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The decision to establish a network of researchers centers on identifying shared research goals. Ecologically specific regions, such as the USA’s National Ecological Observatory Network’s (NEON’s) eco-climatic domains, are ideal locations by which to assemble researchers with a diverse range of expertise but focused on the same set of ecological challenges. The recently established Great Lakes User Group (GLUG) is NEON’s first domain specific ensemble of researchers, whose goal is to address scientific and technical issues specific to the Great Lakes Domain 5 (D05) by using NEON data to enable advancement of ecosystem science. Here, we report on GLUG’s kick off workshop, which comprised lightning talks, keynote presentations, breakout brainstorming sessions and field site visits. Together, these activities created an environment to foster and strengthen GLUG and NEON user engagement. The tangible outcomes of the workshop exceeded initial expectations and include plans for (i) two journal articles (in addition to this one), (ii) two potential funding proposals, (iii) an assignable assets request and (iv) development of classroom activities using NEON datasets. The success of this 2.5-day event was due to a combination of factors, including establishment of clear objectives, adopting engaging activities and providing opportunities for active participation and inclusive collaboration with diverse participants. Given the success of this approach we encourage others, wanting to organize similar groups of researchers, to adopt the workshop framework presented here which will strengthen existing collaborations and foster new ones, together with raising greater awareness and promotion of use of NEON datasets. Establishing domain specific user groups will help bridge the scale gap between site level data collection and addressing regional and larger ecological challenges.

 

Populations of many tree species exhibit synchronous and highly temporally variable seed crops across years. This is called mast seeding, and there are two predominant hypotheses for this pattern of reproduction: pollination efficiency and seed-predator satiation. Mast seeding studies typically involve records of population-level reproduction, with less information on the characteristics of reproductive structures. Here, we use data across 6 years (2012–2017), spanning a range of population-level cone conditions, to characterize (i) white spruce (Picea glauca (Moench) Voss) cone lengths and seeds per cone, and (ii) levels of seed predation. We quantified population-level cone production and collected 1399 cones from a total of 38 trees in the Huron Mountains, Michigan, USA. Linear mixed models showed that mean and minimum cone lengths varied significantly across years; both being longest during the greatest cone production year. Larger cones had more seeds and the slopes of the relationships as well as the intercepts varied significantly across years. Generalized linear mixed models and Akaike’s information criterion model selection showed that cones with insect predation damage was greatest when population-level reproduction was the lowest, with a mean proportion of cones damaged 0.82 in that year. Our findings show that white spruce cone characteristics and losses to insect seed predation vary temporally, and follow expectations based on mast seeding hypotheses. 

Our overall objective is to synthesize mast-seeding data on North American Pinaceae to detect characteristic features of reproduction (i.e. development cycle length, serotiny, dispersal agents), and test for patterns in temporal variation based on weather variables. We use a large dataset ( n = 286 time series; mean length = 18.9 years) on crop sizes in four conifer genera ( Abies , Picea , Pinus , Tsuga ) collected between 1960 and 2014. Temporal variability in mast seeding (CVp) for 2 year genera ( Abies , Picea , Tsuga ) was higher than for Pinus (3 year), and serotinous species had lower CVp than non-serotinous species; there were no relationships of CVp with elevation or latitude. There was no difference in family-wide CVp across four tree regions of North America. Across all genera, July temperature differences between bud initiation and the prior year (Δ T ) was more strongly associated with reproduction than absolute temperature. Both CVp and Δ T remained steady over time, while absolute temperature increased by 0.09°C per decade. Our use of the Δ T model included a modification for Pinus , which initiates cone primordia 2 years before seedfall, as opposed to 1 year. These findings have implications for how mast-seeding patterns may change with future increases in temperature, and the adaptive benefits of mast seeding. This article is part of the theme issue ‘The ecology and evolution of synchronized seed production in plants’.