top of page

COMMUNITY SCIENCE

WOOD BLOCK NATIVE BEE NESTS

Why do we make wood blocks?

By constructing a wood block, you offer a nesting option for solitary bees and wasps that prefer to nest in tunnels in solid wood. Incorporating a range of tunnels with depth (4-25 cm) and inside diameters (2-13 mm) will help to provide nest homes for the smallest and largest bees found locally. Using untreated wood are critical considerations for the success of the wood block as a nesting site. Your efforts contribute to providing diverse habitats for pollinators, supporting their populations and fostering biodiversity.By constructing a wood block, you offer a nesting option for solitary bees and wasps that prefer to nest in tunnels in solid wood. Incorporating a range of tunnels with depth (4-25 cm) and inside diameters (2-13 mm) will help to provide nest homes for the smallest and largest bees found locally. Using untreated wood are critical considerations for the success of the wood block as a nesting site. Your efforts contribute to providing diverse habitats for pollinators, supporting their populations and fostering biodiversity.

MATERIALS

What Kind of Bees Do You Want to Attract?

Similar Tunnel Size
Coffee stirrer
Drill Bit Size
3/32" - 1/8"
Masked Bees
Indside Dia of Nest
2.3 - 3.2 mm
Size
Small
Similar Tunnel Size
Coffee stirrer
Drill Bit Size
3/32" - 1/8"
Small Carpenter Bees
Indside Dia of Nest
2.3 - 3.2 mm
Size
Small
Similar Tunnel Size
Straw
Drill Bit Size
1/8" - 1/4"
Leaf Cutter Bees
Indside Dia of Nest
4 - 7 mm
Size
Medium
Similar Tunnel Size
Straw
Drill Bit Size
1/4" - 3/8"
Mason Bees
Indside Dia of Nest
7 - 10 mm
Size
Medium
Similar Tunnel Size
Boba straw
Drill Bit Size
3/8" - 1/2"
Carpenter Bees
Indside Dia of Nest
10-12 mm
Size
Large
  • Untreated, preservative-free lumber - 4x4 (10 cm x 10 cm) for blocks with shallower holes or a 4x6 (10 cm x 15 cm) for deeper holes.

  • Liner for protection and easy cleaning.

  • Drill with appropriate drill bits.

    • Backing board if drilling all the way through.

  • Overhanging roof for additional shelter.

  • Mounting materials

INSTRUCTIONS

1. On one side of the block, drill a series of nest holes with appropriate sizes and depths.

Follow chart above to choose diameter of holes.

 

Maintain a separation of at least 3/4 inch (19 mm) from center to center and avoid placing holes too close to the edges.

Drill a minimum depth of 3 in (8 cm) but experiment with hole depths, as deeper holes may attract female bees or wasps.

2. Attach an overhanging roof to provide additional shelter from rain.

3. Decorate the outside of the block.

 

Anecdotal evidence suggests that dark nest blocks are attractive to bees, but feel free to experiment with colors.

4. Securely mount the block to prevent movement or shaking in the wind, as this can disrupt nesting and larval development.

Experiment with different heights from the ground to determine preferences within your local. pollinator community.

5. Observe the nesting behavior and success of pollinators using the block.

TIPS FOR MONITORING& MAINTAINING

  • Placement

    • Locate a nest site in an area that receives morning sunlight.

    • Mount the nest site on a secure structure, such as a post or a wall, at eye level.

  • Regular Inspections

    • Check the nest site periodically to ensure it's in good condition.

    • Look for signs of occupancy, such as sealed tubes, and note the diversity of species using the site.

  • Cleaning

    • Clean the nesting tubes during the winter or early spring when bees are not actively using them.

    • Replace old or damaged tubes with new ones.

  • Protection from Predators

    • Consider adding mesh or other protective barriers to prevent predators from accessing the nest site.

  • Provide a Water Source

    • Ensure there is a nearby water source for the bees to access for drinking and mud collection.

  • Plant Native Flora

    • Surround the nest site with a variety of native plants to provide food sources for the solitary bees.

Nesting Behavior

Some bees and wasps nest in cavities in solid wood created by woodpeckers, beetles and other animals. Species like Megachile angelarum partition cells in tunnels with collected gums and resins from plants. Species like Megachile rotundata partition cells in tunnels with collected leaves. Wood blocks can serve as nesting sites for species local to you with similar nesting habits.

Let’s make some wood block native bee homes!

bottom of page