augered or conveyed into a bin for storage. Sometimes, when there is not enough bin space, they are augered into portable grain rings, or piled on the ground. Oats can be safely stored at 12-14% moisture; at higher moisture levels, they must be aerated or dried. Yield and quality In the United States, No.1 oats weigh ; No. 2 oats must weigh . No.3 oats must weigh at least . If , they are graded as No.4, and oats under are graded as "light weight". In Canada, No.1 oats weigh ; No.2 oats must weigh ; No.3 oats must weigh at least and if oats are lighter than they do not make No.4 oats and have no grade. Oats are bought and sold and yields on the basis of a bushel equal to or ) in the United States, and a bushel equal to or ) in Canada. "Bright oats" were sold on the basis of a bushel equal to or ) in the United States. Yields range from on marginal land, to on high-producing land. The average production is , or . Straw yields are variable, ranging from , mainly due to available nutrients and the variety used (some are short-strawed, meant specifically for straight combining). Genome Avena sativa is an allohexaploid species with three ancestral genomes (2n = 6x = 42; AACCDD). As a result, the genome is large (12.6 Gb, 1C-value = 12.85) and complex. Cultivated hexaploid oat has a unique mosaic chromosome architecture that is the result of numerous translocations between the three subgenomes. These translocations may cause breeding barriers and incompatibilities when crossing varieties with different chromosomal architecture. Hence, oat breeding and the crossing of desired traits has been hampered by the lack of a reference genome assembly. In May 2022, a fully annotated reference genome sequence of Avena sativa was reported. The AA subgenome is presumed to be derived from A. longiglumis and the CCDD from the tetraploid A. insularis. Genetics and breeding Species within Avena can hybridize and genes introgressed from other "A" genome species has contributed with many valuable traits, like oat crown rust (Puccinia coronata f. sp. avenae) resistance. is one such trait, introgressed from A. sterilis CAV 1979, conferring all stage resistance (ASR) against Pca. It is also possible to do introgression of traits in oats from very wide intergeneric hybridization. In contrast to wheat, oats sometimes retain chromosomes from