Besides his work at WUR and the Von Gimborn Arboretum, Leo Goudzwaard is also active at the 'Climate Forest inspiration' arboretum in Wageningen.

Arboretum Oostereng is not officially a LIFE Climate Forest demo site, but the arboretum's demo route offers plenty of inspiration for forest managers and owners who want to work on climate-smart forest management. In this special piece of forest in Wageningen (11 ha.), everyone is welcome to see with their own eyes how some 600 different species of trees and shrubs 'do it' on poor sandy soils.

From LIFE Climate Forest, we visited Arboretum Oostereng in Wageningen on 21 November 2024. As early as 1911, the famous garden architect Leonard Springer established at this location an Arboretum with special trees from all over the world. After World War II, the Forestry Commission (project partner within LIFE Climate Forest) bought the land and again planted a number of special trees. Then the whole area was left alone for a long time.

There are several Caucasian silver firs in the arboretum, from still quite young (photo above) to older, considerably tall specimens (photo below).

Leo Goudzwaard is currently chairman of the foundation and he coordinates the work of the 30 active volunteers who maintain the arboretum, lay paths and plant new species. There are now more than 600 different shrubs and tree species in the arboretum. There are old specimens from the time the original arboretum was laid out (over 100 years ago) and recently planted young trees.

"Arboretum Oostereng aims to preserve or restore as much as possible the old trees, the ideas of the former owners, the design of garden architect Springer and the former learning function for students and the public. We are also committed to preserving special trees and groups of trees and making them visible again. And that certainly includes trees that are interesting for climate-smart forest management."

"For example, we have two Abies test gardens here with about six silver fir species, including the Greek silver fir, which is now found almost nowhere else. Those silver fir species are interesting in view of climate change. You see a lot of Norway spruce dying right now due to drought. This has been going on since 2018, and across Europe this involves thousands of hectares. Now you can see here in the arboretum that those silver firs on dry sandy soils do thrive in the longer dry periods we have had in recent years. They are probably sufficiently drought-resistant to keep up with climate change. Similarly, we have several abies nordmanniana - or Caucasian silver fir - and they cope wonderfully well with drought. With the younger specimens, you can see the needles nicely up close and with the larger specimens you can really see the potency."

This tree hazel is also in the demo route.

"Besides the silver firs, we have more species in the arboretum that are interesting in the context of climate change. Both conifers and deciduous trees, some of which have been there longer or, on the contrary, have been planted quite recently. On our site there is a complete list of species that can be seen here and I am also working on a 'demo route alternative tree species'. Around February 2025, that route will be ready and then forest managers and other visitors working on climate-smart forest management will be able to take a very focused tour of the tree species present that will be of interest then."

"I think it is important to show alternative tree species, because many tree species are dying in the Netherlands now. The alternative tree species are there not only to replace, but also to bring more variety to Dutch forests. This, of course, also in the context of risk spreading. After all, I also notice the consequences of climate change myself in the forest. A number of species are really declining. More trees die, their vitality declines, they become smaller... you can see it happening. Larch trees and Norway spruce in particular are suffering now."

This sweet chestnut in the arboretum is a selection tree, 30 metres tall, dead straight and selected to have offspring from.

"Besides silver fir, there are more good alternatives. For instance, the tree hazel is very interesting. We have the tallest one here in the Netherlands and you already see the tree hazel in more places in ordinary forests. The field maple is also a nice alternative, as are the coast redwood and the sweet chestnut. You see all those species here."

"Alderberry is also a good example. It copes well with drought and provides rich litter, which in turn is good for the soil. Alderberry is already fairly well known to forest managers, but we also have species that are somewhat less well known. There are also a number of elm species that hardly anyone knows about, but that do well. Consider the Japanese elm, for example. It does well, but does not grow very large on sandy soils. You can experience that here and then it can be a conscious choice to include the species."

Several elm species - such as this cherry bark elm (Ulmus villosa) - are also doing well.

"It is also just what a forest manager is looking for. For example, a nice species for fill wood is the forest willow. That's one of my personal favourites. It is not an interesting species for timber production, but if you are looking for a species that is valuable in the context of biodiversity and enriching the soil... then again the forest willow is very interesting. And sometimes you have to experience a species for yourself. One of our goals is to create a broad collection to show professionals and the public what is available. As a visitor, you can see many different species together and get all kinds of ideas for your own forest, street or park. With the demo route, we can also show within a single tour that there are still plenty of tree species that are climate-resistant and can do well on our high, dry sandy soils."

Curious about this 'Climate Forest-proof' route? Around February, the demo route will be on the Arboretum Oostereng site and there will, of course, also be a direct link on the LIFE Climate Forest site.