Eurasian honeysuckle species such as Lonicera maackii (Rupr.) Herder and Lonicera tatarica L. have a long history as valued and widely planted components of both urban and rural landscapes, prized for their sweetly scented flowers, persistent and colorful fruit, and wide tolerance of climactic conditions since their introduction from Asia to the western hemisphere during the late 1800s to early 1900s (Bailey, 1919; Luken and Thieret, 1996). However, the tendency for Eurasian honeysuckles to escape cultivation and cause ecosystem changes in North America was first documented in the mid 1900s (Luken and Thieret, 1996), and public perception of these taxa has shifted to the point that they are being removed from nursery inventories and even banned in some parts of the United States (U.S. Department of Agriculture Natural Resources Conservation Service, 2018a). Given the long history of consumer demand for Lonicera spp. from Eurasia, the identification and propagation of native alternatives for the North American horticulture trade seems prudent.
Mountain fly honeysuckle [Lonicera villosa (Michx.) Schult.] is an attractive shrub that may have value as a small native alternative to cultivars of blue honeysuckle (Lonicera caerulea L.) that recently have been developed from Eurasian germplasm (Gerbrandt et al., 2017). Because of its similarities to Eurasian members of the species complex, mountain fly honeysuckle is also commonly considered to be a subspecies or variety of a broadly distributed L. caerulea, although it differs in morphology from its Eurasian congeners (Fernald, 1925) and the taxonomy is not settled (Peterson et al., 2018). Mountain fly honeysuckle is indigenous to much of Canada, with a patchy range that extends into the northeastern and Great Lakes regions of the United States, although it is presumed extirpated in Ohio and is endangered in Pennsylvania (U.S. Department of Agriculture Natural Resources Conservation Service, 2018a).
Mountain fly honeysuckle is typically found in bogs and fens, in addition to mesic forests, as a small shrub that occasionally reaches 3 to 4 ft in height. Its coriaceous and rugose leaves are dark green and sparsely to densely pubescent with a pale abaxial surface (Fernald, 1925). Mountain fly honeysuckle displays reddish brown to coppery stems, and bark that exfoliates into persistent strips as the stems age. Plants produce small, paired yellow flowers in early spring, and edible-but-tart oblong blue fruit that ripens in early summer. The fruit is also attractive to birds, but seems to be produced in low abundance within natural habitats.
Propagation of native plants is a necessary first step toward developing them for horticultural or conservation purposes. Stem cuttings often are rooted to produce plants both for sale in the horticulture industry (Hartmann et al., 2011) and for restoration of natural ecosystems (Dreesen et al., 2002). Cutting phenology, method of irrigation (Svenson, 2018), medium composition (Al-Salem and Karam, 2001), and plant growth regulator treatments all influence rooting success, and optimal treatments are often taxon specific (Dirr and Heuser, 2006; Hartmann et al., 2011). Successful introduction of mountain fly honeysuckle to the horticulture trade will depend, moreover, on its capacity to establish and thrive in developed landscapes that may be dissimilar from native environments.
We assessed root development on stem cuttings of mountain fly honeysuckle that were treated with solutions varying in concentration of K-IBA and inserted into propagation media varying in their proportions of coarse perlite and milled peatmoss. The effects of these treatments were evaluated in both overhead mist and subirrigation systems, with the former representing a reliable industry standard and the latter representing a low-cost and low-tech alternative that may produce comparable, or even superior, results for some taxa (Svenson, 2018; Zhang and Graves, 1995). We also planted rooted cuttings of mountain fly honeysuckle into a garden plot and evaluated their survival and growth over 2 years.
Al-Salem, M.M. & Karam, N.S. 2001 Auxin, wounding, and propagation medium affect rooting response of stem cuttings of Arbutus andrachne HortScience 36 976 978
Bailey, L.H. 1919 The standard cyclopedia of horticulture. Vol. 2. Macmillan, New York, NY
Bouma, T.J., Nielsen, K.L. & Koutstaal, B. 2000 Sample preparation and scanning protocol for computerised analysis of root length and diameter Plant Soil 218 185 196
Coggeshall, M.V. & Van Sambeek, J.W. 2001 Development of a subirrigation system with potential for hardwood tree propagation Proc. Intl. Plant Prop. Soc. 51 443 448
de Mendiburu, F. 2016 agricolae: Statistical procedures for agricultural research. R package version 1.2-4. <https://CRAN.R-project.org/package=agricolae>
Dirr, M.A. & Heuser, C.W. Jr 2006 The reference manual of woody plant propagation. Timber Press, Portland, OR
Dreesen, D., Harrington, J., Subirge, T., Stewart, P. & Fenchel, G. 2002 Riparian restoration in the Southwest: Species selection, propagation, planting methods, and case studies, p. 253–272. In: R.K. Dumrose, L.E. Riley, and T.D. Landis (eds.). Natl. Proc.: Forest and Conservation Nursery Assn., 1999, 2000, and 2001. Proc. RMRS-P-24. U.S. Dept. Agr. Forest Serv., Rocky Mountain Res. Sta., Ogden, UT
Gerbrandt, E.M., Bors, R.H., Chibbar, R.N. & Baumann, T.E. 2017 Spring phenological adaptation of improved blue honeysuckle (Lonicera caerulea L.) germplasm to a temperate climate Euphytica 213 172 doi: 10.1007/s10681-017-1958-5
Hartmann, H.T., Kester, D.E., Davies, F.T. & Geneve, R.L. 2011 Hartmann and Kester’s plant propagation: Principles and practices. 8th ed. Prentice Hall, Upper Saddle River, NJ
Lesnoff, M. & Lancelot, R. 2012 aod: Analysis of overdispersed data. R package version 1.3. <http://cran.r-project.org/package=aod>
Peterson, B.J., Stack, L.B. & Hayes, D.J. 2018 What do we know about the invasive potential of Lonicera caerulea L. cultivars in North America? Acta Hort. 1191 129 138
R Core Team 2016 R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. <https://www.R-project.org/>
U.S. Department of Agriculture Natural Resources Conservation Service 2018a The PLANTS database. National Plant Data Team, Greensboro, NC. 14 Feb. 2018. <http://plants.usda.gov>
U.S. Department of Agriculture Natural Resources Conservation Service 2018b Web soil survey. 9 July 2018. <https://websoilsurvey.sc.egov.usda.gov/>
Vittinghoff, E., Glidden, D.V., Shiboski, S.C. & McCulloch, C.E. 2011 Regression methods in biostatistics: Linear, logistic, survival, and repeated measures models. 2nd ed. Springer Science & Business Media, New York
Zhang, H. & Graves, W.R. 1995 Subirrigation to root stem cuttings: Comparison to intermittent mist and influence of fertilization HortTechnology 5 265 268