Pollination of fruit trees is required to produce seeds with surrounding fruit. It is the process of moving pollen from the anther to the stigma, either in the same flower or in another flower. Some tree species, including many fruit trees, do not produce fruit from self-pollination, so pollinizer trees are planted in orchards.
Megachile rotundata, the alfalfa leafcutting bee, is a European bee that has been introduced to various regions around the world. As a solitary bee species, it does not build colonies or store honey, but is a very efficient pollinator of alfalfa, carrots, other vegetables, and some fruits. Because of this, farmers often use M. rotundata as a pollination aid by distributing M. rotundata prepupae around their crops. Each female constructs and provisions her own nest, which is built in old trees or log tunnels. Being a leafcutter bee, these nests are lined with cut leaves. These bees feed on pollen and nectar and display sexual dimorphism. This species has been known to bite and sting, but it poses no overall danger unless it is threatened or harmed, and its sting has been described as half as painful as a honey bee's.
Megachilidae is a cosmopolitan family of mostly solitary bees. Characteristic traits of this family are the restriction of their pollen-carrying structure to the ventral surface of the abdomen, and their typically elongated labrum. Megachilid genera are most commonly known as mason bees and leafcutter bees, reflecting the materials from which they build their nest cells ; a few collect plant or animal hairs and fibers, and are called carder bees, while others use plant resins in nest construction and are correspondingly called resin bees. All species feed on nectar and pollen, but a few are kleptoparasites, feeding on pollen collected by other megachilid bees. Parasitic species do not possess scopae. The motion of Megachilidae in the reproductive structures of flowers is energetic and swimming-like; this agitation releases large amounts of pollen.
Osmia lignaria, commonly known as the orchard mason bee or blue orchard bee, is a megachilid bee that makes nests in natural holes and reeds, creating individual cells for its brood that are separated by mud dividers. Unlike carpenter bees, it cannot drill holes in wood. O. lignaria is a common species used for early spring fruit bloom in the United States and Canada, though a number of other Osmia species are cultured for use in pollination.
Osmia cornifrons, also known as the horned-face bee, is a species of solitary bee indigenous to Northern Asia. Physically, this species of bee is recognized for its horn-like extensions originating from its lower face. Populations of O. cornifrons have been recorded in multiple locations, including Japan, Korea, China, and Russia. O. cornifrons are more docile as compared to other species of bees and are less prone to sting when aggravated.
Osmia californica is a megachilid bee, or mason bee. Native to North America, the mason bees are important pollinators, with O. california pollinating over 33 genera from 13 plant families. O. californica generally emerges a little later in the spring than the better known orchard mason bee. Like the orchard mason bee, O. californica is a solitary nester, usually constructing nests with leaf pulp providing a partition within the nest to protect the egg chamber.
Osmia bicornis is a species of mason bee, and is known as the red mason bee due to its covering of dense gingery hair. It is a solitary bee that nests in holes or stems and is polylectic, meaning it forages pollen from various different flowering plants. These bees can be seen aggregating together and nests in preexisting hollows, choosing not to excavate their own. These bees are not aggressive; they will only sting if handled very roughly and are safe to be closely observed by children. Females only mate once, usually with closely related males. Further, females can determine the sex ratio of their offspring based on their body size, where larger females will invest more in diploid females eggs than small bees. These bees also have trichromatic colour vision and are important pollinators in agriculture.
Anthidium manicatum, commonly called the European wool carder bee, is a species of bee in the family Megachilidae, the leaf-cutter bees or mason bees.
Osmia avosetta is a species of mason bee. It is solitary by nature, and is notable for its distinctive use of flower petals to construct nests for its larvae.
Megachile angelarum is a species of bee in the Megachilidae family.
Coelioxys, common name leaf-cutting cuckoo bees or sharp-tailed bees, is a genus of solitary kleptoparasitic cuckoo bees belonging to the family Megachilidae.
Megachile melanophaea is a species of leaf-cutter bee in the family Megachilidae. It was first described by the British zoologist Frederick Smith in 1853. It is native to North America.
Megachile texana, the Texas leafcutter bee, is a species of bee in the family Megachilidae. It was first described by the American entomologist Ezra Townsend Cresson in 1878. It is native to the United States and southern Canada.
Macropis nuda is a ground nesting, univoltine bee native to northern parts of North America. Thus, this species cocoons as pupae and hibernates over the winter. The species is unusual as it is an oligolectic bee, foraging exclusively for floral oils and pollen from Primulaceae of the species Lysimachia ciliata.
Osmia uncinata, the pinewood mason bee, is a species of solitary bee from the family Megachilidae It is an Arctic-alpine species which is found in the northern Palearctic, in the United Kingdom it is a Biodiversity Action Plan priority species.
Osmia caerulescens, the blue mason bee, is a species of solitary bee from the family Megachilidae. It has a Holarctic distribution extending into the Indomalayan region, although its presence in the Nearctic may be due to human-assisted introduction.
Osmia inermis, the mountain mason bee , is a species of mason bee from the family Megachilidae which has a Holarctic distribution.
Chaetodactylus is a genus of parasitic mite primarily associated with solitary bees with over 20 species.
Chaetodactylus krombeini was described by Karl Krombein and E. W. Baker in the 1960s. The mites are about 0.5 mm across, with the females larger than the males. Pollen mites are a kleptoparasitic pest of Megachilid solitary bees, with Ch. krombeini found with Osmia lignaria of North America,. Pollen mites do not feed on bees, but rather their provisions, and are harmful because they consume the food resources and starve or stunt the developing larvae; there is evidence that pollen mites also directly harm the egg by puncturing it.
Osmia nigriventris, also known as the large black-bellied mason bee, is a species of solitary bee within the family Megachilidae.
