Enligt Kanada Border Services Agency :
Many different kinds of items can introduce foreign threats into Canada. These include things as diverse as:
- Food, such as raw or cooked meats, fruit/vegetables, milk;
- Homemade articles, such as items made from plants or wood;
- Houseplants;
- Live animals, including pets;
- Firewood;
- Plant cuttings, seeds; and
- Muddy hiking boots.
...
Be sure to clean all soil and organic debris off of any items including hiking boots, vehicles, boats and gardening and construction tools/equipment.
De kan kasta bort dem om det finns tillräckligt med lera på dem för att få agenten att vara orolig. För att vara säker, tvätta dina skor innan du packar dem.