought to you for free and open access by UWM Digital Commons. It has been accepted for inclusion in Field Station Bulletins by anauthorized administrator of UWM Digital Commons. For more information, please contact open-access@uwm.edu.Recommended CitationCarlsen, T.E. 1971. Distribution of ferns in the Maple-Beech Forest at the Cedar-Sauk Field Station. Field Station Bulletin 4(2): 1-6.THE UNIVERSITY OF WISCONSIN-MILWAUKEEFIELDSTATIONS / -~t- .='BULLETIN ~_~~ ~---~Vol. 4, No.2 Milwaukee, Wisconsin Fall,1971DISTRIBUTION OF FERNS IN THE MAPLE-BEECH FOREST ATTHE CEDAR-SAUK FIELD STATIONThis report is another in a series of plant studies under investigation at theUWM Cedar-Sauk Field Station. Most of the previous studies were concerned withseed plants and only limited attention was given to the fern flora. In this study,carried out chiefly in the summer of 1970, the fern species were evaluated todetermine their importance, distribution and ecological relationships in themaple-beech forest.METHOD OF STUD YBecause ferns are less common and more widely dispersed than other under-story plants, they cannot be adequately sampled in random quadrats. The lineintercept method of sampling (Oosting, 1956) seemed to be the best techniqueto use. In this method, fourteen parallel transect lines, oriented W-E and parallelto the north boundary of the woods, were laid out by means of a staff compassand marked with bailing twine. The lines were approximately 100 feet apart andwere initiated at the western boundary fence and extended to the eastern end ofthe wooded tract. The fern species were recorded whenever they interceptedthese lines or occurred within 0.5m on either side of the lines. Each cluster offronds from a common center was considered as one individual, and only onefrond had to be in the intercept area to be counted. The species were tabulatedas to their frequency, relative abundance and general distribution within thesampled area.Environmental factors which were observed or analyzed included lightintensity, pH and soil moisture. Each was determined from readings or samplestaken wherever a "patch" of ferns was located. Light readings were taken be-2tween the hours 0110:00 a.m. and 2:00 p.m. on sunny days. The hydrogen iont;oncentration was determined by sifting a sample of soil, preparing a 4% suspen-sion in distilled water and reading the pH value to the nearest 0.1 using a Beck-man pH Meter. Soil moisture was recorded as a percentage of the moisture in theoriginal soil sample after drying and reweighing. Voucher specimens were alsocollected and are filed in the Field Station herbarium.DiSCUSSIONSeven fern species were present in sufficient numbers to be recorded andevaluated: Rattlesnake Fern (Botrychium virginianum (L.) Sw.), Lady Fern(A thyrium felix-femina (L.) Roth), Cinnamon Fern (Osmunda cinnamomea L.),Spinulose Shield Fern (Dryopteris spinulosa (O.F. Muell.) Watt), Maidenhair Fern(Adiantum pedatum L.), Fragile Fern (Cystopteris fragilis (L.) Bernh.) andBracken Fern (Pteridium aquilinum (L.) Kuhn). To indicate how widespreadeach species is in this woods, their frequencies were computed. The frequency ofeach species was determined as a percentage of the total number of lines in whichit was tallied (Table 1.). The Rattlesnake Fern is the most widespread species,occuring in all of the transect lines (100%). The Lady Fern ranked second, occur-ring in 64.3% of the lines, and was followed by the less widespread species ofMaidenhair Fern (28.6%), Cinnamon Fern (28.6%), Spinulose Shield Fern (21.4%),Fragile Fern (14.3%) and the Bracken Fern (7.1%). These frequency values forthe Rattlesnake Fern and the Lady Fern are in general agreement with similarstudies by Curtis (1959) and his students who found the average frequencies ofthe Rattlesnake Fern and the Lady Fern were 65% and 49%, respectively, inother southern mesic forests of