Numerous studies have documented changes in the seasonal timing of organisms’ growth and reproduction in response to climate warming. These changes correlate with documented changes in species’ abundance, but mechanisms linking these trends remain elusive. We investigated the joint demographic effects of advanced reproductive phenology and warming on a globally invasive plant (Carduus nutans) in a field experiment, documenting a substantial shift toward completion of the life cycle at younger ages. Demographic modeling projected 71% of warmed individuals flower as annuals, compared to 61% under current conditions. As this species only reproduces once, this represents a major acceleration of the life cycle. We project a 15% increase in this invader’s population growth rate. We show that rising temperatures accelerate this invasive species’ population growth by increasing the average size of reproducing individuals; increasing the proportion of individuals that survive to reproduce; and increasing the fraction that reproduce as annuals. Major increases in population growth in this, and potentially many other, invasive species will threaten food security and require careful planning to avoid significant environmental and economic impacts.

A full description of the field experiment that produced these data is included in the associated article.

Columns within the file are as follows:

PlotID: A unique identifier for the 10x15 cm area in which the observed plant was grown. This identifier is made up of the Cohort, Block, Plot, Position, and PlantDate, separated by “_”. Details describing each of these values are included below.

z: Plant size in year t, measured as the natural log of the longest leaf length in centimeters. Rosettes were measured at the end of the growing season in early November.

z1: Plant size in year t + 1, measured as the natural log of the longest leaf length in centimeters. Rosettes were measured at the end of the growing season in early November.

Surv: Survival from year t to year t + 1. A value of 0 indicates that the individual died, while a value of 1 indicates that the individual survived.

Repr: Reproduction in year t + 1. A value of 0 indicates that the individual did not reproduce in year t + 1, while a value of 1 indicates that the individual did reproduce in year t + 1.

age: The age of the individual at time t. Individuals measured at the end of their first growing season have age 0, and age increases by 1 each year afterward.

Cohort: The year in which the individual was planted (either 2012 or 2013).

Block: The block in which the individual was planted. Values are not unique between years; each cohort’s block numbering starts at 1.

Plot: The 2x2 m plot in which the individual was planted.

Position: The 10x15 cm area in which the individual was planted.

PlantDate: The seed release timing treatment to which the position was assigned. For plants in the 2012 cohort, the treatments were planted on the following dates:

                1: 8/2/2012

                2: 8/8/2012

                3: 8/21/2012

                4: 9/5/2012

                5: 9/19/2012

                6: 10/3/2012

                7: 10/19/2012

For plants in the 2013 cohort, the treatments were planted on the following dates:

                1: 8/3/2013

                2: 8/12/2013

                3: 8/26/2013

                4: 9/9/2013

                5: 9/24/2013

                6: 10/8/2013

                7: 10/22/2013

OTC: The temperature treatment to which the plot was assigned. A value of 0 indicates the plot was at ambient temperature, while a value of 1 indicates the plot was passively warmed using a fiber glass open top chamber (OTC).

Pred.seeds: The predicted number of seed produced by the individual in year t, estimated based on the diameter of mature capitula harvested in late July.

strata.seedl.otc: The category to which the individual belongs, among the following:

                AmbPlant: an established individual grown at ambient temperature

                AmbSeedl: a newly established rosette grown at ambient temperature

                OTCPlant: an established individual grown under passively warmed conditions in an OTC

                OTCSeedl: a newly established rosette grown under passively warmed conditions in an OTC