Polistes species are commonly known as paper nest wasps because they make their nests from grey wood fibre mixed with saliva. The diet is primarily lepidopteran larvae and small spiders which is carried back to the nest and 'carved up' for feeding to the queen and larvae. P. humilis appears to be a common pollinator becaus eof its abundance, but credible scientific studies are needed to confirm the species pollination efficiency.
Thank you Graham -haven’t located the nest but good to know this is a native species as there is an increasing presence in the region of the Asian Paper wasp.