Editing Fruit tree pollination (section)

==Temperate fruits==

===Apples===

Most [[apple]] plants/trees are [[Self-incompatibility in plants|self-incompatible]], that is, they do not produce fruit when pollinated from a flower of the same tree or from another tree of the same [[cultivar]], and must be [[cross pollination|cross pollinated]]. A few are described as "self-fertile" and are capable of self-pollination, although even those tend to carry larger crops when cross pollinated from a suitable [[pollenizer]]. A relatively small number of [[cultivars]] are "triploid", meaning that they provide almost no viable pollen for themselves or other apple trees. Apples that can pollinate one another are grouped by the time they flower so cross-pollinators are in bloom at the same time. [[Pollination management]] is an important component of apple culture. Before planting, it is important to arrange for pollenizers – varieties of apple or [[malus|crabapple]] that provide plentiful, viable and compatible [[pollen]]. Orchard blocks may alternate rows of compatible varieties, or may plant crabapple [[tree]]s, or [[grafting|graft]] on [[branch|limbs]] of crabapple. Some varieties produce very little pollen, or the pollen is [[infertility|sterile]], so these are not good pollenizers. Good-quality [[Nursery (horticulture)|nurseries]] have pollenizer compatibility lists. Growers with old orchard blocks of single [[Variety (biology)|varieties]] sometimes provide bouquets of crabapple [[blossom]]s in [[Drum (container)|drums]] or [[bucket|pails]] in the orchard for pollenizers. Home growers with a single tree and no other variety in the [[Neighbourhood|neighborhood]] can do the same on a smaller scale.

During the bloom each season, commercial apple growers usually provide [[pollinator]]s to carry the pollen. [[Honeybee]] [[Beehive (beekeeping)|hives]] are most commonly used in the United States, and arrangements may be made with a commercial [[beekeeper]] who supply hives for a fee. Honeybees of the genus [[Honey bee|''Apis'']] are the most common pollinator for apple trees, although members of the genera ''[[Andrena]]'', ''[[Bombus]]'', ''[[Halictus]]'', and ''[[Osmia]]'' pollinate apple trees in the wild.<ref name="McGregor" />  [[Solitary bee]]s or wild bees such as ground-nesting mining bees (''Andrena'') may play a far bigger role in pollination than at one time suspected,<ref>{{cite journal |journal=Journal of the New York Entomological Society |volume=114 |issue=1 & 2 |pages=86–91 |year=2006 |doi=10.1664/0028-7199(2006)114[86:NOTNBP]2.0.CO;2 |title=Notes on the Native Bee Pollinators in New York Apple Orchards |author1=K. E. Gardner |author2=J. S. Ascher}}</ref> and are alternative pollinators in orchards.<ref>Biddinger D, Rajotte E, Joshi NK, Ritz A. Wild bees as alternative pollinators. ''Fruit Times''. 2011,30(9):1–4.</ref>  [[Bumble bee]]s are sometimes present in orchards, but not usually in enough quantity to be significant pollinators; in the home garden with only a few trees, their role may be much greater. Apple growers also rely on several species of wild bees for pollination in their orchard.<ref>{{Cite journal|last1=Park|first1=M.G.|last2=Joshi|first2=N. K.|last3=Rajotte|first3=E. G.|last4=Biddinger|first4=D. J.|last5=Losey|first5=John E.|last6=Danforth|first6=Bryan N.|date=2018-04-25|title=Apple grower pollination practices and perceptions of alternative pollinators in New York and Pennsylvania|journal=Renewable Agriculture and Food Systems|volume=35 |pages=1–14|doi=10.1017/s1742170518000145|issn=1742-1705|doi-access=free}}</ref><ref>Joshi, N. K., D. Biddinger, and E. G. Rajotte. "A survey of apple pollination practices, knowledge and attitudes of fruit growers in Pennsylvania." In ''10th International Pollination Symposium, Puebla, Mexico''. 2011.</ref>

