This is the view from the top of the track down to the larger building on the quinta. In many ways it encapsulates the nature of the “Green Heart of Portugal” – forested mountain ranges cut deep by meandering river valleys, peppered with tiny white villages perched on mountain ridges, surrounded by land terraced and richly cultivated with olives, vines, fruit trees, vegetables … Idyllic.

But it encapsulates something else about the Green Heart of Portugal too – an ecological disaster-in-the-making presently taking hold in Portugal’s forests. The tree on the left is dying.

Pinewood nematode, pine wilt nematode, pine wilt, pine wilt disease … all names given to the disease affecting rapidly growing numbers of the Maritime pines (Pinus pinaster) which form the vast bulk of Portugal’s forests. It’s caused by the nematode Bursaphelenchus xylophilus, a tiny worm that infests the sap wood of various species of pine, and is vectored through various wood-boring insects, depending on where it’s present. Native to North America Japan and Asia (see comments below), it has spread to the USA, Australia and Portugal, presumably via imported timber.

Not only does the nematode kill the trees it infects, it also renders the timber unusable. If left standing for more than a few months, the wood of the now-dead tree undergoes a change in structure and turns into a strange spongy substance that, aside from being useless for building, clogs the chainsaw blades that try to fell it and barely even burns, generating almost no heat.

When I first came here just 3 years ago, there was scarcely any evidence of it. People were talking about it appearing around Arganil, 20km away, but there was no obvious evidence of it in this valley. Now, this is the view across the valley.

The photo at the beginning of this post was taken last year, when we removed 3 trees with the disease on the quinta. This year we are going to have to take out more – I’ve counted around 10 and that’s before a thorough exploration of our bit of pine forest. Next year there will probably be more still …

So we’re bringing forward our plans for the woods and stepping things up a gear. The aim is to try and spot the infected trees at the first sign of infection and fell them before the wood becomes useless for firewood, burning them as soon as they’re dry, and stockpiling healthier trees for future years’ firewood, making clearings where we can start to plant more hardwoods. In doing so, we hope to steal a march on the disease. Lowering density and increasing diversity may offer some protection to remaining healthy trees, but even if it doesn’t, by the time the disease decimates the surrounding forest, we will hopefully have a well-established start to a new, more diverse and healthy forest.

My hopes are that it can also turn out to be a successful example of an alternative approach to the disease. Rather than clear-felling and replanting with eucalypts (now against the law, but flouted with virtual impunity see comments below) which will cause even more environmental damage and increase fire risk, I hope to show that it’s possible to regenerate a largely indigenous but also productive, valuable, non-flammable forest from which high-value timber such as chestnut can be harvested regularly through coppicing and provide a good return in less time than it would have taken to bring pine forest to maturity and harvest. Although we won’t be harvesting our trees in this way, for local people it’s part of their livelihood and how they look on their forest. If they’re to turn away from present practices, then there needs to be a reason and viable incentive to do so.

We’ve watched others in the valley and around spraying frantically and it doesn’t seem to have made any difference. Their crops are infected just the same. And inevitably, after more Smith and Beaumont periods in a month than you could shake a stick at, not to mention a downpour that gave the lush canopy a centre parting, I finally discovered potato blight (Phytophthora infestans).

The only thing to do in this instance was to cut the haulms before the blight had a chance to find its way into the tubers, even though there was no sign of imminent flowering.

After doing so, I dug down into a corner of the potato bin to see what we’d managed to grow from one plant. It was quite some depth before I encountered the first tuber. I had to dig down to the level of the lowest 2 planks. Good news from the point of view of the blight reaching the tubers. Bad news from the angle of proving the theory behind the vertical cultivation of potatoes.

This is what I harvested from this one plant. The potatoes are good, but there are few signs of any inclination to produce offshoots any higher up the stems than the first 20cm or so. If this is typical of the rest of the crop, then there are some questions to be answered. Is the lack of tuber-producing offshoots down to the premature harvest? The variety we grew? The environmental conditions which brought the potatoes on so fast? Other factors which I haven’t considered? Any combination of the above?

Reading up on potato blight, I was immediately struck by the fact that blight is not a problem affecting wild varieties of potato. It struck me because I’d made the same observation concerning the grapes on the quinta. All the cultivated vines are showing signs of black rot (Guignardia bidwellii), another fungal disease that thrives in warm humid conditions, but in cases where the vines have reverted to a wilder state in uncontrolled growth from the roots, there is no sign of disease and the growing fruit is abundant and healthy.

Perhaps this is the lesson here? Rather than fight the processes of natural selection, we should simply adapt our tastes to the healthier, wilder varieties?

I spoke too soon.

We purchased this alternator from Presto Wind in the USA on the basis of its advertised power curves and a couple of videos showing no evidence of cogging, which was the problem with the first generator we tried. As soon as it was installed, it was running well over its claimed threshold for generating usable power, so it was just a matter of waiting for the bearings and rotors to run in and then the batteries would be getting some much-needed juice 24/7. Or so we thought …

After emails going back and forth for well over a month now, we (that’s me and my neighbours, who are installing a wheel on their part of the stream, and Wayne, the systems’ engineer) have a decidedly unpleasant taste in our mouths from our dealings with Presto Wind.

