Rhus

Like it or loathe it, there are few plants which rival it's stunning display of colours in early Autumn. It is a deciduous shrub or tree which grows up to about 8m high. and comes into it's own in late summer and autumn when the tall velvet covered 'drupes' (flowers) appear and slightly later, the leaves turn from green to all shades of yellow orange and red.

Drupes: Rhus typhinia

History  
 
Originally from China and Japan, Rhus was brought to England in the 1690's from the Americas where it was used both to create a lemonade style drink from it's crushed fruit and to exact a tanning agent from it's bark. Native Americans used both berries and leaves combined and incorporated into traditional smoking mixtures.

Synthetic plastics have been only developed in recent times, but the Chinese were using resin from Rhus verniciflua to create waterproof and durable coatings since around 1000BC. The Rhus was used up to the 1950's when synthetic plastics became easier to make, cheaper and able to be mass produced on a large scale. 

Rhus: Autumn leaves

A number of varieties are these days planted for use as ornamental species only these days: Rhus aromatica, Rhus microphylla and Rhus trilobata.


Propagation

Propagation is generally by seed although the suckers which sprout periodically from it's root system can be carefully removed and potted on to transplant elsewhere. 

Cultivation

Trees need to be planted in full sun. They are generally tolerant of clay, sand, loam, alkaline, acidic, occasionally wet and well-drained soil. They are also tolerant of drought conditions.


Care

The tree generally will need little or no annual pruning, however, controlling it's suckering roots can be very difficult. Roots have been known to grow under 3m deep foundations and spring up on the other side. Mowing the shoots off is not recommended as they end up as sharp stumps and recover anyway.

Furry stems which give an indication of the 'Stag's Horn' origin.

That said, if you want a really good display of foliage and are prepared to miss out on the flowers and fruit, the stems maybe cut back to a stubby framework of branches or nearer to the ground mid spring time. Trees which have been left can be brought back to their former selves. This can be done either by cutting back around a third of the oldest stems each year of a three year period until all the tree has been rejuvinated or by cutting all the stems back to near ground level if you are feeling braver!


Pests and Diseases

Aphids do suck the plants sap but are not generally a problem. Rhus do not generally suffer from specific diseases but can suffer from fungi which causes cankers, Leaf spot and Powdery mildew. Verticillium wilt is perhaps the most dangerous for the tree, causing branches to wilt followed by the death of it's foliage. Prune out any infected branches.

The tree's sap is caustic and as such is a severe skin irritant. Gloves should always be worn when pruning the tree. It is not a good idea to burn the branches or foliage as the smoke is said to be toxic.

A small number of trees can be seem at their best in early October at:

Sizergh Castle & Garden
Sizergh
Near Kendal
Cumbria
LA8 8AE

Telephone: 015395 60951
Web site: Sizergh Castle: National Trust