Both the location and seasonality of the bud bank affect a plant’s ability to spread vegetatively and recover from disturbance or injury. Characterize a clonal species according to the following categories based on Klimeš and Klimešova (2005) and Klimešova and Klimeš (2006):
A. Vertical distribution of the bud bank. Count the number of buds per clonal fragment (shoot or belowground stem or root) for each height layer, and classify as follows: A) no buds per clonal fragment, B) 1-10 buds per clonal fragment, C) >10 buds per clonal fragment. Assign this classification for each of the height layers: >10 cm below the surface, -10 to 0 cm below the surface, at the soil surface, 0 to 10 cm above the soil surface, and >10cm above the soil surface.
B. Seasonal distribution of the bud bank. For aboveground and belowground clonal fragments, classify the buds as being A) seasonal, B) perennial, C) seasonal and potential, or D) perennial and potential. Perennial buds are found on perennial organs, such as woody stems, perennial shoot bases, or rhizomes (e.g. Trifolium pratense, Agropyron, repens, Petasites hybridus). Seasonal buds are found on transient organs, such as aboveground stems of herbs, stem tubers, bulbs, and bulbils (e.g. Stachys palustris, Ficaria verna, Allium vineale, Dentaria bulbifera). Potential buds are those that are formed adventitiously de novo following disturbance, such as on roots that produce regenerative or regular adventitious suckers (e.g. Potentilla anserina, Convolvulus arvensis). Obviously, unlike the other observations, development of potential buds can only be assessed sometime after a plant is actually injured.
Four other clonal traits may provide useful information on plant response to disturbance or injury, but require observations over time on marked shoots or individuals to classify them. These traits are (1) average lifespan of a shoot (<1 year or >1 year), (2) persistence of the connection between parent and offspring shoots (< 1 year, 1-2 years, and > 2 years), (3) average number of offspring shoots per parent shoot per year (<1 shoot, 1 shoot, 2-10 shoots, and >10 shoots), and (4) mean rate of lateral spread per year (<0.01 m, 0.01-0.25 m, >0.25 m). This last trait does not apply to dispersible reproductive structures such as turions that become disconnected from the parent shoot and can travel long distances.
There are now several plant trait databases in which clonal growth and bud bank types have been categorized for different species using classifications similar to that given here. For north-western and central Europe, these include the LEDA database and the CLO-PLA database.
Supplementary Material 3. References
Klimeš L, Klimešová J (2005) Clonal traits. In: ‘The LEDA Traitbase. Collecting and measuring standards of life-history traits of the Northwest European ﬂora’. (Eds IC Knevel, RM Bekker, D Kunzmann, M Stadler, K Thompson) pp. 66-88. (LEDA Traitbase project, University of Groningen: Groningen, The Netherlands).
Klimešova J, Klimeš L (2006) CLO-PLA3: a database of clonal growth architecture of Central European plants. Available at http://clopla.butbn.cas.cz