About Cavity-Nesting Native What is a Cavity-Nesting ? Providing Habitat for Cavity-Nesting Bees

NY

Of the roughly 430 native bees that have been identified in New York State, there are a group of bees that are known as cavity-nesting bees. These You can help native bees by filling your garden species nest in cavities that can be found in old with native plants and by creating hotels. logs or dried plant stems that have holes in them. An important step in helping these essential is providing food and habitat space. Below Is a List of Six Common Cavity-Nesting Bees That Can Befound actual size at the O’Hara Nature Center

Entrance hole Cavity-nesting bees come in many different shapes and sizes, so the size of the hole will determine what type of bee will take up residency in their pollinator hotel. Small Carpenter Bees Masked Bees Are Cavity-Nesting Bees Agressive?

Mason Bees Bellflower Resin Bees

Cavity-nesting bees are not aggressive. Unlike bees that live in colonies, like the European bee and our own native bumble bee, most are solitary. They do not produce honey or have a large colony to protect. However, if a cavity-nesting bee is provoked, it does possess the ability to sting. Blue Orchard Bees Leafcutter Bees The O’Hara Nature Center What’s Happening Inside My Pollinator Hotel?

Example of repurposed birdhouse as a Pollinator Hotel Dimensions: W= 5”, H= 9”, INT= 5 by 5”

Example of a cavity-nesting Example of a cavity-nesting bee’s nest entrance bee searching for the sealed with soil appropriate sized hole

Example of stored Example of newly laid Mason as food for the larvae Bee egg in stem cavity as they develope

Leafcutter Bee Even though cavity-nesting bees Mason Bee emerging carrying a piece of a leaf to lay their brood in solitary cavitites, from its nest 24-days later use for nesting material they can take up residency next to other cavity-nesting bees

Page The O’Hara Nature Center 2 Identification of Common Cavity-Nesting Bees

Drill Hole Diameter Cavity-Nesting Native *Actual Bee Bit Size in mm Bees Expected Size Identification

1/8” 3 Small (Genus: Ceratina) 11/64” 4.5

13/64” 5 Masked Bee (Genus: Hylaeus) 9/32” 7

7/32” 5.6 Mason Bee (Osmia sp.) 3/8” 9.5

19/64” 7.5 Bellflower Resin Bee ( campanulae) 25/64” 10

23/64” 9 Blue Orchard Bee (Osmia lignaria) 7/16” 11

13/64” 5

Leafcutter Bee (Megachile sp.) 15/16” 24

Page The O’Hara Nature Center 3 Identification of Common Cavity-Nesting Bees

Photo Size Preferred Materials Additional Information

Small carpenter bees are Pre-drilled wood blocks, important of plants. small hollow twigs, and Due to their size, they can stems enter small-mouthed flowers unreachable by larger bees. Small Carpenter Bees 3 - 4.5 mm long Reed grasses, pre-drilled The Masked Bees’ bodies are wood blocks and hollow almost entirely black except for twigs, and hollow stems from pale patches on their heads sunflower (Helianthus), Joe and legs. These bees are Pye weed (Eutrochium sparsely covered in hairs, purpureum), and goldenrod giving them a wasp-like Masked Bees 5 - 7 mm long () appearance. Pre-drilled wood blocks, When building their nests, hollow twigs, and hollow Mason Bees use clay to make stems from sunflower (Heli- partitions and to seal the anthus ), Joe Pye weed entrance. This unique (Eutrochium purpureum), mud-building behavior leads and goldenrod (Solidago) to their common designation Mason Bees 5.6 - 9.5 mm long as “masons”. The Bellflower Resin Bees collect sticky plant and tree Pre-drilled wood blocks, resins, which they use to seal small to large hollow twigs the egg chambers of their and stems nests. These native bees construct nests in hollow plant Bellflower Resin Bees 7.5 - 10 mm long stems or in tunnels left in wood. Blue Orchard Bee season is early spring. Once they emerge, Pre-drilled wood blocks, they promptly mate, search for small to large hollow twigs empty holes that are the right and stems size and go to work stocking their nests. A favorite food for Blue Orchard Bees 8.5 - 13 mm long their brood is fruit tree pollen. Leafcutter Bees get their name from the female’s behavior of Pre-drilled wood blocks, cutting out round pieces of small to large hollow twigs leaves, which they use to line and stems their nests. They nest in preexisting holes in wood Leafcutter Bees 5 - 24 mm long created by other . Page The O’Hara Nature Center 4 Identification of Common Cavity-Nesting Bees Wood Hollow Stem Plant Bee Hole Diameter *Actual Nesting Nesting Stem Identification in mm Size Example Example Materials Goldenrod 1/8” 3 Sunflowers Reed grass Joe Pye 11/64” 4.5 Weed Small Carpenter Bees Milk Weed Goldenrod 13/64” 5 Sunflowers Reed grass Joe Pye 9/32” 7 Weed Masked Bees Milk Weed Goldenrod 7/32” 5.6 Sunflowers Reed grass Joe Pye 3/8” 9.5 Weed Mason Bees Milk Weed Joe Pye 19/64” 7.5 Weed Japanese Knotweed 25/64” 10 Bamboo Bellflower Resin Bees Shoots Joe Pye 21/64” 8.5 Weed Japanese Knotweed 33/64” 13 Bamboo Blue Orchard Bees Shoots Joe Pye 13/64” 5 Weed Japanese Knotweed 15/16” 24 Bamboo Leafcutter Bees Shoots Page The O’Hara Nature Center 5