Tuesday, 19 September 2023

Planting Tulip Wood

 Planting Tulip Wood

The plantation was a P 1970s mature block of woodland.  I originally called it The Plantation but now call it the Tulip Wood. All my woods are technically plantations. It was mainly Rows of large sycamore separated by Rows of Red and Native Oak. Grey Alder had been planted on the wettest parts. The site is essentially flat but a central area is few inches lower. There is a stream along one side, into which the ditch between the Triangular and Rectangular fields feeds. The Sycamore were large trees and dominated. They all tended to be forked at 4-10 feet, otherwise they might have made timber.   Back in 2018 I had took down two pairs of rows, removing Grey Alder (Alnus incana), some etiolated native Oak and diseased Red Oak. The Red Oak had healthy canopies but several had small bleeds, two had small Ganoderma brackets and one with large Ganoderma brackets had blown down 2015. 

Images of the original line felling.

The rows of Sycamore were considered too big for me to bring down and do something with. Sycamore limbs that could be reached were removed. The first area was  planted with Douglas Fir, but drought meant I ended up beating up extensively with the Coast Redwood I had intended for the second pair of rows. Western Red Cedar and European Silver Fir were bought into the mix together with Monterey Pine from seed I had collected. 

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The felled timber was dragged to the edge of the track. There was more than I could sensibly burn. It was cut to lengths that would go in the car. The track is not made up in any way, and I have got stuck on in it twice. It is not worth trying to get the car down Oct to May. I did find a fire wood dealer with a lorry that had a grab who was prepared to take it away, and actually pay me! Over 2 years I did thin and underplant up about half the wood, with shade tolerate conifers. Drought sheep and deer did make the plantings a bit more varied than I had intended. 
As I was now able to sell the large wood over 4" and the lorry could get on to the wood  more trees could be removed and with some removed it became possible to remove the sycamore row  surrounded by new conifers. This left a larger area that was clear felled leaving a ring of mature trees around the edge. With a larger open area planting broadleaves became an option.  Pedunculate Oak, Tulip Tree and conifers mainly Coast Redwood were planted in approximately equal proportions 2020/21. Survival was good except for the Tulip trees at the North end these were replaced but failed in the drought of 2022.

The clear felled area planted Oct 2021. 
An attempt was made to make the area deer proof but deer did enter occasionally
browsing Oak and Douglas. 2023 recycled Tubex guards were put around the broad leaf trees, 120cm where the tree was nearly 120 or above and 75cm when not. Most of these trees that had not been browsed were 100 cm+ . Most of the Tulip Trees could self support but the oaks were very spindly. This did free up a lot of herbicide mesh guards and cut down guards for future planting.
Sept 2023. South side Tulip Wood
 everything growing well.
By the Autumn of 2023 the surviving Tulip trees were tall enough not to be browsed by deer. The Oaks which often got an extra half herbicide guard did suffer from some browsing. The Coast are susceptible to fraying and could do with tall tubes but they are too branched to do that easily. Though there has been steady bits of rain since mid June 23 the ground is too hard to get a cane in.
It is the weeds that have grown best.
Sept 2023 North side of Tulip Wood.
 Trees growing less well. 


There is a lot of coppice regrowth, Sycamore regeneration, Alder suckering and Elderberry. This needs removing over the winter and I will look at taking down some bits of the Sycamore. The shading is too great and the longer they are left the harder it will be and the greater the collateral damage. 


Picture on the left shows underplanted conifers between over towering Sycamores (Sept 2023). Many of the original Douglas fir suffered from browsing, drought and fraying. Those that were lost were replaced by Coast Redwood the first year. Those that were lost later are now gaps. Those that were planted outside the Sycamores are much larger, hence the hope to reduce some of the remaining Sycamores and Elder.

Monday, 11 September 2023

Norbury Park

Norbury Park.

