Orido nishiki (Acer palmatum 'Orido nishiki' )

The leaves are variegated with pink and white and so is the bark of the new limbs and twigs. Zone 5. The plant is excellently captured in this photo by Michael Healy.

Oregon Sunset (Acer palmatum 'Oregon Sunset' )

Oregon Sunset forms a small rounded soft-looking tree with excellent leaf color from spring (sweet red) to fall (sharp red). You can see from Michael Healy’s photo that the leaves droop down and in providing that cuddly look.

Orange Dream (Acer palmatum 'Orange Dream' )

Think ‘Katsura’ only better; or at least that is the word on the street; the largest ones I have seen are in my two gallon smart pots so I haven’t seen what they look like as large trees or even out in the sun, but I have noticed that they are sturdier and more vigorous than Katsura which are good things. The leaves also seem to have more red in them than Katsura, but I will have to see the shining halo in the afternoon sun all summer and fall to say it is as good as Katsura. This photo is from Michael Healy.

Omurayama (Acer palmatum 'Omurayama' )

Omuryama is an upright but spreading and somewhat pendulous head. It gets fairly tall for a palmatum (maybe 20′) and almost as wide; the fall color is stupendous, a sort of glowing orange red.

Omato (Acer palmatum 'Omato' )

Omato has my favorite leaf shape: broadly ovate lobes on good sized leaves. The spring color orange tinged; the summer color is green and the fall color is various reds. The tree can reach 24′ but is in no hurry to do it.

Olsen's Frosted Strawberry (Acer palmatum 'Olsen's Frosted Strawberry' )

Olsen’s is my new favorite palmatum. It is a pink reticulate, slow growing and spreading.

Okushimo (Acer palmatum 'Okushimo' )

Like Kurui jishi, Okushimo has curled-in leaves, but the tree is much narrower and taller (which is not saying much in terms of height (10′)), and the leaves are a light fresh green in the summer. Fall color is variable, gold to red.

Okagami (Acer palmatum 'Okagami' )

Dark purple in the summer, Okagami turns scarlet in the fall. It is an upright growing tree to about 15′.

Ojishi (Acer palmatum 'Ojishi')

Ojishi is a dwarf Shishigashira.

Ogan sarasa (Acer palmatum 'Ogan sarasa' )

An unusual leaf color not captured by this photo, it is purple in the early spring and turns brick colored in the summer, quite nice, actually. The tree can get 30′. This one is probably 20 and isn’t getting much bigger. Fall color is orange red. zone 6