Quercus robur 'Argenteo Marginata' - Variegated English Oak
Family - Fagaceae
Size - The species will average 40 to 60 feet under normal landscape conditions. I would suppose that the variegated form will be slightly smaller, probably 35 to 50 feet with a comparable spread. Seems to have a medium growth rate. Expect about 1 1/2 to 2 feet per year under good cultural conditions.
Foliage - I have heard varying opinions on the variegated form. Most have been "nothing to get too excited about". 'Argenteo Marginata' has very attractive variegation. The foliage is a deep blue-green with portions of the margin being a pure white. Light greens blend in to portions of the interior of the leaf. It could be there are various variegated forms around thus accounting for the differences of opinion.
Flower/Fruit/Seed - Acorn. 1997 is it's first year to set nuts. Begins to bear after 5 to 6 years.
Bark - Dark gray and smooth in youth, probably like the species in maturity, grayish black and furrowed.
Pests and Diseases - None noticed. Mildew which is often a problem on the species and the variety Fastigiata, has occured slightly on 'Argenteo Marginata', but it's not anything that seems to be overly serious.
Landscape Use - Could be used in the average home landscape since I believe the variegated form will be somewhat smaller. Can still become a good sized tree in time. The variegation is fine enough to be attractive without being gaudy or obtrusive in the surrounding landscape. From a distance it appears to give the tree a mottled appearance.
Performance - 8 The tree on campus is only about 5 years old. It was acquired in late 1992 as a graft, approximately 12 inches in size. It was container grown, and planted in the Fall of 96. It grew approximately 2 1/2 feet per year while in a container. It currently in July of 97 is about 10 to 12 feet in height. It prefers a moist, well drained soil, is pH tolerant, sun to part shade. The variegated foliage is unaffected by full sun, scorching or sunburn is not a problem. It would appear that this tree would be suitable for use in to zone 8. The species is hardy to zone 4.