Osmia lignaria

A species of solitary bee known for its role in pollination.

Overview

Osmia lignaria, commonly known as the blue orchard bee or orchard mason bee, is a species of solitary bee native to North America. These bees are highly valued for their role in pollinating fruit trees, particularly in orchards. Unlike social bees such as the honey bee, Osmia lignaria does not form colonies but instead nests individually.

Description

Osmia lignaria is characterized by its metallic blue or greenish-blue coloration. The females are slightly larger than the males, measuring about 10 to 12 millimeters in length. These bees have robust bodies and are covered with fine hairs that aid in the collection of pollen.

Life Cycle

The life cycle of Osmia lignaria begins in early spring when the adults emerge from their cocoons. The females immediately start searching for suitable nesting sites, which are often pre-existing cavities such as holes in wood or hollow stems. Once a site is chosen, the female collects mud to construct partitions and seal the entrance of the nest.

Nesting Behavior

File:Osmia lignaria nest.jpg

A female Osmia lignaria constructing her nest in a wooden block.

Each nest consists of several cells, each containing a single egg. The female provisions each cell with a mixture of pollen and nectar, which serves as food for the developing larva. After laying an egg on the pollen mass, she seals the cell with mud and continues to the next one.

Pollination

Osmia lignaria is an efficient pollinator, particularly for early-blooming fruit trees such as apple, pear, and cherry. These bees are active in cooler temperatures and can fly in conditions that are less favorable for other pollinators. Their foraging behavior, which involves visiting multiple flowers in a short period, makes them highly effective at transferring pollen.

Habitat

These bees are commonly found in temperate regions across North America. They prefer habitats that provide ample nesting sites and a rich supply of flowering plants. Gardens, orchards, and forest edges are ideal environments for Osmia lignaria.

Conservation

The conservation of Osmia lignaria is important due to their role in pollination. Providing artificial nesting sites, such as bee hotels, and planting a variety of flowering plants can help support their populations. Avoiding the use of pesticides is also crucial to their survival.

Related pages

• Pollination
• Bee
• Solitary bee
• Honey bee