Pests & Disease
Insects of concern include armyworms, bulb mites, click beetles, cutworms, leafminers, leek moths, nematodes, onion maggots, and thrips.
The onion family is vulnerable to a number of diseases from leaf blight, fusarium basal rot, and purple blotch to black mold, slippery skin, and smudge.
Many of these maladies are not among the most common threats to bunched onions, though green onions are susceptible to common diseases such as bacterial soft rot, bulb rot, damping off, downy mildew, grey mold, onion yellow dwarf virus, rust, smut, Southern blight, twister, white tip, and wilt.
Storage & Packaging
Recommended storage temperature is 32°F with high humidity (95 to 100%) to maintain moisture, color, and overall quality. Green onions are sensitive to ethylene and should be separated from producers; additionally, they can emit their own odor, which can be harmful to the flavor of other fruits and vegetables such as apples, corn, grapes, mushrooms, and rhubarb.
References: North Carolina State Extension, Oregon State University, U.S. Food & Drug Administration/University of California, Davis Western Institute for Food Safety & Security.
GRADES & GOOD ARRIVAL
There are two grades for green (bunched) onions, U.S. No. 1 and U.S. No. 2. For U.S. No. 1, product should be fairly well-formed, firm, tender, clean, free from decay, and free from damage caused by seed stems, roots, foreign material, disease, insects, and injury.
Bulbs should be well trimmed and tops fresh, green, unbroken, and free of bruising. Bunches should have uniform clipped tops. Overall length should be from 8 to 24 inches and diameter from one-quarter to 1 full inch.
For U.S. No. 2 green onions, product should not be badly misshapen, fairly firm, tender, clean, free from decay and from serious damage.
Bulbs shall be fairly well trimmed, green, and free from serious damage. Length shall be not less than 8 inches and diameter not less than one-quarter inch or more than
Generally speaking, the percentage of defects shown on a timely government inspection certificate should not exceed the percentage of allowable defects, provided: (1) transportation conditions were normal; (2) the USDA or CFIA inspection was timely; and (3) the entire lot was inspected.
|U.S. Grade Standards||Days Since Shipment||% of Defects Allowed||Optimum Transit Temp. (°F)|
There are no good arrival guidelines for this commodity specific to Canada; U.S. guidelines apply to shipments unless otherwise agreed by contract.
References: DRC, PACA, USDA.