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the weight of the leaves collected, the following formula was used to calculate the
total leaf biomass per individual:
(dried leaf weight/number of leaves collected) × (total number of leaves on the
plant)
This leaf biomass was used to account for plant size in statistical analysis.
Multiple regression was used to examine the relationship between percent leaf
removal and flower number with plant size as the covariate. Multiple regression
was also used to examine the relationship between percent leaf removal and seed
mass with flower number as the covariate. Type III GLMs were run to examine
the effect of the different treaments (leaf removal, meristem removal, and con-
trols) on both flower number and seed mass. Plant size was run as a covariate for
flower number, and flower number was used as a covariate for seed mass. We also
corrected for the actual biomass of the leaves removed since the meristem removal
often removed leaves. The level of Type III GLM analysis was also used to test for
effects of different levels of leaf removal on flower number and seed mass. Bonfer-
roni tests were performed for multiple comparisons. For all these analyses, seed
mass and flower number were square root transformed.
Acknowledgements
Thanks to Bryan Foster, John Haarstad, Troy Mielke, Cini Brown, Lenny Sheps
and Joe Craine for their help and support in the field. We extend our thanks
to Ian Dickie and Janneke HilleRisLambers for advice and comments on earlier
versions of this manuscript. This work was supported by the NSF as part of the
Research Experience for Undergraduates supplement grant.
References
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Nature 1985, 314:163-164.
2. Huntly N: Herbivores and the dynamics of communities and ecosystems.
Annual Review of Ecology and Systematics 1991, 22:477-503.
3. Mauricio R, Bowers MD, Bazzaz FA: Pattern of leaf damage affect fitness of the
annual plant Raphanus sativus (Brassicaceae). Ecology 1993, 74:2066-2071.
4. Ehrlen J: Demography of the perennial herb Lathyrus vernus. I. Herbivory and
individual performance. Journal of Ecology 1995, 83:287-295.
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