Quercus x warei Nadler - Oak

Quercus x warei 'Nadler' or Kindred Spirit is a remarkable hybrid oak tree known for its very columnar habit and exceptional robustness. This slender tree is appreciated for its tolerance to difficult conditions and its ornamental qualities, particularly its beautiful dark green leaves with a silver underside and its autumn colours. Suitable for medium to large gardens, it is perfect for structuring the space while adding a touch of elegance. This tree is hardy, resistant to wind and disease, and thrives in any deep, moist to dry soil.

Belonging to the Fagaceae family, Quercus x warei 'Kindred Spirit' is a cultivar obtained in 2005 by Earl Cully Nursery in Jacksonville, Illinois, USA. Resulting from the hybridisation between Quercus robur ‘Fastigiata’ and Q. bicolour, this oak combines the best characteristics of its parents. With rapid growth, it reaches a height of 10 to 15 m and a width of 3 to 5 m. Its branches are upright and form a very dense, narrow, and slender crown. Its young branches are brown-grey. The mature bark is composed of dark to light gray rectangular blocks. The leaves of the 'Kindred Spirit' oak, larger than those of Quercus robur, are ovate and lobed, a shiny dark green colour with a silver underside. They take on shades of brownish-yellow and bronze in autumn and remain on the branches for quite some time before falling off. The flowering, in May, takes the form of greenish-yellow catkins measuring 4.5 to 8 cm in length. Despite being a hybrid, this oak produces acorns. The 2 to 3 cm long acorns usually form in pairs, with one of the two often being underdeveloped. About half of the acorn is surrounded by a cupule covered with trigonous scales. The root system of this tree is deep and powerful, being both taproot and extensively spreading, ensuring a solid and long-lasting anchorage in deep soils.

The 'Kindred Spirit' hybrid oak is particularly resistant to diseases, including powdery mildew, and tolerates wind, drought once established and clayey and saline soils. It is hardy down to -28°C, allowing it to adapt to a wide range of climates and growing conditions.

The 'Kindred Spirit' oak can be used to form tall hedges and create green screens. It can also be planted in small groups or as a standalone specimen. It adapts perfectly to urban environments. It can be associated with Cornus mas (Cornelian cherry), Acer campestre (Field maple), Carpinus betulus (European hornbeam), and Prunus laurocerasus 'Greentorch' (Cherry laurel). At its base, a robust ground cover such as the variegated greater periwinkle Vinca major 'Variegata' can be planted. This oak also has the advantage of producing abundant leaf litter, which is beneficial for the growth of certain plants. And its fruits provide food for small animals like squirrels and jays.