Summary1. The performance of introduced plants can be limited by the availability of soil mutualists outside their native range, but how interactions with mutualists differ between ranges is largely unknown. If mutualists are absent, incompatible or parasitic, plants may compensate by investing more in root biomass, adapting to be more selective or by maximizing the benefits associated with the mutualists available. 2. We tested these hypotheses using seven non-agricultural species of Trifolium naturalized in New Zealand (NZ). We grew seeds from two native (Spain, UK) and one introduced (NZ) provenance of each species in glasshouse pots inoculated with rhizosphere microbiota collected from conspecifics in each region. 3. We compared how plant biomass, degree of colonization by rhizobia and arbuscular mycorrhizal fungi (AMF), and the growth benefit associated with each mutualist differed between provenances (native and introduced populations) when grown with soil microbiota from each region. We also tested whether the growth benefit of colonization by mutualists was correlated with the extent to which alien plants were distributed in the introduced range. 4. Rhizobia colonization was generally lower among introduced relative to native provenances. In NZ soils, 9% of all plants lacked rhizobia and 16% hosted parasitic nodules, whereas in native-range soils, there was no evidence of parasitism and all but one plant hosted rhizobia. Growth rates as a factor of rhizobia colonization were always highest when plants were grown in soil from their home range. Colonization by AMF was similar for all provenances in all soils but for four out of seven species grown in NZ soils, the level of AMF colonization was negatively correlated with growth rate. In general, introduced provenances did not compensate for lower growth rates or lower mutualist associations by decreasing shoot-root ratios. 5. Synthesis. Despite differences between introduced and native provenances in their associations with soil mutualists and substantial evidence of parasitism in the introduced range, neither level of colonization by mutualists nor the growth benefit associated with colonization was correlated with the extent of species' distributions in the introduced range, suggesting mutualist associations are not predictive of invasion success for these species.

Aim While plant species introduced to new regions may benefit from escaping natural enemies, their success may be impaired by losing key mutualists. We aimed to elucidate whether a selection of annual and perennial Trifolium (clover) species have lost associations with nitrogen-fixing bacteria (rhizobia) and arbuscular mycorrhizal fungi (AMF) in their introduced range.Location Introduced range in New Zealand (NZ) and native range in the United Kingdom (UK).Methods We compared the strain richness of rhizobia associated with five Trifolium species in both ranges using genetic fingerprinting (rep-PCR with ERIC primers). Phylogenetic analysis of the nodD gene was conducted to test for between-range differences in rhizobia genotypes associated with seven Trifolium species. We also used TRFLP to compare the richness of AMF associated with three Trifolium species in both ranges.Results Genetic fingerprinting indicated that Trifolium associate with a similar richness of rhizobia strains in NZ as they do in the UK. According to variation in the nodD gene, genotypes of rhizobia were indistinguishable between NZ and UK provenances. A total of 17 AMF operational taxonomic units were detected but there were no significant between-range differences in richness or in community structure.Main conclusions Contrary to general expectations regarding the loss of mutualists following species introduction, our findings suggest that alien plants, including those accidentally introduced, can have access to rich communities of soil-borne mutualists that are likely to facilitate successful naturalization.

Abstract1. Release from natural enemies is considered an important mechanism underlying the success of plants introduced to new regions, but the degree to which alien plant species benefit from enemy release appears highly variable and context-dependent. Such variation could arise if enemy release is a transient phenomenon, whereby alien plant species initially escape but subsequently accumulate enemies in their new regions.2. To evaluate this hypothesis in terms of soil biota, we used 11 Trifolium (clover) species introduced to New Zealand from Europe to test whether species resident for longer or with a larger geographic extent in New Zealand were more adversely affected by soil communities in the introduced range, as expected if species have accumulated inhibitory soil biota over time. We used plant-soil feedback (PSF) experiments to compare the effect of soil biota on the growth of the Trifolium species in soil from their introduced (New Zealand) and native (Spain and the United Kingdom) ranges. We applied a novel statistical approach aimed at isolating the impact of antagonistic soil biota by accounting for variation in plant growth due to mutualistic rhizobia bacteria.3. The between-range differences in PSF varied considerably among the Trifolium species: some species were released from inhibitory PSF in the introduced range, but the majority experienced similar PSF in both ranges. Averaged over all 11 Trifolium species, PSF was less inhibitory in the introduced than in the native range, implying some release from soil-borne enemies. However, neither residence time nor geographic extent in the introduced range was significantly correlated with the strength of release from inhibitory PSF. Synthesis.Our multispecies study provides some evidence that alien plants can escape antagonistic soil biota in their introduced range, but highlights how plant-soil feedback responses can be highly variable among congeneric plant species in the same region. Our results do not support the hypothesis that the release from inhibitory plant-soil feedback is transient, questioning the generality of this phenomenon. K E Y W O R D Salien, biological invasion, enemy release, exotic, invasion ecology, naturalisation, plant-soil (below-ground) interactions, soil biota, weed 208 | Journal of Ecology MCGINN et al.

When school buildings across the U.S. closed in March 2020 due to the COVID-19 pandemic, many school districts mobilized to establish emer­gency school meal programs to operate outside the setting of school cafeterias. The aim of this conver­gent mixed-methods study is to (a) examine the structure and rates of participation in the spring 2020 meal programs in Connecticut, and (b) obtain insight about the challenges, strategies used, and lessons learned during this time by food service leaders. We obtained quantitative data from the Connecticut State Department of Education and district websites, and qualitative data from nine one-hour interviews with school food service lead­ers. Although the National School Lunch Program provides meals at standard price, reduced-price, or no cost based on student household income, all emergency meals during spring 2020 were provided at no cost following the school closures resulting from the COVID-19 public health emergency dec­lara­tion. The average number of meals distrib­uted from March to May 2020 was significantly lower than the overall participation rates (i.e., paid, free, and reduced-price meals combined) prior to COVID-19. However, participation rates in April and May 2020 approached those of free and reduced-price meal participation a year earlier. Four key action themes emerged from the interviews: (1) tailor the program to community needs and resources; (2) identify strategies to facilitate partici­pation; (3) develop partnerships to coordinate school, municipal, and community efforts; and (4) establish programs that encourage resiliency. The interviewees also saw this event as an oppor­tunity to improve the perception of school meals. Inno­vations developed during the spring 2020 school building closures provide a road map for best prac­tices for the 2020–2021 school year and beyond.