Malus fusca. The Pacific crabapple is found throughout the Pacific Northwest and is a beautiful small sized tree that bees and other pollinators love. It is well adapted to many soil types and of particular note can grow well on wet sites. In these places it can be used as rootstock or topworked to grow apples where common rootsocks would suffer. It produces small crabapples that are great forage for animals and birds and is also a good pollinator for many other apple varieties. Zone 5.