The impacts of aerial leaf (trophophore and sporophore) removal on reappearance and trophophore size the following year was studied in two species of moonworts (Botrychium subgenus Botrychium). Aerial leaves of B. matricariifolium and B. lanceolatum angustisegmentum were removed either before spore release in the spring or after spore release in the late summer. Leaf removal did not have an impact on the percent re-emergence of leaves the following year, regardless of the time of removal. Aerial leaf removal before spore release also had no impact on the size of leaves (i.e. length and width of trophophore and the length of the basal pinna) produced the following year. However, in plants having their leaves removed after spore release, the size of the next year's leaves were significantly smaller than control plants of the same year. This suggests that some of the energy expended in the maturation of spores may need to be recovered from the above-ground structures in order to produce the same size aerial leaf the next year. Removing the above-ground leaf before sporulation allows the plant to retain sufficent energy reserves to produce the same size leaf the following year.

Key words: Botrychium lanceolatum var. angustisegmentum, Botrychium matricariifolium, leaf removal, Ophioglossaceae