zfs problems after rebuilding system

[tech-lists]

Hi,

Importing two zpools after a hd crash, the first pool I imported
auto-loads at boot. But the second one I'm always having to zfs mount
(zpool name) then mount the zfs subdirs. The system was like this:

ada0 (this had the OS on. It was replaced after it crashed. Not a member
of any zpool, not zfs at all, no root-on-zfs). New
freebsd-11-stable-snapshot was installed to this disk.

ada1 \
ada2  -- these made up zpool0, a raidz pool. Each device is a 1TB disk.
ada3 /

zpool1 - this is striped, one 4TB disk, attached via usb3

zpool1/c - this is compressed with lz4
zpool1/important - this has copies=2 enabled

I ran zpool import zpool0 and then zpool import zpool1 and both imported
without error. However despite setting the mountpoint for zpool1 as
/zpool1, on reboot I always have to:

# zfs mount zpool1

or I won't see the drive in df -h or mount or zfs mount.

But I *will* find it at its mountpoint /zpool1. If I do a ls -lah on
that, I can see zpool1/c and zpool1/important as dirs but not in zfs
mount or (normal) mount, nor can I see the other dirs that are not vdevs.

If I then zfs mount zpool1 I can see all the dirs and vdevs on that disk
off its root, in ls -lah. But I dont see the vdevs in zfs mount. I have
to zfs mount zpool1/c and zfs mount zpool1/important to see the vdevs in
zfs mount.

Confusingly, I didn't need to and don't have to do any of that for
zpool0. What am I doing wrong/what am I missing? Why is zpool0
automatically loading but zpool1 is not? Before ada0 (the failed disk)
was replaced, both loaded on boot.

thanks,
-- 
J.