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Here we describe the nesting behavior of a previously unstudied solitary groundnesting wasp, Ammophila boharti Menke, 1964. Species in the genus Ammophila are of particular interest because they exhibit a variety of parental care strategies. Ammophila boharti wasps were observed at two California field sites, one in the Mojave Desert and the other at the Antioch Dunes National Wildlife Refuge. Ammophila boharti begins its nesting cycle by hunting for a single, large caterpillar; all prey observed at Antioch Dunes were Neoterpes ephelidaria (Hulst, 1886) (Lepidoptera: Geometridae), which were feeding on California poppies, Eschscholzia californica Cham. (Papaveraceae). Female A. boharti wasps sting the caterpillar, inducing permanent paralysis, and then cache the prey off the soil surface on a plant while they excavate a shallow, unicellular nest. The caterpillar is then placed in the nest, a single egg laid on the caterpillar, and a permanent closure placed on the nest. No nest parasites were seen at any stage of the nesting process, and offspring within all excavated nests developed successfully through the larval stages to spin cocoons. Thus, this species exhibits a 'prey-nest' sequence of nesting behavior with almost no contact between the mother and her offspring, a minority condition within the genus. [ABSTRACT FROM AUTHOR]

Carbon addition has been proposed as an alternative to herbicide and manual removal methods to treat non‐native plants and reduce non‐target effects of treatments (e.g. impacts on native plants; surface disturbance). On Mojave Desert pavement and biocrust substrates after experimental soil disturbance and carbon addition (1,263 g C/m2 as sucrose), we observed declines in lichens and moss cover in sucrose‐treated plots. To further explore this unforeseen potential side effect of using carbon addition as a non‐native plant treatment, we conducted biocrust surveys 5 and 7 years after treatments, sampled surface soils to observe if treatments additionally affected soil filamentous cyanobacteria, and conducted laboratory trials testing the effects of different levels of sucrose on cyanobacteria and desert mosses. Sucrose addition to biocrust plots reduced lichen and moss cover by 33–78% and species richness by 40–80%. Sucrose reduced biocrust cover in biocrust plots to levels similarly detected in pavement plots (<1%). While cyanobacteria in the field did not appear to be affected by sucrose, laboratory tests showed negative effects of sucrose on both cyanobacteria and mosses. Cyanobacteria declined by 41% 1 month after exposure to 5.4 g C/m2 equivalent solutions. We detected injury to photosynthesis in mosses after 96 hour exposure to 79–316 g C/m2 equivalent solutions. Caution is warranted when using carbon addition, at least in the form and concentration of sucrose, as a treatment for reducing non‐native plants on sites where conserving biocrust is a goal. [ABSTRACT FROM AUTHOR]