GERMANY: A new addition to its Volvo fleet will boost productivity at this renowned tree and plant nursery
by Nigel Griffiths
Expectations are high among staff at the Hamburg-based tree and plant specialists Lorenz von Ehren Nurseries as they await the arrival of a new L120 wheel loader to join their fleet of Volvo machines. The new machine will transform and accelerate the process of transplanting the many large, mature trees cultivated by the company, including 40-year-old oaks.
The L120 will be fitted with a four-tonne, 2,000mm hydraulic tree spade, a customized attachment capable of extracting the root balls of giant trees from the soil in minutes, while keeping them intact.
Lorenz von Ehren is one of Europe’s largest tree and plant nurseries and, founded in 1865, the oldest. Established by Johannes von Ehren, the son of a Hamburg sea captain, it remains a family-run company, now in the hands of managing director Bernhard von Ehren, the fifth generation.
“Today, we have more than 500,000 trees and shrubs under cultivation across 550 hectares of fertile soil in three locations,” he explains. “Giant oaks are among the spectacular mature species we ship to many European countries.”
With 1.5 million of the nursery’s trees and plants delivered to destinations across Europe every year, thousands of its plants are on the road every day. The most challenging are the mature trees such as the oaks.
In 1904, Lorenz von Ehren, son of Johannes and the second generation to go into the family business, succeeded in hauling a 40-year-old weeping beech over a distance of 9km – an enormous effort at that time. Skip forward 110 years to October 2014, when a huge oak tree from the nursery was shipped to London as part of the transformation of Kings Cross station. The 63-year-old oak (Quercus Palustris, or pin oak) was 12m high and was sent to England by sea on a ferry.
That tree is now the focal point of the 27-hectare green site in one of London’s most vibrant districts. In 2013, the nursery delivered 37 pin oaks to a country estate near Manchester in the UK. The company can boast client references from Switzerland to Russia.
“There are only a few nurseries able to provide such fully-grown trees,” says von Ehren. “We are known throughout Europe, and landscape architects and even individuals come from far afield to inspect our trees and choose what they want.”
Trees and plants require considerable time and space to grow. Around 170 nursery staff are involved in the cultivation of sites in Hamburg, Bad Zwischenahn and Rellingen. Among the avenues of trees and parkland are specimens that have reached the grand old age of 100 years.
During the growth cycle, the trees are generally transplanted every four or five years. This is an occasion to trim the root ball. The traditional approach to digging up giant trees at the nursery requires the use of two machines. An EW160D wheeled excavator has the job of digging around the base of the tree to free the root ball. A Volvo L90C wheel loader then takes over to lift both tree and root ball out of the ground using a standard fork attachment. The tree is then carefully secured and lowered on to the back of a truck for transport.
This process currently takes up to one hour but will be totally transformed by the arrival of the new L120. Equipped with the giant hydraulic tree spade, the Volvo machine will lift the tree and root ball clear of the ground in less than five minutes.
The company has been working with Volvo equipment for many years and its fleet is currently made up of eight wheel loaders – models L35B, L60F, L70D and L90C – and the highly mobile EW160D wheeled excavator.
The new tree spade has four blades, capable of effortlessly extracting a 2m-wide root ball from a depth of 126cm.
Now standard equipment across the plant nursery industry, the concept of the tree spade attachment was initially developed by a specialist tree-spade designer in Nuremberg in collaboration with Lorenz von Ehren Nurseries.
The Volvo L120 is being customized with a joystick specially designed for manipulating the four tonne spade.
“The joystick is an innovation we have helped design,” says production manager Kay Hackmack. “It controls each of the four blades of the spade individually while steering the wheel loader,” he explains. “The spade is also equipped with a camera inside the blades to give the operator extra visibility and precision.”
The nursery has been working for some time with a smaller version of the system for handling the younger trees which need regular replanting. A 1,400mm spade attachment is fixed to a Volvo L60F wheel loader and helps free each tree from the ground in a matter of minutes. In this way, up to 100 young trees can be replanted in just one day.
In future, the nursery’s much larger older trees will enjoy a similar level of productivity. “We will be able to prepare trees must faster using the L120 and the time saved will be very valuable,” says von Ehren.
“The oak trees being uprooted now were planted by my father and the ones we are planting now will be harvested by my children 20 years from now,” he explains, adding: “How do we know what conditions they will have to face in 20 years time?” For the answer, von Ehren has turned to modern science.
“We have been supporting science and research projects for many decades and urban trees are currently the focus of attention. We know that in 20 years’ time we will have to provide trees which are resistant to heat, frost and climatic fluctuations.”
In September 2015, the nursery celebrated its 150th anniversary by organizing the Lorenz von Ehren ‘Green Pioneers’ Symposium together with the European Garden Awards.
“While technology, environment and fashions have changed, our basic motivation has remained the same: we love trees,” affirms von Ehren.
The nursery’s meticulous approach to cultivation has seen it awarded the highest ‘Ökoprofit’ (Ecoprofit) certificates by Germany’s Regional Plants Certification Association for environmental programmes.
In November 2015, the nursery won the prestigious TASPO Award, presented by the industry news weekly for the green market, as ‘Nursery of the Year 2015’, to add to its collection of prizes and honors.