Increasingly [[Orchard bee]]s (spring mason bees, genus ''Osmia'') are being used in fruit tree pollination.<ref>{{Cite journal|last1=Sheffield|first1=Cory S.|last2=Westby|first2=Sue M.|last3=Smith|first3=Robert F.|last4=Kevan|first4=Peter G. |date=September 2008|title=Potential of bigleaf lupine for building and sustaining Osmia lignaria populations for pollination of apple|journal=The Canadian Entomologist |volume=140 |issue=5 |pages=589–599 |doi=10.4039/n08-011 |issn=0008-347X|hdl=10214/2430|hdl-access=free}}</ref> According to British writer Christopher O'Toole in his book ''The Red Mason Bee'', ''[[Osmia rufa]]'' is a much more efficient pollinator of orchard crops (in Europe) than honey bees.<ref>{{cite book |author=Christopher O'Toole |title=The Red Mason Bee |publisher=Osmia Publications |year=2000 |isbn=0-9539906-8-0}}</ref> Both ''O. rufa'' and ''[[Osmia cornuta|O. cornuta]]'' are used in Europe, while in western North America, the "Blue Orchard Bee" (''[[Osmia lignaria]]'', more black than blue in color) is a proven orchard pollinator.<ref>{{cite book |last1=Bosch |first1=Jordi |last2=Kemp |first2=William P. |year=2001 |title=How to Manage the Blue Orchard Bee |url=https://www.ars.usda.gov/ARSUserFiles/np305/blue_orchard_bee.pdf |publisher=Sustainable Agriculture Network |isbn=1-888626-06-2 |access-date=2018-04-10}}</ref> In [[Japan]], the Japanese Orchard Bee—the [[hornfaced bee]], ''[[Osmia cornifrons]]''—provides up to 80% of the apple pollination.<ref>{{cite web |url=http://extension.psu.edu/plants/tree-fruit/news/2013/the-role-of-pollen-bees-in-fruit-tree-pollination-and-some-new-cautions-on-pesticide-use |title=The Role of Pollen Bees in Fruit Tree Pollination and Some New Cautions on Pesticide Use |author1=D. Biddinger |author2=A. Ritz |author3=E. Rajotte |author4=N. Joshi |date=August 23, 2013 |publisher=Penn State College of Agricultural Sciences |url-status=dead |archive-url=https://web.archive.org/web/20160701194700/http://extension.psu.edu/plants/tree-fruit/news/2013/the-role-of-pollen-bees-in-fruit-tree-pollination-and-some-new-cautions-on-pesticide-use |archive-date=2016-07-01}}</ref>
Beyond Japan, ''Osmia cornifrons'' is also used increasingly in the eastern US, because like other mason bees it is up to 100 times more efficient than the honeybee—a mere 600 hornfaced bees being required per hectare, as opposed to tens of thousands of honeybees.<ref>{{cite web |url=http://www.pollinatorparadise.com/solitary_bees/Solitar.htm |title=Solitary Bees For Orchard Pollination |author=Suzanne W. T. Batra |date=April 1997 |website=Pollinator Paradise}}</ref> Home growers may find these more acceptable in suburban locations because they rarely [[Sting (biology)|sting]].

Symptoms of inadequate pollination are small and misshapen apples, and slowness to [[ripening|ripen]]. The [[seed]]s can be counted to evaluate pollination. Well-pollinated apples have best quality, and will have seven to ten seeds.<ref name="Hartman">{{cite journal|last1=Hartman|first1=Fred|last2=Howlett|first2=Freeman|title=Fruit setting of the delicious apple|journal=Ohio Agricultural Experiment Station|date=1954|issue=745|page=64}}</ref> Apples with fewer than three seeds will usually not mature and will drop from the trees in the early [[summer]].  Inadequate pollination can result from either a lack of pollinators or pollenizers, or from poor pollinating [[weather]] at bloom time.<ref>{{cite journal|last1=Sheffield|first1=Cory|title=Pollination, Seed Set and Fruit Quality in Apple: Studies with Osmia Lignaria (Hymenoptera: Megachilidae) in the Annapolis Valley, Nova Scotia, Canada|journal=Journal of Pollination Ecology|date=February 2014|volume=12|issue=13|pages=120–128|doi=10.26786/1920-7603(2014)11 |url=http://www.pollinationecology.org/index.php?journal=jpe&page=article&op=download&path%5B%5D=229&path%5B%5D=89}}</ref> Multiple bee visits are usually required to deliver sufficient grains of pollen to accomplish complete pollination.

