Blog written by Wilfred Mole, director of Pertwood Organic Farm

Lower Pertwood Organic Farm has been in the ownership of the present custodians for 15 years but before that it was fully organic for over 20 years. 

The previous owner Mark Houghton-Brown, who inherited the farm from his grandfather, was passionate about the concept of organic farming and laid the groundwork for the current landscape.

Since acquiring the main organic farm, two additional adjacent farms have been acquired which are currently still conventional. The plan is to convert them to organic when current government policy initiatives with regards to rewarding farmers for improving soil health is fully clarified. In the meantime, they provide us with a very useful way of constantly comparing a field that has been organic for 35 years to one that is constantly under pressure from man-made destructive inputs.

We have, more recently, employed specialists to carry out studies to examine the ecology of this landscape.

Photo of a bee

Bees abound and return to natural hives that are never disturbed.

One focus has been a comparison of ground beetle and spider populations between organic farmland, which has been completely free of chemical fertilisers and pesticides, and the harsher commercial farming environment that exists on many farms today.  We employed a professional entomologist, Stuart Corbett, to carry out intensive surveys on fields in both categories, and he produced a report clearly indicating significant differences between them. 

This report is available on our website, but a brief summary of his findings showed that Carabid beetle populations were three and a half times and spider populations were twice as numerous in a field growing organic oats than in a conventional field of winter wheat.  

It was surmised that, as well as the absence of direct chemical toxicity, soil conditions in the organic system benefited survival of these invertebrates.

Enhanced levels of soil organic matter increase its moisture retaining capacity and this enables more successful development of prey for both beetles and spiders. These moist conditions also increase larval survival of beetles that are more prone to desiccation in drier conventionally farmed soils. In addition, greater weed coverage present on organic fields provides more shade, thereby increasing soil moisture retention.

Importantly, as well as these measured effects on biodiversity, this study also highlights the potentially adverse consequences to agroecosystems of conventional farming practice in forecasted climate change scenarios and indicates that organic farming can help to combat its impacts.

Photo of ground beetles collected during a survey

Numbers of Carabid beetles recorded on organic and conventional land

Other studies on the farm, such as large-scale monitoring of bird populations, have also emphasised the positive results of organic farming.

Despite the fact all these surveys were carried out, there is a “strange and intangible feeling” about farmland that is left to develop naturally. We plant organic crops and inevitably we have learned to tolerate the plants that accompany these crops. We have developed skills over the years to ensure that our crops are able to compete sufficiently to produce a viable end result.

We have noticed, particularly in the last twelve months, that a significant “Covid era” vibrancy has developed on the farm and even the casual observer cannot miss the fact that plant diversity is increasing. Specialists who understand the history of the chalk downlands and who know what plants used to grow there, are astonished at the emergence of plants they seldom came across but are beginning to re-appear.

Photo of a butterfly

Gatekeeper butterfly taking flight from Hawkbit in Big Down. This small yellow-flowered plant resembles a small dandelion and is often used to indicate old meadows Seen between June and October. If flourishes in fertile soils and sunshine.

Obviously, in order for this to happen there has to be a management initiative which respects the landscape and limits the amount of intervention. Livestock can play a very important role and if the correct animals are placed in the correct fields at the right time of the year, it actively promotes the emergence of rare species.

A recent initiative is our “Old English” wildflower meadow, Poppy Knapp, now in its fifth year of a seven year developmental programme. We have followed the correct methodology to the letter. The field is left in peace except for two interventions;

At the end of summer, when all of the plants have shed their seeds, we will remove the hay in order to give the broad diversity of plants more access to light. However, by putting sheep into this field in October, which is mandatory, the seed on the surface is worked into the soil by hooves while the sheep add a fertility component as well. This is a good example of where we need to leave landscapes well alone where possible, but occasionally intervene in order to provide the input that nature would have provided seasonally.

Photo of pollen rich plants in a field

50 acres of quiet areas and field margins are planted to pollen rich flowering plants annually.

In the distant past herds of grazing, wild animals would have maintained some areas as open grassland thwarting an inevitable development of scrub and then woodland. In more recent history, man replaced the wild animals with his livestock, potentially engendering the development of our chalk downlands. In order to retain this almost unique and certainly exquisite landform, we have to continue traditional management with, mainly sheep, or it will only feature in the dusty pages of future history books (or, perhaps, rusty web pages!). 

Sheep on Big Down at Lower Pertwood farm

We are also concerned about the philosophy of landscape tidiness which prevails in many quarters. Many people believe that the elimination of plants that are not of immediate use and the “tidying up” of land is the secret to success. There might be some short term rewards but the longer-term effects are reducing the health of our soils, polluting rivers and slowly but surely causing serious unseen damage.

Our philosophy is encapsulated by the complete and utter removal of the worst of modern, commercial, industrial type agriculture from the landscape. It is interesting to note that the organisers of the Glastonbury Festival are going to great lengths to stop people urinating randomly on the landscape because they have proved scientifically that what people ingest, particularly if they take drugs (medicinal and otherwise), is extremely harmful to the creatures that live in the nearby rivers. Heavy rainfall can leach substances from the landscape into the rivers, which of course are nature’s drainage systems. Unfortunately, a tiny percentage of the chemicals that people put through their systems can be sufficient to kill off rare life forms that are attempting to survive in these rivers. 

Perhaps the biggest tragedy is the average person may be completely unaware of what is happening, and for many farmers it is also largely irrelevant. However, there does appear to be a growing perception of the ability that nature has to rebalance ecology in a positive way, enabling biodiversity to fulfil its roles. Nature must, however, be allowed to do this.

We have significant butterfly populations on the farm, many of them reliant on plants regarded as totally unacceptable within the context of conventional farming. An intensive and progressive educational programme to increase awareness is vital if we are to avoid the catastrophic culmination of current policies.

At a local, and sometimes even a national level, we are encouraged by the significant increase in interest in what we do, how we look after the soils and the biodiversity reliant upon it. Our regular newsletter Pertwood_Autumn_Newsletter_2021.pdf  provides very clear evidence that by working with individuals who understand the needs of certain specific categories of life forms, whether it be owls, bees, butterflies or rare downland plants, we can open a door to allow all of these important categories an opportunity to return and thrive.

Nature is waiting for the invitation.

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