bringing food into the U.S.A.

xctraveler wrote:
Yeah, but, they don't grow citrus in Canada,

Sure they do, though often indoors and perhaps not commercially on any large scale. And homegrown fruits are a bigger threat to agriculture than the more heavily regulated commercial ones, as anyone who's ever seen a "do not transport home grown tree fruit" sign here in Washington State knows!

Here quoting from one Canadian nursery that sell treestock for fruit production:

Duncan's nursery, B.C. wrote:
Citrus - lemons, limes, mandarin oranges, blood oranges, navel oranges, kumquats, hardy citrus, kaffir limes- over 30 varieties - some of which are hardy enough to be grown outside;

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