===Pears===

Like apples, [[pear]]s are self-incompatible and need to attract insects in order to be pollinated and produce fruit.<ref name="Abrol" /> One notable difference from apples is that pear blossoms are much less attractive to honeybees due to their pale coloring and light odor. Bees may abandon the pear blossoms to visit dandelions or a nearby apple orchard. The majority of pollinators of pear trees are [[honey bee]]s, although pears are also visited by [[blow flies]] and [[hoverfly|hoverflies]].<ref name="Abrol" /> In some areas, such as the [[Emilia-Romagna]] area of Italy, honeybees could not be used to pollinate pears due to the spread of [[fireblight]] in the 1990s, and ''[[Osmia cornuta]]'' were used as pollinators instead.<ref>{{cite journal |title=Osmia cornuta (Hymenoptera, Megachilidae) as a pollinator of pear (Pyrus communis): fruit- and seed-set |journal=Apidologie |year=2003 |last1=Maccagnani |first1=Bettina |last2=Ladurner |first2=Edith |last3=Santi |first3=Fabrizio |last4=Burgio |first4=Giovanni |volume=34 |issue=3 |pages=207–216 |doi=10.1051/apido:2003009 |url=https://www.apidologie.org/articles/apido/pdf/2003/03/M3209.pdf |accessdate=2021-08-27 }}</ref> A way to combat the low attraction of honey bees to pear blossoms is to use bee attractants to entice the bees to pollinate the flowers.Bee attractants may include [[List of honey bee pheromones|pheromones]] that mimic the brood pheromone or the juvenile pheromone, or other attractants.{{cn|date=September 2021}} There are also other methods for attracting honey bees to pear blossoms. One is [[saturation pollination]], that is to stock so many bees that all area blossoms are worked regardless of the attractiveness to the bees. Another method is to delay the movement of the beehives into the orchards until there is about 30 percent bloom. The bees are moved into the orchard during the night and will usually visit the pear blossoms for a few hours until they discover the richer nectar sources. The recommended number of hives per acre is one.

===Plums and prunes===

Most Asian plums require a second variety for cross-pollination, whereas most European plums are self-fertile. European plums that dry well are also called prunes, the common name for the dry fruit. Several of the Asian plums bloom early and pollinator management is similar to apricots. However the fruiting wood especially of Asian plums can be brittle and over-pollination requires aggressive thinning of fruits.

===Apricots===

Apricots are botanically similar to [[almond]]s and like almonds they can bloom early, making pollinator management similar except that a tree can overcrop if the fruit is not thinned.

===Peaches and Nectarines===

Most peaches and nectarines are self fertile and thus require fewer pollinators than apples and pears. 

===Cherries===
Pie cherries, also called sour cherries, are self-fertile. In some varieties, fruit yield could increased by utilizing pollinators.<ref>{{Cite journal|last1=Biddinger|first1=D. J.|last2=Joshi|first2=N. K.|last3=Rajotte|first3=E. G.|last4=Halbrendt|first4=N. O.|last5=Pulig|first5=C.|last6=Naithani|first6=K. J.|last7=Vaughan|first7=M.|date=2013-08-01|title=An immunomarking method to determine the foraging patterns of Osmia cornifrons and resulting fruit set in a cherry orchard|journal=Apidologie|volume=44|issue=6|pages=738–749|doi=10.1007/s13592-013-0221-x|issn=0044-8435|url=https://hal.archives-ouvertes.fr/hal-01201342/file/13592_2013_Article_221.pdf}}</ref>  Most sweet cherries need a second variety for pollination, and even self-fertile varies have improved fruit-set with a second variety. Pie cherries can pollinate sweet cherries. Cherries do not need thinning.

===Figs===

Some [[Fig|figs]] produce fruit without pollination. Figs that are pollinated rely on [[fig wasp]]s.