Pine vs Fynbos

November 1, 2012

Neels de Ronde tackles the controversy raging over the recent call to remove plantations from the Western Cape by suggesting that there is room for fynbos AND pine...

pine vs fynbos
Burnt fynbos one year after a wildfire near Still Bay.

Forestry consultant Neels de Ronde responds to the controversial article by Dr Brian van Wilgen and Professor Dave Richardson, published in the June issue of SA Forestry magazine, that expresses the view that it does not make economic or environmental sense to pursue forestry in the Western Cape.

With this writing (expressing my personal opinion in the light of the recent discussions about this topic and sharp differences of opinion) I would like to review the issue from different perspectives. I would like to approach this by means of discussing the problems experienced in both plantation forestry and fynbos conservation areas and explore whether the situation around this critical interface can be improved in the Cape regions. Seen in a  different way, I am of the opinion that both disciplines can work together in finding solutions.

Is forestry 'bad news' for fynbos?
I think there has been some general misunderstanding about the invader problem in fynbos which needs to be clarified first. There are a number of exotic invaders threatening fynbos of which 'pine tree stands' is only one. Eucalyptus gum trees and Acacia mearnsii (black wattle) plantings in plantation-form have been attempted in the Cape regions at a small scale, but it was soon discovered that these threatened to become serious invaders in fynbos, and subsequently further plantings were stopped. Hakea is also still a problem invader in some districts (such as on the drier slopes of the Outeniquas and Tsitsikamma Mountains), although some success was achieved with biological control.

A more serious mistake was made by introducing certain exotic Acacia species to stabilise sand dune (driftsand) areas (species such as Paul Jackson and Rooikrans), which soon invaded large fynbos areas on the plateau between the mountains and the ocean basin, particularly along the coast where 'drifting sand' was a problem in the past. Some terrible Acacia jungles have developed in the process as a result of this action (see picture), which have taken over thousands of hectares on natural fynbos land completely. The authorities responsible for eradicating this weed have basically 'given up on this problem' and, as a result, wildfires are increasing in these districts at an alarming rate, in both size of burned-over area and fire intensity.

Next on the list is Acacia longifolia, which is choking some of the most important river systems in the Western Cape winter rainfall region (in my eyes far more damaging with regard to restricting water supply to the Cape Town metropole than pine plantations!). Then there are other species as well, but these are probably presenting lesser threats to fynbos.

To see the fynbos invader problem in perspective, I have to mention that invaders per se are not the only problems facing the ecologists and conservationists in attempting to reach a sustainable maintenance of biodiversity-level in this unique plant kingdom. Neither is forestry the only industry at which a finger can be pointed. There is, for example, agricultural land, where the plough has wiped out more than 90% of the drier renosterveld and large areas of coastal fynbos. Industrial, urban and rural developments are also claiming an increased proportion of fynbos and farmers have turned thousands of hectares of fynbos into seasonal crops, such as wheat lands, leaving very little fynbos for conservation.

Farmers adjoining catchment areas are also burning fynbos far too regularly at damaging short rotations whenever they can, causing significant changes in species structure and survival, in particular, the drier, northerly slopes of the most prominent mountain ranges in the Cape regions. To top it all, nature conservation organisations are fighting a continuous battle to finance their labour and retain experienced managers, causing (indirectly) serious fire management problems, which are creating more and more extreme wildfire situations as a result of a lack of prescribed burning application. ALL these factors combined are threatening the maintenance of biodiversity and the future existence of fynbos. A number of disciplines can be held responsible for this, of which forestry (in my eyes) is only a minor contributor to the invader and other problems identified.

The fynbos invader problem
Has the invader problem been properly quantified? I do not think so. Mention has been made of 'forestry plantations affecting water flow' but figures provided come from a few long-term hydrological studies at a few selected sites, results from which can only be extrapolated to a few very restricted areas. Most of these experiments were concluded decades ago, when, for example, the extent of the Acacia longifolia problem was not as serious as it is today, which is a far more serious threat to the maintenance of sustainable water supplies to the Cape metropole.