Our M-24 units are not producing anything approaching their advertised power curve. To begin with, when we had more water volume (it hasn’t rained in well over a month), they were producing about 50% of what they should be. Now it’s not even 30%. They’re not even producing enough power to contribute to the batteries and because of the particular way the company have responded and dealt with this, I’m taking the step of writing about our experience in some detail so others can read and judge for themselves.

At first we thought we must have got something wrong, but checking and rechecking the wiring found no errors and all connections were tight. I reported the low output to Presto Wind. The company asked was I sure the tachometer I was using to measure the rpm was accurate, but if we weren’t getting the expected output then something may be wrong. So far so good. I then, over the course of many emails, supplied full details of my system (and relevant details of my neighbours’) with photographs of all wiring plus regular updates on the rpm of the units and the power they were generating, making clear on every occasion that this was being measured open circuit with no load, which is the same conditions under which they produce their power curves. And we weren’t using a tachometer. We were counting wheel revolutions over a timed minute and multiplying that by the gear ratio, so we knew the rpm of the M-24s (+/-5% depending on whether you calculated the ratio by gear wheel diameter or number of teeth).

I frequently had to hassle them into responding after supplying them with information and getting no reply, whereupon I would be asked questions I’d already answered. After repeating myself several times and resending photographs, I was beginning to wonder if they’d paid attention to anything I’d sent, but still didn’t think more of it than that.

Eventually the company responded by saying there was nothing more they could do to help, claiming the underperformance could all be explained by water flow, wheel size, and other system components which, together with 35% efficiency, would easily explain our results. It wasn’t their PMA. It was physics. The units were installed and we couldn’t return them. I pointed out, as I had several times already, that not only was the water flow data irrelevant since we knew the rpm of the PMA (which they were obviously aware of, having asked about our means of measuring it), the rest of the system was completely irrelevant too. We were measuring the power open circuit straight off the rectifiers. And while 35% efficiency might be relevant to wind power, it was not appropriate for hydro. 60% is more the norm.

To prove beyond doubt that it was nothing to do with the rest of the system, we disconnected it all from the rectifiers, measured the power at the rectifiers in exactly the same manner as their demonstration videos (and of course got the same readings we’d been getting all along), took photos of it all, and sent that off with a request that they respond within a week. No response.

I emailed again, saying we wanted to return the units under warranty for a full refund because they were not performing as advertised. This time their explanation for the units’ underperformance was that we must have ‘damaged’ them, despite the units being installed by a qualified engineer in exact accordance with their instructions and with them having seen photographs of the installation and being able to identify no error.

During the course of the exchange, I asked them at least 3 times to confirm the basis of the relationship between rpm and power output in their permanent magnet alternators, because to do this would focus the discussion on the precise nature of the problem and clarify whether there was a fault in the units or whether they were making false claims for their performance. They ducked the question every time. When I sent an email asking just this question, they answered a different question.

We are still trying to get our money back, but it looks very much as if we’ve been had.

Since this has happened, we’ve heard reports of other people using these units in wind applications and finding the same underperformance, including units that have been re-badged for another company. And there’s posts on forums (here and here) suggesting that the company’s advertised power curves are intentionally deceptive.

So we’re back to looking for the right generator again. Intensely frustrating, particularly since Wayne hasn’t had to use a generator all winter with his wheel. Even though it’s now producing only 100W with the river being so low, his batteries are still full every morning. Unfortunately the PMG on his installation is no longer in production. Wayne is beginning to think about building one himself …

(The bottle of Portuguese cava was very good though. That I can recommend.)

Today I bought a reel of hosepipe. I knew I had a large funnel somewhere, and a ball of twine. With 15 minutes’ work with the ball of twine, an hour clearing vegetation from the top of the waterfall, a ladder, and a bungy strap, we now have a working irrigation system for the main vegetable bed on the yurt terrace. A bit Heath Robinson, but considerably more efficient than the watering can.

(Ah yes. The knee support. Another injury. This one a result of a well-aimed strike by heel of teenage daughter in teenage strop who’d just been made to laugh. Much against her will, of course. The support bandage is helping with cruciate ligament damage …)

Our lettuces have been struggling to develop. It’s a bit too hot now and they’re getting so fried during the day it’s stunting their growth. Before putting in the effort to dig a whole new bed for them in a shadier location (not good for damaged knees), I reckoned it was worth trying a local solution to the summer sun: shading by bracken. The fronds pull up very easily and with a snip of the secateurs, their stems can be shaped into straight points which push into the soil. Bracken gets such a bad press, it’s nice to find a good use for it.

A quick trip to Arganil medical centre (and with huge thanks to Rick & Sarah) and 10 stitches later, I looked like something out of a Tom & Jerry cartoon.

Waiting to be stitched up at Arganil. The sign behind me says “não espere!” — “don’t wait!”

The stitches came out last Wednesday and the dressings this Monday, two weeks to the day I did it. It’s healing very well, but has somewhat curtailed my abilities to get on with stuff. Frustrating, but Helen and Oonagh have been stars. Thanks also are due to the staff at Coja medical centre for the redressing that was required 3 times a week.

Lesson? Do not wield axes while brain is out of gear. Don’t think I’ll be forgetting that one in a hurry …