Croatian Chestnut

Thursday March 3rd in Sisak, Croatia

Thursday morning Stjepan and a colleague of his Boris Liovic arrived to pick me up right on time.  Boris is a plant pathologist, specializing in disease monitoring and management.  He proved to be an exceptionally appropriate companion for the day in that he has been studying the chestnut blight that is now affecting Croatian stands of sweet chestnut.  We’ll get into it later, but this is the same blight that decimated the American Chestnut nearly a century ago.

Feeling a bit rough from the previous night at the pub, I’d not gotten up in time to get any food.  I was therefore enamored when Boris asked if I’d eaten yet - and if not, if I’d like to try a local delicacy - burek.  I couldn’t have imagined more sweet-sounding words.  Boris, like Stjepan, spoke wonderful English and had a rosy glow reflecting from both his face and his spirit (turns out he just got back from a fishing trip to Africa - but I could imagine that Boris was a happy-go-lucky kind of guy even without the aid of a rejuvenating vacation).  

Before we reached our ‘burek’ destination, the two filled me in a bit on the climatic conditions of Croatia.  Possessing a broad range of climates from the Ionian coast in towards the eastern border, they are described as Mediterranean, Alpine, Continental and Pannonian.  Zagreb is about 2/3 of the way east of the coast and receives about 900 mm of rain annually (35.4”).  The eastern parts of the country receive something closer to 700 mm.  Their dry season generally starts in April and lasts much of the summer or for at least three or four months.  The distribution of their precipitation has been more erratic in the recent past and they’ve seen an increase in mean temperatures.  The soils in this part of the country are largely alluvial, and the area is bounded by three primary rivers - the Trava to the North, Danube to the East and the Sava to the south which forms their border with Bosnia.

Apparently, it wasn’t until 1780 that the nation saw significant exploitation of their virgin forests within the interior.  The coastal portions of the country were settled much earlier and were subsequently subject to more intensive forest management.  Nationally, forest extraction reached its peak between 1890 and 1920 during which time the total forest cover plummeted from 70% to 30%.  

Croatian forests have since come to receive a deep national appreciation, so much so, that they are deemed a ‘national treasure’ in their constitution.  In fact, it is illegal to export raw logs from the country - you have to add some value to it.  Recognizing the quality of the oak stands there, apparently some Italian forestry companies established mills within the country to harvest logs and do the minimal amount of processing necessary so that they might export the logs to their high-end furniture manufacturers in Italy, only for some of the wood to eventually return to Croatia in the form of kitchen cabinet built-ins, etc.

At this point, we were nearing our destination - the State Forest Office in the city of Sisak - where we were to meet with foresters Tihomir Pejnovic and Marko Sprisic.  In this region the primary forest species are the pedunculate oak, sweet chestnut and beech.  After an hour or two in the office, we’d planned a trip out to the field to look at some of the state managed coppice forests.  We arrived at the office and headed up to the second floor.  Our hosts greeted us warmly and we gathered in Tihomir’s office where we were soon brought coffee and grape juice.  Life felt pretty good at this point.  

While I’d come to suspect that this might be the case, my suspicions were soon confirmed - coppice is not viewed favorably by the state forest managers of today.  Concerned with developing management plans that generate income from their forest reserves, coppice products prove by and large to be economic losses for the state.  So much so that their most active management strategy with coppice woodlands has been to aim to convert them into high forest (what we think of as typical forest).  Unfortunately for them, this strategy has proven to be far more difficult than they’d like it to be.

At this point, I began to glean an even deeper insight into the context of coppice management today.  While I’ve recognized ever since first apprenticing in the sweet chestnut coppice of southern England that value-adding is absolutely key to developing an economically viable enterprise, I could see it even more clearly as I sat with these knowledgable, well-intentioned foresters who saw nothing but drawbacks to the coppice stands they inherited.  The black locust they have growing in their area is basically worthless to them.  They market sawlogs and veneer as their most valuable, primary products.  While fuelwood amounts to something, it amounts to little when compared to the returns they see from a mature, 100+ year old pedunculate oak forest.  Chestnut proves to be just about as useless - their primary outlet is the chemical industry where they reduce the polewood to pulp to extract the tannins for use in dyes, beauty products, etc.

