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Honey bees are renowned architects. The workers use expensive wax secretions to build their nests, which reach a mature, seemingly steady state, relatively quickly. After nest expansion is complete, workers do not tear down combs completely and begin anew, but there is the possibility they may make subtle changes like adding, removing, and repositioning existing wax. Previous work has focused on nest initiation and nest expansion, but here we focus on mature nests that have reached a steady-state. To investigate subtle changes to comb shape over time, we tracked six colonies from nest initiation through maturity (211 days), photographing their combs every 1–2 weeks. By aligning comb images over time, we show that workers continuously remove wax from the comb edges, thereby reducing total nest area over time. All six colonies trimmed comb edges, and 98.3% of combs were reduced (n = 59). Comb reduction began once workers stopped expanding their nests and continued throughout the experiment. The extent to which a comb was reduced did not correlate with its position within the nest, comb perimeter, or comb area. It is possible that workers use this removed wax as a reserve wax source, though this remains untested. These results show that the superorganism nest is not static; workers are constantly interacting with their nest, and altering it, even after nest expansion is complete. 

Abstract Agricultural activity is a significant source of greenhouse gas emissions. The fertilizer production process emits N₂O, CO₂, and CH₄, and fertilized croplands emit N₂O. We present continuous airborne observations of these trace gases in the Lower Mississippi River Basin to quantify emissions from both fertilizer plants and croplands during the early growing season. Observed hourly emission rates from two fertilizer plants are compared with reported inventory values, showing agreement for N₂O and CO₂emissions but large underestimation in reported CH₄emissions by up to a factor of 100. These CH₄emissions are consistent with loss rates of 0.6–1.2%. We quantify regional emission fluxes (100 km) of N₂O using the airborne mass balance technique, a first application for N₂O, and explore linkages to controlling processes. Finally, we demonstrate the ability to use airborne measurements to distinguish N₂O emission differences between neighboring fields, determining we can distinguish different emission behaviors of regions on the order of 2.5 km²with emissions differences of approximately 0.026μmol m⁻²s⁻¹. This suggests airborne approaches such as outlined here could be used to evaluate the impact of different agricultural practices at critical field‐size spatial scales.