DOI: 10.5061/dryad.8pk0p2nk4
title: Data from: Lythrum salicaria common garden under Neogalerucella herbivory

description: We transplanted1088 seedlings of the invasive perennial
 plant Lythrum salicaria (purple loosestrife), from 136 maternal
 families sourced from 17 populations in the region around Ottawa,
 Canada, into a common garden containing 4 plots. The 17
 populations differed in their prior exposure to the biocontrol agent
 Neogalerucella spp. leaf beetles (naïve = no prior exposure; recent =
 secondary colonization, ~5-15 years; release = sites of biocontrol
 release, ~20 years ago). Plants were planted in a wetland containing other
 Lythrum plants and experienced ambient (but significant)
 herbivory by Neogalerucella spp. leaf beetles. We
 measured herbivory, plant size and biomass over
 a period of 3.5 years; see the publication for more details. This
 experiment used the same seed material as a previously published
 greenhouse study by Stastny & Sargent 2017 (see below). Additional
 datasets, such as the proportion and phenology of flowering individuals,
 leaf size, stem and meristem numbers, etc., are available upon
 request.  
description: At the time of transplanting (year 1), we measured plant height,
 corresponding to the variation in growth under greenhouse conditions.
 Afterwards, in years 2 and 3, we measured the sum length of all stems
 (mm); this metric corresponds to the early-season plant size prior
 to <em>Neogalerucella </em>herbivory, and gives an indication
 of the variation in regrowth and phenology early in the season. In year 4,
 when we terminated the common garden, we measured this metric directly as
 dry above-ground biomass (g). In the dataset, these three metrics are
 listed under parameters that include "size" in column header. In
 years 1-3, we visually estimated herbivory (as a reflection of the
 variation in resistance) for each plant, as percent defoliation
 (parameters that include “damage” in column header), i.e. the percentage
 of the leaf area removed by <em>Neogalerucella</em> feeding.
 This metric represents the main bout of herbivory in the growing season.
 Finally, at the end of each growing season in years 1-3 we
 measured above-ground biomass (parameters that include “biomass” in column
 header); this metric integrates the outcome of seasonal herbivory as well
 as any variation in tolerance to damage.
description: Each row represents a unique single plant. NAs were recorded when
 a plant was missing during the measurement or, in some cases, when a
 confounding factor (e.g. sporadic deer herbivory) prevented an accurate
 estimate of defoliation by <em>Neogalerucella</em>. In many
 cases, these "missing" plants reappeared at another time point,
 i.e. they were alive but either not actively investing into above-ground
 biomass, or their regrowth showed a more delayed phenology. In the latter
 case, depending on the perspective/question, some of these plants could be
 recorded as 0 (zero) rather than NA - this version of the dataset is
 available upon request, or can be inferred by checking whether the plant
 was recorded (i.e. alive) at later time points. Other
 notes/column designations: pop = population; fam = family within a given
 population; popfam = concatenation of pop and fam; id = unique
 identification code for each plant; history = history of exposure of
 <i>Neogalerucella spp.</i>; plot = plot within common garden,
 also a blocking factor in the complete randomized block design (each
 family is replicated twice within a plot); x, y = row and position within
 row for each plot, corresponding to the spatial coordinates (in
 meters)