Editing Oat (section)

== Agronomy ==

=== Cultivation ===

Oats are [[annual plant]]s best grown in [[temperate]] regions.<ref name="RBGKew"/> They tolerate cold winters less well than wheat, rye, or barley; they are harmed by sustained cold below {{convert|20|F|C|order=flip}}.<ref>{{cite web |last=Bliss |first=Rosalie Marion |title=Hardy Oats Stand the Cold |url=https://www.ars.usda.gov/news-events/news/research-news/2005/hardy-oats-stand-the-cold/ |publisher=USDA Agricultural Research Service |access-date=21 July 2024 }}</ref> They have a lower summer heat requirement and greater tolerance of (and need for) rain than the other cereals mentioned, so they are particularly important in areas with cool, wet summers, such as Northwest Europe.<ref name="RBGKew"/><ref>{{cite web |title=Oat Growth Guide |url=https://www.hutton.ac.uk/sites/default/files/files/publications/Oat-Growth-Guide.pdf |publisher=[[Quaker Oats Company|Quaker]] |access-date=2 May 2024 }}</ref>

Oats can grow in most fertile, drained soils, being tolerant of a wide variety of soil types. Although better yields are achieved at a soil pH of 5.3 to 5.7, oats can tolerate soils with a pH as low as 4.5. They are better able to grow in low-nutrient soils than wheat or maize, but generally are less tolerant of high soil salinity than other cereals.<ref>{{cite book |last=Forsberg |first=Robert A. |title=The Oat Crop |date=1995 |publisher=[[Chapman & Hall]] |isbn=978-0-412-37310-7 |location=Suffolk |pages=223–224 }}</ref> Traditionally, US farmers grew oats alongside [[red clover]] and [[alfalfa]], which fixed nitrogen and provided animal [[forage]]. With less use of horses and more use of fertilizers, growth of these crops in the US declined. For example, the state of [[Iowa]] led US oat production until 1989, but has largely switched to maize and soybeans.<ref name="Eller 2017">{{Cite news |last=Eller |first=Donnelle |date=5 October 2017 |title=Iowa has world's largest cereal plant, but state's farmers lack market for oats |url=https://www.desmoinesregister.com/story/money/agriculture/2017/10/05/iowa-has-worlds-largest-cereal-plant-but-states-farmers-lack-market-oats/690998001/ |access-date=23 January 2025 }}</ref>

<gallery mode=packed heights=160>
File:Havreskjering Fossheim Lindahl.jpeg|Harvest in [[Jølster]], Norway, {{circa}} 1890
File:Harvesting oats in Brastad.jpg|Harvesting oats in [[Brastad]], Sweden, 2021
</gallery>

=== Weeds, pests, and diseases ===

{{main|List of oat diseases}}

[[File:Puccinia coronata at Avena.jpg|thumb|Oat leaf infected with [[Puccinia coronata var. avenae|crown rust]] ]]

Oats can outcompete many weeds, as they grow thickly (with many leafy shoots) and vigorously, but are still subject to some [[broadleaf weed]]s. Control can be by herbicides, or by [[integrated pest management]] with measures such as sowing seed that is free of weeds.<ref>{{cite web |title=Oats: weeds and integrated weed management |url=https://www.agric.wa.gov.au/hay-production/oats-weeds-and-integrated-weed-management?nopaging=1 |publisher=Government of Western Australia |access-date=2 May 2024 }}</ref>

Oats are relatively free from diseases. Nonetheless, they suffer from some leaf diseases, such as stem rust ([[Puccinia graminis f. sp. avenae|''Puccinia graminis'' f. sp. ''avenae'']]) and crown rust ([[Puccinia coronata var. avenae|''P. coronata'' var. ''avenae'']]).<ref name="Pratap-2014">{{cite book |last1=Pratap |first1=Aditya |last2=Kumar |first2=Jitendra |title=Alien Gene Transfer in Crop Plants |year=2014 |location=New York City |publisher=[[Springer Science+Business Media]] |volume=2: Achievements and impacts |doi=10.1007/978-1-4614-9572-7 |isbn=978-1-4614-9571-0 |s2cid=26278759 |lccn=2013957869 |oclc=870451823 |page=51 }}</ref> 
Crown rust infection can greatly reduce photosynthesis and overall physiological activities of oat leaves, thereby reducing growth and crop yield.<ref>{{Cite journal |last1=Nazareno |first1=Eric S. |last2=Li |first2=Feng |last3=Smith |first3=Madeleine |last4=Park |first4=Robert F. |last5=Kianian |first5=Shahryar F. |last6=Figueroa |first6=Melania |date=May 2018 |title=''Puccinia coronata'' f. sp. ''avenae'': A threat to global oat production |journal=[[Molecular Plant Pathology]] |volume=19 |issue=5 |pages=1047–1060 |doi=10.1111/mpp.12608 |pmc=6638059 |pmid=28846186 }}</ref><ref>{{Cite web |url=http://www.ars.usda.gov/Main/docs.htm?docid=9919 |title=Oat crown rust |date=18 April 2008 |access-date=15 November 2015 |website=Cereal Disease Laboratory |publisher=[[United States Department of Agriculture]] Agricultural Research Service }}</ref>

=== Processing ===

[[File:Oatmeal.jpg|thumb|upright|Fully-processed [[porridge]] oats, ready to cook ]]

Harvested oats go through multiple stages of milling. The first stage is cleaning, to remove seeds of other plants, stones and any other extraneous materials. Next is dehulling to remove the indigestible bran, leaving the seed or "[[Groat (grain)|groat]]". Heating denatures [[enzyme]]s in the seed that would make it go sour or rancid; the grain is then dried to minimise the risk of spoilage by bacteria and fungi. There may follow numerous stages of cutting or grinding the grain, depending on which sort of product is required. For oatmeal (oat flour), the grain is ground to a specified fineness. For home use such as making [[porridge]], oats are often rolled flat to make them quicker to cook.<ref name="Decker-2014">{{cite journal |last1=Decker |first1=Eric A. |last2=Rose |first2=Devin J. |last3=Stewart |first3=Derek |title=Processing of oats and the impact of processing operations on nutrition and health benefits |journal=British Journal of Nutrition |volume=112 |issue=S2 |date=2014 |doi=10.1017/S000711451400227X |pages=S58–S64 |pmid=25267246 }}</ref>

Oat flour can be ground for small scale use by pulsing [[rolled oats]] or old-fashioned (not quick) oats in a [[food processor]] or spice mill.<ref name="Galvin-2011">{{cite book |last1=Galvin |first1=Meg |last2=Romine |first2=Stepfanie |title=The SparkPeople Cookbook |publisher=[[Hay House]] |publication-place=Carlsbad, California |date=2011 |isbn=978-1-4019-3132-2 |oclc=709682714 |page=98 }}</ref>