Megachilidae: Leafcutter Bees (Megachile)

categories: Bees Megachilidae Pollinators

last review date: 2026-04-26 08:28

Leafcutter bee on purple flower.
Leafcutter Bee (Megachile sp.)
Photo by: D. James

Biology

Leafcutter bees are solitary bees, and as their name suggests, cut 0.25-0.5 inch circular pieces of leaves or petals from which to construct their brood cells in rotting wood, stems and soil.

They construct cigar-like nests that contain several cells. Each cell contains a ball of stored pollen and a single egg and therefore produces a single bee.

Leafcutter bees are moderate to large bees (0.4-0.8 inches long) with about 140 species in North America. The females carry pollen on a patch of dry hair on the underside of the abdomen.

Attracting and Keeping Natural Enemies
and Pollinators in Your Yard and Garden

  • Avoid regular use of synthetic, broad-spectrum pesticides.
  • Infrequent use of certain narrow-spectrum pesticides is more compatible with some beneficials but generally the less chemical inputs there are, the greater and more diverse the beneficial insect community will be.
  • Extensive lawns are also not conducive to attracting and retaining a diversity of beneficial insects, mites and spiders. Minimize lawn areas and maximize shrub and bush plantings.
  • Many beneficials reside naturally in riparian and other ‘natural’ areas near to many back yards. Natural dispersion from these refuges ensures that some beneficials will visit back yards but they will not stay unless food, host and shelter resources are available.
  • Native plants have closer affinities with native insects and therefore provide most of these resources. A garden with a good diversity of local native flora in and around back yards, will improve the abundance and diversity of local, beneficial arthropods.
  • Native flora also provides natural overwintering sites for many beneficial insects and it is useful to leave at least a small area of native vegetation undisturbed during fall and winter.
  • Some kinds of beneficial insects (e.g. lady beetles, lacewings, predatory mites) are available for purchase from commercial suppliers. However, benefits from introducing these beneficials are usually limited and short-lived. Upon release, commercially obtained lady beetles and lacewings often disperse and may rapidly leave your backyard despite the presence of prey and suitable nectar resources. Generally, it is more effective and sustainable to create a garden habitat that will be colonized by beneficials naturally.

Chemical Management

IMPORTANT: Visit Home and Garden Fact Sheets for more information on using pesticides.

  • None recommended


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Evidence of noncompliance may be reported through your local Extension office.