Wisconsin.These species have a similar relationship as to their abundance, which isalso shown in Table 1. Abundance of each species was calculated as a percentageof the total number of all plants recorded, and represents the density of individ-uals of a particular species in the sample area. Again, Rattlesnake Fern ranks firstas 60.8% of the plants tallied were of this species. Lady Fern ranked second withan abundance of 12.7%, while the others were sparsely present as indicated byabundance percentages ranging from 2.4% to 9.6%.Although the above data indicate quantitatively the variation in numbersand spatial distribution of these fern species, it is necessary to consider some ofthe environmental factors for possible reasons for these patterns. Some of thesepossible relationships may be obtained from the environmental data collectedand shown in Tables 2, 3, and 4.The extensive distribution of the Rattlesnake Fern is probably due to itsadaptability to the environmental conditions associated with a mature uplandhardwood forest. It thrives in the low light intensity produced by the almostcomplete canopy, on various sites with variation in soil moisture (4.1% to 10%)and it tolerates a pH range from 5.2 to 7.5. Its distribution in the stand, however,3Table 1. Frequency and Abundance of Each Fern Species.SpeciesRattlesnake FernLady FernMaidenhair FernBracken FernFragile FernCinnamon FernShield Fernf'reque",cy (%)100.064.328.67.114.328.621.4Abrmda",ce (%)60.812.76.49.65.62.62.4Table 2. Number of Individuals of Each Species in Relation to Light Intensity.E E Ev vU. U. v Ev u. c-'".~ E " ~'"E'"c v U. v~ v ..c 0 u. c u.Light u. c E v v~" '" ""-'"'SoIntensity'" ""c ~ u""... c'" ~(foot-candles) '" '" ~ U ..c ~0:: -l Vl u.0-50 5 151-100 12 5 2101-150 5151-200 3 2201·250251-300 3 2301-350 1351-400 4401-450451-500 2501-550551-600 2951-10001001-15001501-20002001-25002501·30003001·35003501-40004001-45004501-50005001-55005501-60008001-85004Table 3. Number of Individuals of Various Species Observed in Relation toSoil Moisture Percentages.c E~<Uu.. <U Eu.. EE .~ E<U"C<U u.. <U<U ..c 0 u.. c u..u.. c E <U <U<U .. -0-'" :-::l>- :2 c ., u""-0 .. 5 :.c .. ....eO u:....l ~ U (/)SoilMoisture (%)4.1 ·4.54.6·5.05.1·5.55.6 - 6.06.1 - 6.56.6 - 7.07.1-- 7.57.6 - 8.08.1 - 8.58.6·9.09.1 - 9.59.6 - 10.010.1 - 10.510.6 - 11.011.1-11.511.6 - 12.014.6 - 15.015.1 - 15.519.6 - 20.025.6· 26.0E<Uu..<U-'""~~~cr:1123I454314I221111is not uniform. It is sparse on exposed slopes which are too dry and in the openaspen grove at the east end of the area where the soil moisture is extremely lowand the light intensity is very high.The Lady Fern shows a similar, but somewhat greater, range of variabilityfor these factors. It occurs where the soil moisture ranges from 4.1 % to 26.0%,the pH ranges from 4.3 to 7.2 and in light conditions similar to those favorableto the Rattlesnake Fern. Except for the Bracken Fern, the other species havesimilar light preferences but appear to have different soil moisture or pH prefer-ences. The Shield Fern and the Cinnamon Fern have higher soil moisture require-ments (11.6% to 20.0%) and were noted chiefly in low moist areas of the woods,while the Maidenhair Fern and the Fragile Fern have a greater affinity for morealkaline soils as evidenced by their presence in sites where the pH ranged from6.8 to 7.5.The Bracken Fern was the least frequently observed species, as it wasrecorded only in an aspen grove at the extreme eastern edge of the study area.Curtis (1959) considers both the aspen tree and the Bracken Fern as specieswhich quickly invade burned over areas. This fern thrives under higher light5intensities than the others, and spreads readily by means of a rapidly growingrhizome. It appears to have a long life-span and may persist, but not spreadsignificantly, as the shade increases when trees invade the area.These environmental factors not