{"id":3373,"date":"2020-06-02T00:15:01","date_gmt":"2020-06-02T07:15:01","guid":{"rendered":"https:\/\/depts.washington.edu\/hortlib\/pal\/pal-question-1043\/"},"modified":"2026-01-14T10:03:04","modified_gmt":"2026-01-14T18:03:04","slug":"grass-carrying-wasps","status":"publish","type":"pal","link":"https:\/\/depts.washington.edu\/hortlib\/pal\/grass-carrying-wasps\/","title":{"rendered":"Grass-carrying wasps"},"content":{"rendered":"

Who has moved into the tubes in my mason bee house? There are these strange bundles that seem to have dead crickets entombed in them. Do I need to remove them?<\/strong><\/p>\n

 <\/p>\n

Your description and photos convince me that these bundles were made by grass-carrying wasps (Isodontia species)<\/a> who store food (such as crickets!) with their cocoons to nourish the larvae when they emerge. Your mason bee house was a convenient location to nest. They look for any hollow cavities<\/a> (such as stems, trees, or even window tracks), and the mason bee tubes were a perfect spot.<\/p>\n

They would have built the nest in early summer<\/a>, emerging later (late July through September) to visit flowers for pollen and nectar.<\/p>\n

Grass-carrying wasps are beneficial insects just like mason bees, and serve as pollinators, too. This article<\/a> from Heather Holm’s Restoring the Landscape with Native Plants (author of Bees: An Identification and Native Plant Forage Guide<\/a>, 2017) mentions them visiting Solidago, Eupatorium<\/em>, and Plantago. <\/em><\/p>\n

As far as removing the grass-shrouded crickets or katydids, I would follow your normal mason bee housecleaning schedule. Usually, cleaning the tubes would be done between October and December. This page from David Suzuki’s web page<\/a> describes the process.<\/p>\n

If you are curious to see a grass-carrying wasp in action, entomologist Michael Raupp’s Bug of the Week<\/a> page includes a video of a wasp creating its nest.<\/p>\n

Beneficial insects<\/a>, <\/span>Grass-carrying wasps<\/a>, <\/span>Honeybees and pollinators<\/a><\/div>\n","protected":false},"excerpt":{"rendered":"

Who has moved into the tubes in my mason bee house? There are these strange bundles that seem to have dead crickets entombed in them. Do I need to remove them?   Your description and photos convince me that these bundles were made by grass-carrying wasps (Isodontia species) who store food (such as crickets!) with their cocoons to nourish the larvae when they emerge. Your mason bee house was a convenient location to nest. They look for any hollow cavities…<\/p>\n

Continue reading Grass-carrying wasps<\/span><\/a><\/div>\n","protected":false},"author":4,"featured_media":0,"menu_order":0,"template":"","keyword":[157,1044,310],"class_list":["post-3373","pal","type-pal","status-publish","hentry","keyword-beneficial-insects","keyword-grass-carrying-wasps","keyword-honeybees-and-pollinators"],"acf":[],"_links":{"self":[{"href":"https:\/\/depts.washington.edu\/hortlib\/wp-json\/wp\/v2\/pal\/3373"}],"collection":[{"href":"https:\/\/depts.washington.edu\/hortlib\/wp-json\/wp\/v2\/pal"}],"about":[{"href":"https:\/\/depts.washington.edu\/hortlib\/wp-json\/wp\/v2\/types\/pal"}],"author":[{"embeddable":true,"href":"https:\/\/depts.washington.edu\/hortlib\/wp-json\/wp\/v2\/users\/4"}],"wp:attachment":[{"href":"https:\/\/depts.washington.edu\/hortlib\/wp-json\/wp\/v2\/media?parent=3373"}],"wp:term":[{"taxonomy":"keyword","embeddable":true,"href":"https:\/\/depts.washington.edu\/hortlib\/wp-json\/wp\/v2\/keyword?post=3373"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}