As pine is one of the invaders considered to be a threat to fynbos, let us look at this problem from another angle. Pinus pinaster was (particularly during early forestry days) the main cause of invader spread in the region, particularly along plantation-fynbos interface lines. These invasions were mainly experienced in the foothills of the main Western Cape mountain ranges, but this was mainly where poorly growing races and strains of the species were established (such as those from the 'Esterelle' and 'Landes' strains and, in particular, from the so-called 'Franschhoek' strain). These (mostly experimental) plantings were soon phased out completely, and in the process, even the 'Portuguese strain' of the species, showing the best tree growth characteristics of all Pinaster Pine races and strains, was phased-out. Today, there is very little of the species left in plantation form.

Mostly clean and Pine-free
However, agreed – the invader damage was already done in some adjoining catchments – and in my opinion, these fynbos-invaded sites are where almost all recent Pine invaders come from (thus from originally-invaded sites) and NOT from the existing plantations. This, I observed to be the case in most plantations I recently visited: The plantation-fynbos interfaces are mostly clean and Pine-free. However, where clear off-site plantings were attempted (such as, for example, near Caledon and Riviersonderend during the 1960s, as assisted by government foresters in these cases), the spread of P. pinaster was particularly bad in these areas for decades. Now this appears to be mostly restricted to the southerly aspects. I am the first to agree that no acceptable quantitative research has been carried out in this case to date either, so we are restricted to our own observations over time to come to some general conclusions.

Looking from a different angle at the size of the industrial plantations (planted area), the Tsitsikamma is probably the most profitable of the Cape regions. With generally good tree growth rates recorded, the invader problem is also not as serious there as elsewhere, particularly now that P. pinaster stands have almost all been converted to other species, such as P. elliottii. The Southern Cape region has a mix of different Pine species planted, with some contrasting tree performance results. Where some very poor P. pinaster off-site plantings are found, Pine invaders can still present problems. However, such stands were also mostly converted to species other than P. pinaster, and others were written off. Although the fern Gleichenia polypodioides (an indigenous fern) has taken over many poor sites with a metres-high mat resisting any invader regeneration, some southern slopes of the Outeniquas have been invaded by Pine species, in particular, with P. pinaster. The latter infestation is mainly restricted to some specific sites.

The western section of the Western Cape Province (winter rainfall region) only has a minor area under Pine plantation, which has now been reduced to something below 20 000 ha, even considering that some 'exit' areas have now been 'reversed'. The remaining plantations are mainly situated on better sites with no new invader problem to speak of. If we only consider the fynbos interface areas, what are we talking about in terms of 'problem areas' compared to the area of the whole region? Less than 1%? Is this worth fighting for, to see this eliminated? Forestry has by now learned to keep invaders out of adjoining fynbos. Is it not time to have both plantations and fynbos (shrubland) exist hand in hand, as is being done effectively in so many other countries?

Fighting invaders in fynbos
First of all, I think there is a desperate need (i) to quantify the existing invader spread situation by main invader species, and (ii) to determine to what extent spreading has increased over say the past ten years. Then we have the problem quantified in terms of percentage spread, also over time. Such a study does not have to cost a fortune, and by using existing technology (clear satellite images, remote sensing technology and others) the end result can be accurate, even considering the fact that many fires have most probably occurred during any ten-year period.

A need to work systematically
Secondly, the authorities fighting the invader problem should get their house in order, by working systematically according to a programme as set out by our specialists, at a rate that has been calculated by them. At present, they don't come close to making a dent in the existing invaded areas and when 'exit' areas are added, they do not even treat those areas properly, oftentimes creating worse regeneration from invaders than before the 'exit' plantation stands were removed. We should not even think about phasing out industrial plantations completely because these are very low on my priority list as explained earlier, unless there is some significant change in effectiveness of present weed control measures.

Thirdly, forestry must be working according to a dedicated programme to ensure no further Pine infestation takes place. This is a level the foresters have already reached, but they will have to maintain and improve their efforts as and where required. Our fynbos conservationists and ecologists should be consulted on a regular basis with regard to progress in this direction, so they can concentrate on more serious invader problems elsewhere. Foresters should indeed assist them in eradicating any invading Pines on property under their control, in cooperation with conservationists and in particular, mountain catchment managers. Together, we can succeed!

Published in August 2012

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