'had', being the Simple Past tense, indicates 'a fact' - a person either has one, or doesn't/I had one or I didn't have one.
'used to have' introduces the idea of 'having for a period of time'.
So - I had a bad fall from that horse.
I used to have a Ford Whizzer, but I traded it in on a Mazda Whazoo.
(Indicates ownership for a period of time.)
I used to have trouble with my swing, until I took some lessons with Tiger Woods.
used to have bad headaches - had them over a period of time before, say, a new drug got rid of them for me
I had a headache. (A one-off and took an aspirin).
In your sentence, you are referring to the fact that one day they were there, the next blown down - so: 'had'
BUT: if you were feeling nostalgic and felt like you had lost trees that you had grown up with and loved (kind of thing!), then 'used to have'
In your sentence, it depends on the speaker's point of view. Is he a hard-nose realist, or a softy at heart?
(The words people choose to express their view of the world can be very revealing about their nature and mentality, and they often don't realize it!)