As this realization began to crystallize within just a few short minutes of our interview’s start, I needed to find ways to keep them engaged while still gleaning useful information.  I could clearly tell that most of the questions I was looking to ask would be of little relevance to the management objectives of these men.  Though the insights I sought to glean would likely not be found in this conversation, I knew they still had much to offer.  What I came to learn was that their district is broken down into 25 management units, each of which has a management plan that’s reassessed and rewritten every 10 years.  Housed in a series of impressive volumes, each identified forest stand is routinely catalogued, with profiles that describe the location, species mix, stand productivity index, age since last harvest, total productivity, basal area per hectare, etc. - in other words, extensive data has been collected to describe the state of their forest resource.  And this is just the management plan - after completing the harvesting work on a site, the net results are tallied so that they can compare their prescriptions with the net result and better inform their re-interpretation of the plan come the next cycle.

What this means is that even for the coppice forests that they’re not all that keen about managing, they’ve got detailed yield data that will describe the total volume of wood produced on a range of sites with varying species mixes - information that will be invaluable to us in our research and very difficult to come by.  Fortunately, Stjepan has agreed to access some of this data and share it with us.

After an hour or so in the office, Boris, Marko, Stjepan and I set off for our field trip to an extensive stand of chestnut coppice (of which they possess 15,000 ha or 37,000 acres in this region) about 25 kilometers away.  On the way we discussed the current fuelwood market in Croatia and the relative values per unit volume.  In Europe they sell wood by the cubic meter (of which there are about 3.63 to the cord - our unit measure in the States - 128 cubic feet).  In this part of Croatia, green (unseasoned) fuelwood goes for between $35-40 per cubic meter - really not that much cheaper than prices in many parts of the States.  This wood is usually delivered cut in 1 meter lengths and is then up to the buyer to reduce to lengths of either 1/2 or 1/3 meter.  Marko said that the average house in that area will burn between 7-20 cubic meters of wood per year.  Most of the houses are poorly insulated brick structures, so they are very ineffective at preventing heat loss.  This wide range varies depending on a number of factors, including relative insulation as well as heater type.

After 20 minutes on the road, we climbed up a mountainside on a forest road where we stopped to examine a few stands of sweet chestnut.  Here the effects of the blight were painfully visible with 30% or more of all the stump sprouts infected with canker-like wounds rendering the polewood useless for most building or craft work.  Believed to have been imported to Europe from the States (where it was originally imported from Asia) in the early 1950s, the blight has done considerable damage to stands across the continent though this was by far the worst I’d see to date.  Interestingly, it didn’t have the same devastating impact that it had on trees in eastern North America and the reasons for this aren’t exactly clear.  Perhaps it has something to do with the Mediterranean species’ relative tolerance.  It’s really unclear.  But what we saw is that the blight tends not to affect sprouts until they reach about 5 or 6 years of age, and then they get hit hard.  It was most definitely a sad site to see.

But beyond the blight, the chestnut coppice here really looked to be a stand that represented little value to its owners.  They did continue to manage it as coppice - the challenge and costs of actively shifting it towards a high forest structure, coupled with the effects of the blight, represent a far greater investment than the state is willing to make.  But the stands featured stools that appeared to receive little conscious care, inefficient spacing and just generally the type of attention you might expect to see from a site managed on a large scale - actually a 12-15 hectare stand that would be managed by a contiguous clearcut all at once.

I did take some measurements here - 

The first cant featured stools that were about 7-8 years of age.  The average diameter at breast height ranged from 3-3.7” or so and the stand possessed about 90 square feet of basal area per acre.

At the second site, of the same age, there were about 5-6 stems per stool and 100 square feet of basal area per acre.  Average diameter at breast height ranged from 2.8 to 3.6” and the poles were about 32’ high.  The spacing in this areas seemed to average about 10-12’ on center.

We explored the woods for another half an hour or so and returned to the State Forest Office where we were treated to an enormous lunch, complete with wine and crepes.  We enjoyed good laughs and a considerable joke-exchange before saying goodbyes and parting ways.  

When we arrived back in Zagreb, Boris invited us over to his home where he wanted to show us some of the furniture he’d designed and had built.  He also took the opportunity to share about 5 different types of schnapps that he’d procured from friends and/or infused with various herbs.  After a half hour of sampling, I was about ready to call it a day.  Stjepan dropped me back off at the hostel soon thereafter.  

It had been a very informative day.  Though I didn’t really end up making the connections I’d necessarily intended to, I felt that I’d gained an absolutely valuable insight into the true context of coppice management in Croatia in this day and age.  In many ways, I find that engaging with your critics can be far more valuable than surrounding yourself with supporters.  In the long run, I know that this experience will help to sharpen my focus and be more clear about the intentions I bring as I work to develop economically viable, consciously-designed coppice systems.