On Friday 21st  July 2023 Small Woods members collected early in the overflow car park at the BIFoR FACE facility. We were welcomed by refreshments and good weather, before cramming into as few cars as possible for the drive to the Long Barn. A 1740’s threshing barn that has been renovated as a beautiful conference hall. We were each greeted with a copy of Jo Bradwell’s book “Norbury Park, An estate tackling climate change”. Jo Bradwell gave us a presentation of his approach to woodland management.
Professor Bradwell explained his non-agricultural background and how a desire to offset his “Carbon Guilt” had led to the acquisition of Norbury Park. Starting from a position of “I don’t know what to plant so I’ll plant everything”. His initial aim was to maximise carbon sequestration, in the established woods, newly planted woods and later on the arable land. The farm moved from arable to mixed grasses for silage and then to complex herbal lays. Increased production has long been shown for mixed pastures, particularly when nitrogen fixing legumes are included. The increased carbon in the soil accounted for half the over 5,000 tonnes net of CO2 sequestered by the estate in 2020 mainly by the farm soil.
In the woodlands he has developed a novel woodland management system. It is based on four principles. 1: Individual species are more productive in intimate mixtures, than in monocultures. 2: Greater leaf area in the maximum amount of light allows greatest growth. So, choose the trees you wish to favour early and remove the crowns of competing trees, hence Halo-Pollarding. Allowing the pollards to keep sequestering carbon. 3: As Nitrogen is often the limiting nutrient in biological systems, include nitrogen fixing trees in your mixtures.  4: Control pests particularly those that you can. Infection rates are reduced in intimate mixtures. Deer and squirrel numbers are kept as low as possible.
Non-anecdotal evidence for increased productivity in tree mixes is lacking in the U.K. but scientific papers were referenced showing it in natural and plantation stands abroad. There appear to be three main causes. Greater variety and depth of the canopy and understory enabling more light to be utilised. Greater variety in the depth that roots can extract water and minerals from, and possibly most significantly reduced pests and diseases. Though there is a wider range of pathogens and pests there is a wider range of predators and further between potential hosts. Species variety is considered key to reducing infection rates.
The presentation included examples of trees from the estate. A section of an 11 year old Hybrid Larch and 33 year old one of similar size from an estate monoculture were handed round. Powerful evidence for competition removal, but not necessarily for mixtures without knowing the thinning history of the monoculture. It is not known how the Forestry Commission had thinned the stand.
Professor Bradwell went on to explain the paucity of European species following the ice ages. Species failed to return across East-West aligned obstacles like the Mediterranean, the Pyrenees and the Alps. He advocated considering non-native species.
The presentation lasted about 35 minutes. There were many questions, several about carbon accounting. The major downside appears to be the complexity of the management and the extra labour required.
 
We then set off into the woods. The first stop was by an example of a squirrel trap that was being developed. It was table mounted and based on the lethal Kania spring bolt squirrel trap. The estate had believed vertically mounted bolt traps tended to have unacceptable bycatch rates.  The new trap was inclined to the horizontal, at 20 degrees. A feed hopper allowed corn bait to trickle out. There was also a trap door triggered after the bolt was sprung. This allowed any catch to fall to the floor and be scavenged, eliminating the necessity of daily inspection. The estate spends £16,000 a year on squirrel control, mainly because the 100 traps are inspected daily during the summer when trees are most at risk. It is hoped that after further trials and tweaks the trap will be made commercially available.
Our second stop was at the first of the mixed plantations from 2009. The diverse species range was immediately apparent. It lacked non-commercial conifers or nonnative broadleaves. Though the later were seen in later plantings. Examples of winners were obvious because of their girth and an orange band! Most of these were surrounded by trees that had been pollarded. Pollarding keeps the regrowth above deer foraging and allows carbon sequestration in the trunks and roots. It will be interesting to see the timber crop in 20 or 30 years. We did see an impressive Hybrid Larch. It was next to a Larch stump of nearly equal proportions, a slice of which was placed nearby and measured at 13” diameter. As a first planting it was very impressive and will have provided valuable lessons for the later plantings. There was plenty to inspire anyone thinking of woodland creation.
Driving back past bits of mature woodland and small patches of different planting dates, it was apparent non-native hardwoods were now being planted. Our tree ID skills were challenged. Then there was another chance to admire the Long Barn again over our lunches.
I have independently come to approach woodland management in much the same way as Prof Bradwell but think his case is not as strong as he tries to make it appear. 
 

The Wild Wood at Cairn Wood.

  The Wild Wood at Cairn Wood. When originally purchased the far end of Cairn wood was the area where the youngest willows were, they had al...