Centre field
The period from September 2024 to March 2025 has signalled a much drier period then the previous year. This has enabled the team at Carbon Plantations to carry out significant maintenance and winter processes across our 458 hectare plantations. It has also allowed us to consider alternative timing on planting trees of differing maturities. We are also tracking improving underlying soil conditions and a more bio-diverse canvas.
We ended the 2024 growing season with trees at an average height of 4.5 metres at Euston Estate (Carbon Plantations). Some, that had been technically cut after year one, were up at 6.5 metres. We remain on track to have a half-harvest at Euston in 2027/28.
Root Formation
In September, we carried out a radar analysis of the depth of the roots at Honington on the Euston Estate. Those with a 20mm thickness or above were down to 1 to 1.5 metres below the surface and had run along the irrigation lines to a length of 1 metre. We noted that neighbour root systems were not directly competing in their source for nutrients. We also noted that the organic matter, and natural nitrogen availability within the soil ecosystem was on the rise from its baseline readings. More on this later.
Survey area of the tree radar operation, Wireless station, November 2024
Survey area of the tree radar operation, Wireless station, November 2024
The rooting of the trees seen within the chart below is significantly higher than that which would be seen in the same aged native tree species, with the radar only picking up the larger roots over 20mm in diameter or dense clusters of tree roots. Indeed, it is likely that many of the very shallow detections are dense mats of roots, which together have sufficient biological mass to be detected as a single root.
Tree root morphology side on view, Wireless Station
Weather Patterns – 2024/25
We are growing Paulownia in a changing world with changing weather patterns; however, we are happy that our soils, on our plantations, are now becoming more resilient and more healthy. The soils are becoming increasingly able to cope with rainfall variability. The soils are settled and are absorbing rainfall and increasingly having the ability to hold on to it and turning rainfall in to effective rainfall.
Since inception, we have not seen soil, and therefore nutrients, lost from the plantations even with the heaviest periods of rain. This is encouraging as much of the soil contains nutrient, such as phosphate that will cause eutrophication of rivers and lakes. This is the enrichment of water, causing algal blooms, reducing oxygen and increasing silting of watercourses.
Whilst difficult to predict, we are led to believe the rainfall increasingly comes as ‘events’ so periods of rainfall are heavier and last longer. For every 1°C temperature increase an increased level of 7% of rainfall occurs. Atmospheric temperature increases represent energy and this triggers water molecules keeping a higher percentage of water vapour maintaining higher levels of rainfall. This is then deposited in higher amounts, often in concentrated weather events.
If we look at the rainfall for example during the winter months (October to March) and compare the previous two years at Euston Estate we have the following readings:
2023-2024 – 305.4 mm rainfall
2024-2025 – 212 mm rainfall
This is not the whole story, the intensity of the rainfall as mentioned is probably more important. It is clear that 2023-24 the intensity of rainfall in October and February gave rise to waterlogging in low lying areas and the unduly wet February reduced the amount of time we were able to undertake preparatory work. 2025 is completely different to date. We have adapted our processes to cope with these changing conditions, which have included remedial drainage work and more timely interventions so as to avoid compacting or damaging the soils.
Far less rain in 2024-25!
We are not alone, all Agriculture is having to change its methods and try to create more resilient soils. At a micro level, we appear to have speeded this up with our plantations, as the maturing trees, and their root systems, are holding more moisture underground.
Soil Improvement at our Plantations
Of course, we are increasing the carbon removed from the atmosphere and the tree appears to be very efficient in this respect but we are also improving soils and the stability is leading to some exciting comparisons.
We have recently undertaken detailed soil analysis to understand the level of mineral nitrogen available for the coming seasons and it is encouraging to note that we have an additional 20 kilos/ha of available nitrogen more than corresponding arable cropped fields.
It is clear that we have increased the soil life or organic matter since we have planted Paulownia and throughout a season, the nutrient is released more naturally for the growing trees. We have recently reported 88 kg/ha of nitrogen availability in the soil, which should be compared with an arable field that will average 60 kg/ha this year from similar soils. This development is likely to improve further over time.
Reaching for the sky
Middle Austins, Euston Estate, September 2024