Safe foods/drinks for Tree nut allergy sufferer

[Pedestriana]

I'm planning an event next year (quite early on) and I know one of the guests has a severe allergy to tree nuts.
Apart from the obvious things to avoid, should I be omitting anything else?
Likely to be a simple buffet with fruits and salads.

I can speak to the person in question, but would like to be some way towards having an inclusive menu when I do.

[AlmaMartyr]

I don't have much experience with allergies but bumping for you. I did a party last year with a nut allergy sufferer and loads of people on here were very helpful.

One easy thing was keeping all the wrapping so it could be checked. I bought a special nut free cake just for that guest too.

[Pedestriana]

Bumping again for some more ideas!