only affect the distribution of the maturefern plants (sporophytes) but, undoubtedly, influence the entire life-cycle ofthese plants. Spores, the propagules produced by ferns, are viable for only a shorttime and depend upon the wind for dispersal. In a dense forest wind velocity isgreatly reduced and spores produced on the undersides of fronds, as in the LadyFern, Maidenhair Fern, Fragile Fern and Bracken Fern, have a poorer chance foreffective dispersal than those borne on upright spikes, as in the Rattlesnake Fernand the Cinnamon Fern, because an animal or a slight breeze may cause sufficientmotion to project the spores some distance from the parent plant. If the sporesTable 4. Number of Individuals of Each Species Observed in Relation toHydrogen Ion Concentrations (pH).E c E".."l.L. l.L."C"l.L. E.. E.:.< E .!:l "os os C"l.L."!:i " ..c 0 l.L. c: l.L.l.L. C E" "..!! >- " os :g .:.< '&,::? c"uos '" os .S ~ os osos a:i t.tpH ~ -l ~ U til4.34.55.25.35.45.55.65.7 15.8 25.9 16.0 16.1 2 26.26.3 16.4 26.5 16.6 16.7 16.8 56.9 27.0 17.2 37.3 27.47.56land in a habitat with favorable moisture and absence of competition, theygerminate rapidly and produce chlorophyllous gametophytes. The RattlesnakeFern has another feature which is not present in the other ferns of this stand. Itproduces a subterranean achlorophyllous gametophyte, which may enable it todisperse more readily because it can tolerate lower moisture requirements andlower light conditions for survival.Although the relationships with other understory plants were not investi-gated, some observations were made which may be significant for the numbersand distribution of ferns in this woods. In those portions of the stand where thecanopy was densest, and where cool moist microclimatic and reduced light con-ditions existed, the ferns appeared to thrive best with little competition fromherbaceous seed plants. In disturbed areas grasses and shrubs were generallypresent and ferns were notably absent, probably because of the higher lightintensities and drier soils. Ferns were also absent where the understory consistedof dense sapling growth or the canopy was so dense that the forest floor wascovered only with leaf litter.Ferns, although not as abundant or as extensively distributed as herbaceousseed plants, are quite sensitive to light, soil moisture and pH variations, and areof some significance in demonstrating the variation of these environmental factorswithin a plant community such as this maple-beech woods.I am grateful for the technical and advisory help provided by Dr. Peter J.Salamun and Mr. Paul Matthiae. Also, special thanks are extended to Dr. Salamunfor his critical reading and editing of this manuscript.LITERA TURE CITEDBillingon, C. 1952. Ferns ofMichigan. Cranbrook Institute of Science, BulletinNo. 32. Bloomfield Hills, Mich.Curtis,]. T. 1959. The Vegetation of Wisconsin, An Ordination of Plant Com-munities. The University of Wisconsin Press, Madison.Fernald, M. L. 1950. Gray's Manual of Botany. American Book Co. 8th ed.Foster, A. S. and E. M. Gifford. 1959. Comparative Morphology of VascularPlants. W. H. Freeman Co., San Francisco.Morzenti, D. B. ] 969. The Water Retaining Capacity and Temperature Develop-ment from Soils from Various Habitat Types at the UWM FieldStation. Unpublished Report.Oosting, H. J. 1956. The Study of Plant Communities. W. H. Freeman Co., SanFrancisco.Tryon, R. M. et a11953. The Ferns and Fern Allies of Wisconsin. The Universityof Wisconsin Press, Madison.Theodore E. arisenBiology TeacherBrookfield High School

Distribution of ferns in the Maple-Beech Forest at the Cedar-Sauk Field Station

https://dc.uwm.edu/cgi/viewcontent.cgi?article=1027&amp;context=fieldstation_bulletins

Distribution of ferns in the Maple-Beech Forest at the Cedar-Sauk Field Station

Abstract

Similar works

Full text

Available Versions

University of Wisconsin-Milwaukee