pollinators limit seed production in an early blooming rare plant: evidence of a mismatch between plant phenology and pollinator emergence

The reproductive ecology of rare plants is seldom studied, yet the persistence of plant populations depends on successful mutualisms with pollinators.  As atmospheric temperatures rise, phenology of plants and pollinators may become mismatched.  We investigated the reproduction of Trifolium barnebyi (Barneby’s Clover), a mat-forming perennial endemic to central Wyoming, USA that grows in the crevices of sandstone bedrock.  Our objectives were to evaluate a method for monitoring changes in cover as well as assess the pollination and seed-set of T. barnebyi.  We established five monitoring transects using a divided frame to estimate percent cover.  We conducted seed-set experiments at three locations to measure self-pollination and the degree to which pollinating insects limited seed production.  We used vane traps and bee bowls to capture pollinators, and examined pollen carried on bees.  Percent cover along transects declined over the 4 year period and was associated with spring precipi..., Monitoring
To assess the cover and asexual reproduction of T. barnebyi, we monitored five transects annually in July between 2018 and 2021. We established two transects at the Weiser Knoll site (Weiser Slope and Weiser Seedlings) and the Hall Creek site (Hall 1 and Hall 2), and one transect at South Red Canyon (Fig. 1). Each transect consisted of a belt between 6.9 and 18 m in length where a plot frame (30 x 30 cm) with sixteen 7.5 x 7.5 cm cells was placed on the ground along the belt to assess cover (Fig. 2).  We used a plot frame to monitor T. barnebyi because the compact and extensive mats of this species make distinguishing individuals difficult without destructive sampling.  We placed the plot frame on one side of the belt at all sites expect South Red Canyon and Weiser Knoll Seedling, where we placed the frame above and below the belt.  We counted the number of cells with T. barnebyi present within each frame at 30 cm intervals.  Cells were scored as present (1) or absent (0) to ..., All analyses were done in Program R (R Core Team 2017)., # Trifolium barnebyi pollination and monitoring

## Description of the data and file structure

2021TrifoliumBarnebyiClimateAndMonitoringData.csv Monthly temperature in degrees Fahrenheit and total precipitation in inches in Lander Wyoming (nearest weather station; https://wrcc.dri.edu/cgi-bin/cliMAIN.pl?wy5390); Spring precipitation totals in inches; Percent occupied cells in monitoring frame by location; All by year 2018-2021
no NA values

2021TrifoliumBarnebyiSeedSet.csv has the seed set treatment, number of flowers, number of viable seeds, day of year harvested, location of plant.

Variables:
* Treatment (Bagged = pollinators excluded from flowerhead throughout blooming, HP = hand pollinated with extra pollen with pollinator access throughout blooming, Open = pollinator access throughout blooming);
* PlantNo (unique plant identifier);
* NoFlower (number of flowers on flowerhead);
* NoOvules (number of ovules in the flowerhead);
* OvulesPerFlw (mean ovules per flower in the flowe...